Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| purification and characterization of a proteolytic active fragment of dna topoisomerase i from the brine shrimp artemia franciscana (crustacea anostraca). | the atp-independent type i topoisomerase from the crustacean artemia franciscana was purified to near-homogeneity. its activity was measured by an assay that uses the formation of an enzyme-cleaved dna complex in the presence of the specific inhibitor camptothecin. the purification procedure is reported. purified topoisomerase is a single-subunit enzyme with a molecular mass of 63 kda. immunoblot performed on the different steps of purification shows that the purified 63 kda peptide is a proteol ... | 1992 | 1311554 |
| comparison of messenger rna pools in active and dormant artemia franciscana embryos: evidence for translational control. | in response to environmental anoxia, embryos of the brine shrimp artemia franciscana enter a dormant state during which energy metabolism and development are arrested. the intracellular acidification that correlates with this transition into anaerobic dormancy has been linked to the inhibition of protein synthesis in quiescent embryos. in this study, we have addressed the level of control at which a mechanism mediated by intracellular ph might operate to arrest protein synthesis. two independent ... | 1992 | 1349912 |
| nucleotide variation and molecular structure of the heterochromatic repetitive alui dna in the brine shrimp artemia franciscana. | it has been suggested that dna bending could play a role in the regulation of gene expression, chromosome segregation, specific recombination and/or dna packaging. we have previously demonstrated that an alui dna family of repeats is the major component of constitutive heterochromatin in the brine shrimp a. franciscana. by the analysis of cloned oligomeric (monomer to hexamer) heterochromatic fragments we verified that the repetitive alui dna shows a stable curvature that determines a solenoidal ... | 1992 | 1474602 |
| aerobic heat shock activates trehalose synthesis in embryos of artemia franciscana. | encysted embryos (cysts) of the brine shrimp, artemia franciscana, contain large amounts of trehalose which they use as a major substrate for energy metabolism and biosynthesis for development under aerobic conditions at 25 degrees c. when cysts are placed at 42 degrees c (heat shock) these pathways stop, and the cysts re-synthesize the trehalose that was utilized during the previous incubation at 25 degrees c. glycogen and glycerol, produced from trehalose at 25 degrees c, appear to be substrat ... | 1992 | 1592115 |
| cloning of a cdna encoding an artemia franciscana na/k atpase alpha-subunit. | clones of cdna that code for an isoform of the artemia franciscana na/k atpase alpha subunit (naka alpha) have been isolated. the sequence of the longest of these clones (paratna136) is 3595 nucleotides; it codes for a 1004-amino acid protein whose sequence is identical to that of two previously sequenced artemia naka alpha peptides. the encoded protein is over 73% identical to drosophila melanogaster and vertebrate naka alpha s, and 73.8% identical to another artemia naka alpha isoform previous ... | 1991 | 1657719 |
| liquid chromatographic determination of efficacy of incorporation of trimethoprim and sulfamethoxazole in brine shrimp (artemia spp.) used for prophylactic chemotherapy of fish. | the brine shrimp artemia, an excellent live food source in aquaculture, has been studied as a carrier to deliver selected chemotherapeutic agents to fish for prophylactic treatment of infectious diseases. to monitor the efficiency of incorporation of trimethoprim and sulfamethoxazole in artemia franciscana, a sensitive and specific analytical method was developed. it is based on homogenization of artemia nauplii in methanol, extraction of lipids with hexane, solid-phase cleanup on c18 cartridges ... | 1991 | 1810182 |
| highly repetitive dna sequence in parthenogenetic artemia. | the study of the structural organization of the eukaryotic genome is one of the most important tools for disclosing the evolutionary relationships between species. artemia (crustacea, phyllopoda) offers a very interesting model for speciation studies. the genus, distributed all over the world, comprises both bisexual sibling species and parthenogenetic populations, exhibiting different chromosome numbers (diploidy, polyploidy, and heteroploidy). digestion of genomic dna of the parthenogenetic ar ... | 1991 | 1901366 |
| arrest of cytochrome-c oxidase synthesis coordinated with catabolic arrest in dormant artemia embryos. | we have examined cytochrome-c oxidase (cox) biosynthesis in brine shrimp (artemia franciscana) embryos during preemergence development (ped), as well as its inhibition under anaerobic dormancy, to determine whether transitions in intracellular ph (phi) have a regulatory influence on anabolic processes. under control aerobic conditions (embryo phi greater than or equal to 7.9), incorporation of radiolabeled amino acids shows that substantial biosynthesis of cox occurs during 12 h of ped (500% inc ... | 1990 | 2159729 |
| a binding protein (p82 protein) recognizes specifically the curved heterochromatic dna in artemia franciscana. | dna bending has been suggested to play a role in the regulation of gene expression, initiation of dna replication, site specific recombination and dna packaging. in artemia franciscana (phillopoda anostraca) cells we have revealed that an alui dna family of repeats, 113-bp in length, is the major component of the constitutive heterochromatin found in the species. by analysis of cloned oligomeric (monomer to hexamer) heterochromatic fragments and electrophoretic experiments we verified that the r ... | 1990 | 2258053 |
| heat dissipation during long-term anoxia in artemia franciscana embryos: identification and fate of metabolic fuels. | microcalorimetric measurements of brine shrimp embryos during 6 days of anoxia indicated that heat dissipation was rapidly suppressed to 2.7% of control (aerobic) values over the first 9 h. energy flow continued to decline slowly to 31 microw.g dry mass-1 (0.4% of control) during the subsequent 5.5 days. within 2 h after returning anoxic embryos to aerobic conditions, heat dissipation rose to 77% of control rates. the calorimetric/respirometric (cr) ratio across this 2-h recovery period increase ... | 1990 | 2292613 |
| sequence-directed curvature of repetitive alui dna in constitutive heterochromatin of artemia franciscana. | an alu i family of repeated dna sequence 113 bp in length was found to be the major component of the heterochromatin in artemia franciscana. on the basis of the analysis of cloned oligomeric (monomer to examer) heterchromatic fragments we predicted that the sequence could produce a stable curvature in chromosomal dna. this prediction was confirmed by polyacrylamide gel electrophoresis analysis and by electron microscope observations. the anomalous mobility of these fragments is reversed when the ... | 1989 | 2813062 |
| tissue-specific alternative promoters regulate the expression of the two sarco/endoplasmic reticulum ca-atpase isoforms from artemia franciscana. | the sarco/endoplasmic reticulum ca-atpase gene from artemia franciscana is transcribed into two mrnas of 4.5 and 5.2 kb that code for protein isoforms differing at their carboxyl terminus. northern blot assays and anchored polymerase chain reaction (pcr) experiments have shown that these two mrnas also differ at the initial part of their 5' untranslated region. the 5.2-kb mrna-specific 5' untranslated region is present as an independent exon whose transcription is regulated by a promoter differe ... | 1995 | 7546295 |
| nuclear-cytoplasmic translocations of protein p26 during aerobic-anoxic transitions in embryos of artemia franciscana. | embryos of the crustacean artemia franciscana survive continuous anoxia for periods of years, during which their metabolism comes to a reversible stand-still. a question of some interest concerns the maintenance of cellular integrity in the absence of biosynthesis and an ongoing energy metabolism. the present paper continues previous work on an abundant protein (p26) that undergoes extensive intracellular translocation during aerobic-anoxic transitions, exhibits several characteristics of stress ... | 1995 | 7628526 |
| hox genes and the diversification of insect and crustacean body plans. | crustaceans and insects share a common origin of segmentation, but the specialization of trunk segments appears to have arisen independently in insects and various crustacean subgroups. such macroevolutionary changes in body architecture may be investigated by comparative studies of conserved genetic markers. the hox genes are well suited for this purpose, as they determine positional identity along the body axis in a wide range of animals. here we examine the expression of four hox genes in the ... | 1995 | 7630416 |
| ontogeny of cardiac function in the brine shrimp artemia franciscana kellogg 1906 (branchiopoda: anostraca). | in newly hatched brine shrimp (artemia franciscana) cardiac organogenesis and function could only take place with the onset of segmentation. consequently differences in age, body size and temperature (in the range 22-34 degrees c) affected the ontogeny of cardiac activity only indirectly, through their influence on developmental stage. once present the frequency of cardiac activity (heart beat) increased with increasing body size and concomitant differentiation of cardiac tissue. at least initia ... | 1994 | 7798869 |
| gene expression after resumption of development of artemia franciscana cryptobiotic embryos. | the steady-state levels of six different mrnas have been studied during artemia franciscana development. some of these mrnas are present in the cryptobiotic cyst, like those coding for cytoplasmic actins, sarcoplasmic/endoplasmic reticulum ca(2+)-atpase, and the na+, k(+)-atpase alpha-subunit isoform coded by the clone paratna136. the expression of these mrnas is markedly induced during cyst development. a small increase in mrna levels can be observed for some genes at very early stages of devel ... | 2010 | 7818853 |
| structure and expression of a polyubiquitin gene from the crustacean artemia. | we have characterized two polyubiquitin genes from the crustacean artemia franciscana. one of them, ubi1, has nine ubiquitin units and an intron of a minimum size of 3.5 kb that ends 7 bp before the initiator atg. the 5' end of the transcript from this gene has been identified by anchored pcr. the existence of the other gene (ubi2) was inferred from several cdna clones that differ from ubi1 in the c-terminal extension and in the 3' untranslated region as well as in the nucleotide sequence of the ... | 1994 | 7841785 |
| in situ hybridization analyses of na, k-atpase alpha-subunit expression during early larval development of artemia franciscana. | the spatial pattern of expression of the mrna encoded by the na,k-atpase alpha-subunit cdna clone paratna136 was determined by in situ hybridization of first, second, and third instar artemia franciscana larvae. this mrna was expressed at high levels in the salt gland, the antennal gland, and the end of the midgut, which are the three main osmoregulatory organs in artemia at these stages of development. the pattern of expression was similar at the three stages of development analyzed, although t ... | 1995 | 7897181 |
| genomic organization and developmental pattern of expression of the engrailed gene from the brine shrimp artemia. | we report the isolation and characterization of an engrailed gene in the crustacean artemia franciscana. the artemia gene spans a genomic region of 15 kilobases and the coding sequence is interrupted by two introns. it appears to be the only gene of the engrailed family present in the artemia genome. the predicted engrailed-like protein is 349 amino acids long and contains several domains including the homeodomain, well conserved when compared to other proteins of the engrailed family. based on ... | 1993 | 7903633 |
| acute blockage of the ubiquitin-mediated proteolytic pathway during invertebrate quiescence. | many organisms withstand adverse environmental conditions by entering a reversible state of quiescence that may last for months or years. in this report we provide evidence that the reduction in adenylate energy status and the associated intracellular acidosis occurring during anoxia-induced quiescence combine to inhibit, directly or indirectly, the initial step in the ubiquitin-mediated proteolytic pathway in embryos of the brine shrimp artemia franciscana. the levels of ubiquitin-conjugated pr ... | 1994 | 7943430 |
| identification of an artemia franciscana retropseudogene containing part of the last exons of the sarco/endoplasmic reticulum ca-atpase-encoding serca gene. | a genomic clone has been isolated which contains sequences highly homologous to part of exon 14 and exons 15, 16 and 17 of the artemia franciscana sarco-endoplasmic reticulum ca-atpase(serca)-encoding gene, but none of the introns. the homologous region extends to the 3' end of the mrna, although the poly(a) tail is not present. the structure of this clone suggests that it represents a 5'-end-truncated retropseudogene (r psi). | 1994 | 7959022 |
| the complete mitochondrial dna sequence of the crustacean artemia franciscana. | the complete mitochondrial dna (mtdna) sequence of the brine shrimp artemia franciscana has been determined. it extends the present knowledge of mitochondrial genomes to the crustacean class and supplies molecular markers for future comparative studies in this large branch of the arthropod phylum. artemia mtdna is 15,822 nucleotides long, and when compared with its drosophila counterpart, it shows very few gene rearrangements, merely affecting two trnas placed 3' downstream of the nd 2 gene. in ... | 1994 | 7966370 |
| global arrest of translation during invertebrate quiescence. | comparing the translational capacities of cell-free systems from aerobically developing embryos of the brine shrimp artemia franciscana vs. quiescent embryos has revealed a global arrest of protein synthesis. incorporation rates of [3h]leucine by lysates from 4-h anoxic embryos were 8% of those from aerobic (control) embryos, when assayed at the respective ph values measured for each treatment in vivo. exposure of embryos to 4 h of aerobic acidosis (elevated co2 in the presence of oxygen) suppre ... | 1994 | 8078909 |
| speciation in the artemia genus: mitochondrial dna analysis of bisexual and parthenogenetic brine shrimps. | from the cloned mitochondrial dnas (mtdnas) isolated from two bisexual species, one mediterranean, artemia salina, and one american, artemia franciscana, and two parthenogenetic (diploid and tetraploid) strains of artemia parthenogenetica collected in spain, physical maps have been constructed and compared. they are extremely different among themselves, much more than the differences between drosophila melanogaster and d. yakuba and in the same range of different mammalian species such as mouse/ ... | 1994 | 8169960 |
| extensive intracellular translocations of a major protein accompany anoxia in embryos of artemia franciscana. | cells of encysted gastrula embryos of the crustacean artemia franciscana exhibit extraordinary stability during prolonged anoxia. we find that they contain an abundant protein (referred to as "26-kda protein") that undergoes translocation to the nucleus during anoxia. the reverse translocation rapidly occurs when anoxic embryos are returned to aerobic conditions. a similar translocation appears to take place in embryos exposed to 42 degrees c aerobic heat shock and prolonged exposure to low temp ... | 1994 | 8174644 |
| structure of artemia franciscana sarco/endoplasmic reticulum ca-atpase gene. | genomic clones coding for the artemia franciscana sarco(endo)plasmic reticulum ca-atpase have been isolated. the restriction map of the overlapping clones covers a region of 65 kilobases of dna. nucleotide sequence of mrna coding regions shows that the gene is divided into 18 exons separated by 17 introns. compared with the structure of the rabbit sarco(endo)plasmic reticulum ca-atpase 1 gene, 12 of the introns are in the same position, 8 introns present in the rabbit gene are absent from a. fra ... | 1994 | 8175720 |
| topoisomerase i action on the heterochromatic dna from the brine shrimp artemia franciscana: studies in vivo and in vitro. | the genomes of higher eukaryotes contain various amounts of tandem repeated dna sequences (satellite dna) typically located in the constitutive heterochromatin, the most highly condensed region of interphase chromosomes. we have previously demonstrated that an alui dna family of repeats is the major component of constitutive heterochromatin in the brine shrimp artemia franciscana. the analysis of cloned heterochromatic fragments revealed that this repetitive dna shows a stable curvature conferri ... | 1994 | 8192650 |
| regulatory features of protein synthesis in isolated mitochondria from artemia embryos. | optimal conditions were developed for measuring rates of protein synthesis in isolated mitochondria from encysted embryos of artemia franciscana to 1) identify the required chemical constituents, 2) assess the influence of extramitochondrial ph on protein synthesis, and 3) investigate potential mechanisms coordinating nuclear and mitochondrial gene expression. isolation procedures resulted in intact, highly coupled mitochondria [respiratory control ratio = 6.48 +/- 0.43 (se), n = 21]. requiremen ... | 1993 | 8285263 |
| similar alternative splicing events generate two sarcoplasmic or endoplasmic reticulum ca-atpase isoforms in the crustacean artemia franciscana and in vertebrates. | a second isoform of the artemia franciscana sarcoplasmic or endoplasmic reticulum ca-atpase has been identified through the isolation of cdna clones. this isoform differs from the previously identified one only at the c-terminal end of the protein. the last 6 amino acids of the former isoform change to 30 hydrophobic amino acids in the newly identified isoform that have the potentiality of being an additional transmembrane domain. the two a. franciscana isoforms are highly homologous to the two ... | 1993 | 8314776 |
| extension of enzyme half-life during quiescence in artemia embryos. | encysted gastrulae of artemia franciscana are known to enter a reversible state of quiescence in which biosynthetic and catabolic pathways are markedly suppressed. given that these embryos can survive months of anoxia, we investigated their ability to extend the half-life of cytochrome-c oxidase (cox), a key metabolic enzyme, during anoxia. we calculate that the half-life of cox is extended to 101 days under anoxia, an estimated 77-fold increase compared with aerobic values. during conditions of ... | 1993 | 8381619 |
| oxygen and ph regulation of protein synthesis in mitochondria from artemia franciscana embryos. | to identify factors responsible for the down-regulation of mitochondrial biosynthetic processes during anoxia in encysted artemia franciscana embryos, the effects of oxygen limitation and ph on protein synthesis were investigated in isolated mitochondria. at the optimal ph of 7.5, exposure of mitochondria to anoxia decreases the protein synthesis rate by 79%. rates were suppressed by a further 10% at ph 6.8, the intracellular ph (phi) measured under anoxia in vivo. matrix ph, measured under iden ... | 1996 | 8546685 |
| potential role in development of the major cysteine protease in larvae of the brine shrimp artemia franciscana. | encysted embryos and larvae of the brine shrimp artemia franciscana contain a cysteine protease which represents over 90% of the protease activity in these organisms. we have used immunocytochemical methods to determine the localization and potential role of the cysteine protease in development of young larvae. in prenauplius larvae, there is intense staining for the protease on the basal side of the epidermal layer in the posterior region and diffuse staining for the protease throughout the emb ... | 1995 | 8581922 |
| the sequence, organization, and evolution of the locusta migratoria mitochondrial genome. | the sequencing of the cloned locusta migratoria mitochondrial genome has been completed. the sequence is 15,722 bp in length and contains 75.3% a+t, the lowest value in any of the five insect mitochondrial sequences so far determined. the protein coding genes have a similar a+t content (74.1%) but are distinguished by a high cytosine content at the third codon position. the gene content and organization are the same as in drosophila yakuba except for a rearrangement of the two trna genes trnalys ... | 1995 | 8587138 |
| tissue-specific expression of two artemia franciscana sarco/endoplasmic reticulum ca-atpase isoforms. | the sarco/endoplasmic reticulum ca-atpase (serca) gene from artemia franciscana is transcribed into two mrnas that code for two different enzyme isoforms. we investigated the tissue-specific expression of each mrna by in situ hybridization of larval tissue sections. one of the isoforms is expressed in the muscle fibers of the appendages. the other isoform is generally expressed throughout all tissues of the larvae. the tissue distribution of these two isoforms is very similar to the one describe ... | 1996 | 8601691 |
| acute depression of mitochondrial protein synthesis during anoxia: contributions of oxygen sensing, matrix acidification, and redox state. | mitochondrial protein synthesis is acutely depressed during anoxia-induced quiescence in embryos of artemia franciscana. oxygen deprivation is accompanied in vivo by a dramatic drop in extramitochondrial ph, and both of these alterations strongly inhibit protein synthesis in isolated mitochondria. here we show that the oxygen dependence is not explained simply by blockage of the electron transport chain or by the increased redox state. whereas oxygen deprivation substantially depressed protein s ... | 1996 | 8631750 |
| mitochondrial differentiation during the early development of the brine shrimp artemia franciscana. | during the early development of artemia there is an increase in mitochondrial enzyme activities of about one order of magnitude, whereas the activities of two cytoplasmic enzymes tested as controls remain unaltered. the mitochondrial enzyme activation correlates with (i) large changes in mitochondrial morphology, (ii) a 5-fold increase in the amount of the h+-atp synthase beta-subunit and (iii) a dramatic increase in the steady-state level of mitochondrial mrnas, whereas mitochondrial rrna conce ... | 1996 | 8670064 |
| accumulation of trimethoprim, sulfamethoxazole, and n-acetylsulfamethoxazole in fish and shrimp fed medicated artemia franciscana. | in a previous paper (h.j. nelis, p. léger, p. sorgeloos, and a. p. de leenheer, antimicrob. agents chemother. 35:2486-2489, 1991) it was reported that two selected antibacterial agents, i.e., trimethoprim and sulfamethoxazole, can be efficiently bioencapsulated in nauplii of the brine shrimp artemia franciscana for administration to fish. this follow-up study showed that larvae of the sea bass and the turbot as well as postlarvae of the white shrimp accumulate the therapeutic agents in high quan ... | 1996 | 8807056 |
| profiles of nuclear and mitochondrial encoded mrnas in developing and quiescent embryos of artemia franciscana. | embryos of the brine shrimp artemia franciscana are able to withstand long bouts of environmental anoxia by entering a quiescent state during which metabolism is greatly depressed. recent evidence supports a global arrest of protein synthesis during quiescence. in this study we measured the amounts of mrna for a mitochondrial-encoded subunit of cytochrome c oxidase (cox i) and for nuclear-encoded actin during aerobic development, anaerobiosis, and aerobic acidosis (artificial quiescence imposed ... | 1996 | 8817476 |
| partial sequence of the shrimp penaeus notialis mitochondrial genome. | about half of the mitochondrial dna of the shrimp penaeus notialis (crustacea: decapoda) has been cloned (in 2 overlapping fragments of 7.9 kb and 1 kb) and partially sequenced. the gene content and arrangement are identical to that of the homologous domain in drosophila yakuba. intergenic nucleotides are scarce and a 982 bp non-coding sequence exhibit features similar to that of mtdna control regions. the gene organization and the trna structures differentiate the penaeus notialis mitochondrial ... | 1996 | 8881281 |
| partial sequence of the mitochondrial genome of the crustacean daphnia pulex. | a 4062-nucleotide (nt) fragment of the mitochondrial genome of the crustacean daphnia pulex was sequenced and found to contain the complete genes for eight trnas and five proteins (atp6, atp8, coii, coiii, nd3) and the partial sequence of coi. in combination with data described previously, approximately 50% of the d. pulex mitochondrial genome has been sequenced. the gene order in this half of the genome is identical to that of drosophila yakuba which differs from that of the other completely se ... | 1997 | 9000380 |
| polymorphism and structure of the gene coding for the alpha 1 subunit of the artemia franciscana na/k-atpase. | genomic clones coding for one of the two identified artemia franciscana na/k-atpase alpha subunits, the alpha 1 subunit, have been isolated. several overlapping clones were obtained, although their restriction maps showed a large heterogeneity. sequencing of their exons showed that they differ in up to 3.46% of their nucleotides in translated regions and 8.18% in untranslated regions. southern blot analysis of dna purified from different lots of a. franciscana cysts and from isolated individuals ... | 1997 | 9020888 |
| protein kinases in mitochondria of the invertebrate artemia franciscana. | the information concerning protein kinases in animal mitochondria is scarce and related only to mammals. no data are available for invertebrates. we demonstrate here the presence of casein kinase ii (ck ii) and camp-dependent protein kinase (pka) in the purified mitochondria of the crustacean artemia franciscana. whereas the mitochondrial ck ii showed the same characteristics of the cytosolic enzyme, mitochondrial pka had an apparent km for its substrate kemptide 1 order of magnitude lower than ... | 1997 | 9056227 |
| transcriptional regulation during the activation and development of artemia franciscana encysted embryos. | 1996 | 9087711 | |
| satellite dna from the brine shrimp artemia affects the expression of a flanking gene in yeast. | we have previously revealed that in the brine shrimp artemia franciscana an alui dna family of repeats, 113 bp in length, is the major component of the constitutive heterochromatin and that this repetitive dna shows a stable curvature that confers a solenoidal geometry on the double helix in vitro. it was suggested that this particular structure may play a relevant role in determining the condensation of the heterochromatin. in this report we have cloned hexamers of highly-repetitive sequence (a ... | 1997 | 9161405 |
| embryos of artemia franciscana survive four years of continuous anoxia: the case for complete metabolic rate depression | encysted gastrula embryos of the crustacean artemia franciscana have acquired an array of adaptations that enable them to survive a wide variety of environmental extremes.the present paper shows that at least 60 % survive 4 years of continuous anoxia at physiological temperatures (20­23 °c) when fully hydrated. although these embryos appear to carry on a metabolism during the first day of anoxia, no evidence for a continuing metabolism throughout the subsequent 4 years was obtained. duri ... | 1997 | 9318130 |
| effect of anaerobiosis on cysteine protease regulation during the embryonic-larval transition in | hydrated encysted embryos of the brine shrimp artemia franciscana have the ability to withstand years in anaerobic sea water using metabolic strategies that enable them to inactivate all cell metabolic activities and then to resume development when placed in aerobic sea water. however, this unique characteristic of artemia franciscana embryos is lost during a very short period, at the embryonic­larval transition period of development, coincident with the appearance of prenauplius larvae. thu ... | 1997 | 9318685 |
| reactivation of ubiquitination in artemia franciscana embryos during recovery from anoxia-induced quiescence | encysted gastrulae of artemia franciscana are known to enter a reversible state of quiescence promoted by anoxia, during which the half-life of cytochrome oxidase is prolonged up to 77-fold. this observation suggests that proteolytic pathways within mitochondria are inhibited, and indeed the suppression of the initial step in ubiquitin-mediated proteolysis under anoxia has been reported. given that active embryos require efficient degradation of macromolecules, we investigated the reactivation o ... | 1995 | 9319173 |
| mitochondrial transcription initiation in the crustacean artemia franciscana. | mitochondrial transcription has been studied in several vertebrate organisms, but so far no report on mitochondrial transcription initiation in invertebrates has been published. here we present an analysis of transcription initiation sites using in vivo-synthesized transcripts in the crustacean artemia franciscana. the mitochondrial genome of artemia has the same coding capacity as most animal mitochondrial genomes, and its overall organization is almost identical to that of drosophila. using in ... | 1997 | 9428705 |
| oxygen, phi and arrest of biosynthesis in brine shrimp embryos. | embryos of the brine shrimp artemia franciscana are able to withstand bouts of environmental anoxia for several years by entering a quiescent state, during which time metabolism is greatly depressed. within minutes of oxygen removal, intracellular ph (phi) drops at least 1.0 unit. this acidification has been strongly implicated in the arrest of both catabolic and anabolic processes in the cytoplasm. a global arrest of cytoplasmic translation accompanies the transition into anoxia or into aerobic ... | 1997 | 9429663 |
| quiescence in artemia franciscana embryos: reversible arrest of metabolism and gene expression at low oxygen levels. | depression of the production and consumption of cellular energy appears to be a prerequisite for the survival of prolonged bouts of anoxia. a correlation exists between the degree of metabolic depression under anoxia and the duration of anoxia tolerance. in the case of brine shrimp (artemia franciscana) embryos, oxygen deprivation induces a reversible quiescent state that can be tolerated for several years with substantial survivorship. a global arrest of cytoplasmic translation accompanies the ... | 1998 | 9510534 |
| bioencapsulation of two different vibrio species in nauplii of the brine shrimp (artemia franciscana) | two groups of nauplii from the brine shrimp (artemia franciscana) were enriched with different bacteria, and the dynamics of bacterial uptake by the nauplii were observed. this study showed that the efficiency of artemia nauplii in bioencapsulating bacteria strongly depends on the type of bacteria used, time of exposure, and status (live or dead) of the bacteria. | 1998 | 9603861 |
| identification of a mitochondrial rna polymerase in the crustacean artemia franciscana. | mitochondrial rna polymerase activity has been isolated from the crustacean artemia franciscana at two stages of development, dormant embryo and developing larva. the preparations were obtained from purified mitochondria and the polymerase activity was purified by heparin-sepharose chromatography. the presumed polymerase has a molecular mass of about 120 kda and a 7.4 s sedimentation coefficient. the biochemical characterization of the enzymatic reaction identified our rna polymerase preparation ... | 1998 | 9606962 |
| characterization of gamma-tubulin in artemia: isoform composition and spatial distribution in polarized cells of the larval epidermis. | microtubule arrangement is influenced by gamma-tubulin, a soluble protein of the eukaryotic cell cytosol and a component of microtubule-organizing centers. in this study, affinity purified antibodies to gamma-tubulin were prepared and their specificity demonstrated by immunostaining of western blots and in competitive elisas. when employed to label mouse fibroblasts, one or two brightly stained dots appeared in each cell, a pattern characteristic of centrosomes. antibody 9, raised to a conserved ... | 1998 | 9712263 |
| cloning and sequencing of an alpha-tubulin cdna from artemia franciscana: evidence for translational regulation of alpha-tubulin synthesis. | the brine shrimp, artemia franciscana, exhibits a limited number of tubulin isotypes which change little during early postgastrula growth. in order to better understand the synthesis of alpha-tubulins during artemia development, a cdna termed alphaat1 was cloned and sequenced. alignment analyses revealed that the polypeptide encoded by alphaat1 is similar to alpha-tubulins from other species. hybridization of alphaat1 to restriction-digested dna on southern blots produced a simple banding patter ... | 1998 | 9805005 |
| interactions of the ccaat-binding trimer nf-y with nucleosomes. | nf-y is a sequence-specific evolutionary conserved activator binding to ccaat boxes with high affinity and specificity. it is a trimer formed by nf-ya and two putative histone-like subunits, nf-yb and nf-yc, showing similarity to histones h2b and h2a, respectively. we investigated the relationships between nf-y and chromatin using an artemia franciscana chromatin assembly system with plasmids containing the major histocompatibility complex class ii ea promoter. the nf-y trimer, but not single su ... | 1999 | 9880503 |
| formation of a covalent nepsilon2-guanylylhistidyl reaction intermediate by the gtp:gtp guanylyltransferase from the brine shrimp artemia. | the chemical nature of the enzyme-nucleotide phosphoramidate reaction intermediate employed by the unique gtp:gtp guanylyltransferase from yolk platelets of artemia franciscana cysts to synthesize diguanosine tetraphosphate (gp4g) has been investigated. labeling of the enzyme with [alpha-32p]gtp followed by isolation of the labeled phosphoamino acid by periodate treatment and alkaline hydrolysis and comparison of the product with phosphoamino acid standards by thin-layer and ion-exchange chromat ... | 1999 | 9882433 |
| the synthesis of a small heat shock/alpha-crystallin protein in artemia and its relationship to stress tolerance during development. | fertilized oocytes of the brine shrimp artemia franciscana undergo either ovoviviparous or oviparous development, yielding free-swimming larvae (nauplii) or encysted gastrulae (cysts), respectively. encystment is followed by diapause, wherein metabolism is greatly reduced; the resulting cysts are very resistant to extreme stress, including desiccation and long-term anoxia. the synthesis of p26, a small heat shock/alpha-crystallin protein produced only in oviparously developing artemia, is shown ... | 1999 | 10068475 |
| isolation and characterization of the gene coding for artemia franciscana tata-binding protein: expression in cryptobiotic and developing embryos. | genomic and cdna clones coding for the artemia franciscana homolog of the tata box-binding protein (tbp) were isolated. the c-terminal region of the predicted protein displays up to 92% sequence identity with the conserved c-terminal regions of tbps from other species. the gene is divided in seven exons that expand over a region of 33 kb. the position of the four introns located in the conserved c-terminal region has been compared with those of other species. two of these introns have been gener ... | 1999 | 10366711 |
| mitochondrial genes collectively suggest the paraphyly of crustacea with respect to insecta. | complete sequences of seven protein coding genes from penaeus notialis mitochondrial dna were compared in base composition and codon usage with homologous genes from artemia franciscana and four insects. the crustacean genes are significantly less a + t-rich than their counterpart in insects and the pattern of codon usage (ratio of g + c-rich versus a + t-rich codon) is less biased. a phylogenetic analysis using amino acid sequences of the seven corresponding polypeptides supports a sister-taxon ... | 1999 | 10368442 |
| aph-1, a pou homeobox gene expressed in the salt gland of the crustacean artemia franciscana. | we characterized the first pou-homeoprotein in a crustacean (designated aph-1 for artemia pou-homeoprotein, embl y15070). the amino acid sequence of the aph-1 pou-domain is identical, except for two residues, to that of the two class iii pou proteins cf1-a (drosophila) and pou-m1 (bombyx mori). southern blot analysis suggests that crustaceans have only one class iii pou gene. rt-pcr and whole-mount in situ hybridization show that aph-1 mrna is present in larvae specifically in the salt gland, an ... | 1999 | 10495289 |
| experimental studies of extinction dynamics | extinction of populations occurs naturally, but global extinction rates are accelerating, making understanding extinction a high priority for conservation. extinction in experimental populations of brine shrimp (artemia franciscana) was measured to assess hypothesized extinction processes. greater initial population size, greater maximum population size supported by the environment, and lower variation in environmental conditions reduced the likelihood of extinction, as hypothesized. however, in ... | 1999 | 10550058 |
| hypoxia accelerates the development of respiratory regulation in brine shrimp - but at a cost | the ability to regulate o(2) uptake during exposure to acutely declining o(2) tensions developed early (stage 6) in the brine shrimp artemia franciscana and co-occurred with the appearance of a functional heart and gills. culture under chronic hypoxia (p(o2)=10 kpa) resulted in this regulation being brought forward both in development (to stage 3) and in time (hypoxia stimulated early growth), but still before heart and gill formation took place. consequently, it was suggested that the hypoxia-r ... | 1999 | 10574741 |
| regulatory features of transcription in isolated mitochondria from artemia franciscana embryos. | optimal conditions were developed for an in organello transcriptional run-on assay using mitochondria isolated from artemia franciscana embryos to investigate potential regulatory features of rna synthesis under conditions of anoxia-induced quiescence. transcription is not dependent on oxidative phosphorylation for maximal activity when exogenous atp is available. bona fide transcription products, as assessed by hybridization with specific mitochondrial cdnas from a. franciscana, are produced in ... | 1999 | 10600903 |
| high dna sequence variability at the alpha 1 na/k-atpase locus of artemia franciscana (brine shrimp): polymorphism in a gene for salt-resistance in a salt-resistant organism. | we previously reported that the na/k-atpase alpha 1 subunit coding gene showed signs of being a very polymorphic locus in artemia franciscana. this species is adapted to highly saline waters, and the na/k-atpase alpha 1 isoform presumably plays a key role in this adaptation. therefore, we were interested in further study of the alpha 1 na/k-atpase polymorphisms to examine whether they might be due to an adaptation to salt resistance driven by natural selection. using coding sequences from 10 gen ... | 2000 | 10677846 |
| a novel heparan sulphate with high degree of n-sulphation and high heparin cofactor-ii activity from the brine shrimp artemia franciscana. | with the aid of heparinase and heparitinases from flavobacterium heparinum and 13c and ih nmr spectroscopy it was shown that the heparan sulphate isolated from the brine shrimp artemia franciscana exhibits structural features intermediate between those of mammalian heparins and heparan sulphates. these include an unusually high degree of n-sulphation (with corresponding very low degree of n-acetylation), a relatively high content of iduronic acid residues (both unsulphated and 2-o-sulphated) and ... | 2000 | 10704986 |
| depression of nuclear transcription and extension of mrna half-life under anoxia in artemia franciscana embryos. | transcriptional activity, as assessed by nuclear run-on assays, was constant during 10 h of normoxic development for embryos of the brine shrimp artemia franciscana. exposure of embryos to only 4 h of anoxia resulted in a 79.3+/-1 % decrease in levels of in-vivo-initiated transcripts, and transcription was depressed by 88. 2+/-0.7 % compared with normoxic controls after 24 h of anoxia (means +/- s.e.m., n=3). initiation of transcription was fully restored after 1 h of normoxic recovery. artifici ... | 2000 | 10708633 |
| characterization of atp-dependent proteolysis in embryos of the brine shrimp, artemia franciscana. | under anoxia, embryos of artemia franciscana enter a state of quiescence. during this time protein synthesis is depressed, and continued degradation of proteins could jeopardize the ability to recover from quiescence upon return to favorable conditions. in this study, we developed an assay for monitoring atp/ ubiquitin-dependent proteolysis in order to establish the presence of this degradation mechanism in a. franciscana embryos, and to describe some characteristics that may regulate its functi ... | 2000 | 10791572 |
| crustacean (malacostracan) hox genes and the evolution of the arthropod trunk. | representatives of the insecta and the malacostraca (higher crustaceans) have highly derived body plans subdivided into several tagma, groups of segments united by a common function and/or morphology. the tagmatization of segments in the trunk, the part of the body between head and telson, in both lineages is thought to have evolved independently from ancestors with a distinct head but a homonomous, undifferentiated trunk. in the branchiopod crustacean, artemia franciscana, the trunk hox genes a ... | 2000 | 10804167 |
| posttranslationally modified tubulins and microtubule organization in hemocytes of the brine shrimp, artemia franciscana. | crustaceans possess blood cells (hemocytes) that mediate organismal defense and are analogous to vertebrate leukocytes. in order to more fully characterize these types of cells, hemocytes of the branchiopod crustacean, artemia franciscana, were analyzed. the data indicate that artemia have one type of hemocyte, ranging in morphology from compact and spherical to flat and spreading when examined in vitro. electron microscopy revealed many cytoplasmic granules in the hemocytes and only a limited n ... | 2000 | 10814999 |
| beta-hydroxybutyrate in developing nauplii of brine shrimp (artemia franciscana k.) under feeding and non-feeding conditions. | body content of beta-hydroxybutyrate, and individual dry mass, carbon content, and survival rate, were studied in developing nauplii of the brine shrimp artemia franciscana k. from hatching to 96-97 h post hatching at 27 +/- 1 degrees c. the effect of two diets was studied in the experiment: super selco (ss) with a high lipid content; and protein selco (ps) with a high protein content. a starving group (s) was used as reference. the level of beta-hydroxybutyrate at hatching was 0.6 nmol.ind-1; i ... | 2000 | 10840642 |
| the heat shock response of adult artemia franciscana. | 2000 | 10880872 | |
| a serum response factor homologue is expressed in ectodermal tissues during development of the crustacean artemia franciscana. | complementary dna clones have been isolated from the crustacean artemia franciscana coding for a serum response factor (srf)-homologue that is more than 96% identical to human and drosophila melanogaster srfs in their mads boxes. the srf homologue is expressed in ectodermal tissues, as determined by in situ hybridization experiments. a srf-binding site has been identified in the promoter region of the actin403 gene that is also expressed in ectodermal tissues, in accordance with its transcriptio ... | 2000 | 10960789 |
| thermal resistance, developmental rate and heat shock proteins in artemia franciscana, from san francisco bay and southern vietnam. | cysts (encysted gastrula embryos) of artemia franciscana collected from salterns in san francisco bay, california, usa (sf) were inoculated into much warmer growth ponds in the mekong delta region of vietnam (v) in 1996. v adults arising directly from these cysts during 17 april to 15 may produced their own cysts, which were collected, processed and stored until shipped to the usa for study. adults grown in the laboratory from sf cysts (those used for the inoculation) were less resistant to high ... | 2000 | 10962067 |
| long-term anoxia in encysted embryos of the crustacean, artemia franciscana: viability, ultrastructure, and stress proteins. | cells of encysted embryos of artemia franciscana, the brine shrimp, are among the most resistant of all animal cells to extremes of environmental stress. we focus here on their ability to survive continuous anoxia for periods of years, during which their metabolic rate is undetectable. we asked whether their impressive tolerance was reflected in changes at the ultrastructural level. the ultrastructure of encysted embryos previously experiencing 38 days and 3.3 years of anoxia was compared with t ... | 2000 | 10994789 |
| cloning and characterization of sarco/endoplasmic reticulum ca(2+)-atpase (serca) from crayfish axial muscle. sarco/endoplasmic reticulum ca(2+)-atpase. | the discontinuous pattern of muscle growth during the moulting cycle of a freshwater crustacean (the crayfish procambarus clarkii) was used as a model system to examine the regulation of the expression of sarco/endoplasmic reticulum ca(2+)-atpase (serca). we describe the cloning, sequencing and characterization of a novel serca cdna (3856 bp) obtained from crayfish axial abdominal muscle by reverse transcription/polymerase chain reaction (rt-pcr) followed by rapid amplification of cdna ends (rac ... | 2000 | 11044380 |
| characterization of a novel heterodimeric cathepsin l-like protease and cdna encoding the catalytic subunit of the protease in embryos of artemia franciscana. | embryos and larvae of the brine shrimp, artemia franciscana, contain a novel cathepsin l-like cysteine protease (acp) composed of 28.5- and 31.5-kda subunits. both subunits of the acp are glycosylated, and seven isoforms of the protease were identified by isoelectric focusing with pi values ranging from 4.6 to 6.2. several clones containing sequences coding for the 28.5-kda subunit of the acp were isolated from an artemia embryo cdna library in lambda zap ii. one clone of 1229 bp, with an open r ... | 2001 | 11235917 |
| diguanosine nucleotide metabolism and the survival of artemia embryos during years of continuous anoxia. | encysted embryos of the primitive crustacean, artemia franciscana, are remarkably resistant to a variety of harsh environmental conditions, including continuous anoxia for periods of years at physiological temperatures and water contents. previous study produced no evidence of an ongoing anoxic metabolism, suggesting that these embryos remained viable in spite of the lack of detectable free energy flow and biosynthesis. that seeming violation of a major axiom of cell biology and biochemistry pro ... | 2001 | 11248674 |
| intestinal uptake of lipovitellin from brine shrimp (artemia franciscana) by larval inland silversides (menidia beryllina) and striped bass (morone saxatilis). | intestinal uptake of lipovitellin (lv) from brine shrimp (artemia franciscana) in larval inland silversides (menidia beryllina) and striped bass (morone saxatilis) was described using immunocytochemistry. polyclonal antisera were raised against two subunits of lv (lv68 and lv190). when tested by immunocytochemistry, anti-lv68 showed cross-reactivity with some of the pancreatic cells especially in inland silversides. therefore anti-lv190 was used to localize immunoreactive lv. inland silversides ... | 1998 | 11253815 |
| uptake and processing of a vibrio anguillarum bacterin in artemia franciscana measured by elisa and immunohistochemistry. | nauplii of artemia franciscana were incubated in two different concentrations (undiluted and 1:9 in autoclaved sea water) of a divalent bacterin composed of two different serovars of vibrio anguillarum. in order to investigate uptake and further processing of a bacterin in the live feed organism a. franciscana, immunohistochemistry was applied, visualising the presence of whole bacterial cells and antigens from the bacterin in individual nauplii. by using elisa, it was shown that approximately 1 ... | 2001 | 11271599 |
| identification of the s6 kinase activity stimulated in quiescent brine shrimp embryos upon entry to preemergence development as p70 ribosomal protein s6 kinase: isolation of artemia franciscana p70s6k cdna. | we previously demonstrated that a protein kinase responsible for phosphorylating 40s ribosomal subunits is activated in quiescent artemia franciscana embryos within 15 min of restoration of normal tonicity and incubation at 30 degrees c. here, we identify the activated s6 kinase as a. franciscana p70 ribosomal s6 kinase (p70s6k) subsequent to the isolation of an artemia p70s6k cdna. the protein conceptually translated from cdna has 70% similarity and 64% identity to both drosophila melanogaster ... | 2001 | 11310561 |
| characterization of a functional serum response element in the actin403 gene promoter from the crustacean artemia franciscana. | the serum response factor (srf) activates expression of several genes in response to growth factors present in serum. srf also regulates the expression of tissue-specific genes, including those in vertebrate muscles. an srf-binding site (carg box) present in the artemia franciscana actin403 promoter was shown to be necessary for transcriptional activity in cultured cells from drosophila melanogaster and mammals. this dna region bound mammalian and drosophila srfs in vitro and mediated transcript ... | 2001 | 11322877 |
| cytogenetic proof that the brine shrimp artemia franciscana (crustacea, branchiopoda) is found in argentina. | artemia brine shrimps are commercially important and they have been extensively studied. this branchiopod crustacean is extensively used in aquaculture and other commercial and applied practices. the genus also awakes an increasing interest worldwide as an experimental model in other basic areas of research such as evolution and cytogenetics. in the present work adult male meiosis and nauplii mitotic cells in two artemia populations from argentina (mar chiquita and las tunas, córdoba province) a ... | 2000 | 11338428 |
| isolation of a cdna encoding a putative sparc from the brine shrimp, artemia franciscana. | sparc (secreted protein, acidic, rich in cysteine) is an extracellular matrix-associated and anti-adhesive glycoprotein extensively studied in vertebrates. its presence among invertebrates has been reported in nematodes and flies. we cloned a cdna containing a complete open reading frame for sparc from the brine shrimp, artemia franciscana. the amino acid sequence identity between the artemia and the fly sparcs was 55%, whereas that of the artemia and the nematode proteins was 45%. artemia and v ... | 2001 | 11368900 |
| development of new heparin-like compounds and other antithrombotic drugs and their interaction with vascular endothelial cells. | the anticlotting and antithrombotic activities of heparin, heparan sulfate, low molecular weight heparins, heparin and heparin-like compounds from various sources used in clinical practice or under development are briefly reviewed. heparin isolated from shrimp mimics the pharmacological activities of low molecular weight heparins. a heparan sulfate from artemia franciscana and a dermatan sulfate from tuna fish show a potent heparin cofactor ii activity. a heparan sulfate derived from bovine panc ... | 2001 | 11378657 |
| toxicity, bioaccumulation, and interactive effects of organotin, cadmium, and chromium on artemia franciscana. | the effects of three organotin compounds-trimethyltin chloride, dimethyltin dichloride, and dibutyltin diacetate-and two heavy metals-cadmium and hexavalent chromium-on artemia franciscana mortality are investigated in this study. of all the compounds tested in this work, trimethyltin chloride was, by far, the most toxic. the toxicity order for the five compounds was trimethyltin chloride > potassium dichromate > dimethyltin dichloride > dibutyltin diacetate > cadmium chloride. the big differenc ... | 2001 | 11386732 |
| nuclear p26, a small heat shock/alpha-crystallin protein, and its relationship to stress resistance in artemia franciscana embryos. | the role of the small heat shock/alpha-crystallin protein, p26, in transcription in artemia franciscana embryos was examined using isolated nuclei, containing either control or elevated levels of p26, in transcription run-on assays. heat shock or anoxia in vivo and acid ph in vitro were used to transfer p26 into nuclei. the results suggest that parameters other than, or in addition to, p26 are responsible for the reduced transcription rates observed and that decreases in phi are involved. in viv ... | 2001 | 11507116 |
| embryogenesis, hatching and larval development of artemia during orbital spaceflight. | developmental biology studies, using gastrula-arrested cysts of the brine shrimp artemia franciscana, were conducted during two flights of the space shuttle atlantis (missions sts-37 and sts-43) in 1991. dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fix ... | 1994 | 11537922 |
| effect of microgravity and hypergravity on embryo axis alignment during postencystment embryogenesis in artemia franciscana (anostraca). | cysts of brine shrimp attached with a liquid adhesive to 12-mm diameter glass coverslips in a syringe-type fluid processing apparatus were flown aboard the nasa space shuttle discovery, flight sts-60, from 3-11 february 1994, and were allowed to undergo postencystment embryogenesis and to hatch in microgravity. the shuttle flight and the ground-based control coverslips with attached cysts were parallel to the earth's surface during incubation in salt water. based on the position of the cyst shel ... | 1995 | 11539283 |
| influence of trehalose on the molecular chaperone activity of p26, a small heat shock/alpha-crystallin protein. | encysted embryos of the primitive crustacean artemia franciscana are among the most resistant of all multicellular eukaryotes to environmental stress, in part due to massive amounts of a small heat shock/alpha-crystallin protein (p26) that acts as a molecular chaperone. these embryos also contain very large amounts of the disaccharide trehalose, well known for its ability to protect macromolecules and membranes against damage due to water removal and temperature extremes. therefore, we looked fo ... | 2001 | 11599574 |
| international study on artemia. lxii. genomic relationships between artemia franciscana and a. persimilis, inferred from chromocentre numbers. | chromocentres, i.e. heavily stainable heterochromatic areas with highly repetitive dna (a 130-bp repeat in the order of 6 x 105 copies per haploid genome) observed in the resting nucleus, are a reliable taxonomic trait and a good marker for speciation in artemia. this chromosome marker was evaluated in populations of two new world sibling species: a. franciscana, from north, central and south america, and a. persimilis from argentina. artemia persimilis showed the characteristically low average ... | 2001 | 11703507 |
| small heat shock protein p26 associates with nuclear lamins and hsp70 in nuclei and nuclear matrix fractions from stressed cells. | the small heat shock/alpha-crystallin protein p26 undergoes nuclear translocation in response to stress in encysted embryos of the brine shrimp artemia franciscana. about 50% of total p26 translocates to nuclei in embryos treated with heat shock or anoxia, and in embryo homogenates incubated at low ph. nuclear fractionation shows that the majority of nuclear p26 and a nuclear lamin are associated with the nuclear matrix fraction. to further explore the roles of p26 and other hsps in stabilizing ... | 2002 | 11813265 |
| comparing the acute response to cadmium toxicity of nauplii from different populations of artemia. | the lethal responses to cadmium of instar ii nauplii from eight populations of artemia belonging to the species artemia franciscana, artemia salina, artemia persimilis, and artemia parthenogenetica have been compared. generalized linear models were used to fit mortality. the model indicates that there is a relationship between species, type of population, and mortality rate. the two populations of a. franciscana were the most sensitive to cadmium toxicity (median lethal concentration, lc50, of 9 ... | 2002 | 11833813 |
| salt toxicosis in ruddy ducks that winter on an agricultural evaporation basin in california. | agricultural evaporation basins are used as a means to dispose of highly saline underground-tile-drainage water in the san joaquin valley (california, usa). the hypersaline water conditions encourage high aquatic invertebrate production, primarily brine shrimp (artemia franciscana), which attract birds to these sites. cool winter temperatures (< 4 c) and hypersaline water conditions (> 70,000 mumhos/cm) resulted in feather salt encrustation and salt toxicosis in ruddy ducks (oxyura jamaicensis). ... | 2002 | 11838203 |
| functional analysis of a small heat shock/alpha-crystallin protein from artemia franciscana. oligomerization and thermotolerance. | oviparously developing embryos of the brine shrimp, artemia franciscana, synthesize abundant quantities of a small heat shock/alpha-crystallin protein, termed p26. wild-type p26 functions as a molecular chaperone in vitro and is thought to help encysted artemia embryos survive severe physiological stress encountered during diapause and anoxia. full-length and truncated p26 cdna derivatives were generated by pcr amplification of p26-3-6-3, then cloned in either pet21(+) or prsetc and expressed in ... | 2002 | 11846795 |
| yolk platelets in artemia embryos: are they really storage sites of immature mitochondria? | we have used semi-quantitative polymerase chain reaction (pcr) technology to determine the mitochondrial dna (mtdna) content of yolk platelets isolated from embryos of the brine shrimp, artemia franciscana, and ultrastructural analysis of yolk platelet formation to determine whether these organelles contain mitochondria as reported previously. using six different isolation and purification protocols, we found one yolk platelet preparation to be devoid of mtdna, while four yolk platelet preparati ... | 2002 | 12031476 |
| transactivation domains are not functionally conserved between vertebrate and invertebrate serum response factors. | the transcription factor serum response factor (srf) regulates expression of growth factor-dependent genes and muscle-specific genes in vertebrates. homologous factors regulate differentiation of some ectodermic tissues in invertebrates. to explore the molecular basis of these different physiological functions, the functionality of human, drosophila melanogaster and artemia franciscana srfs in mammalian cells has been compared in this article. d. melanogaster and, to a lesser extend, a. francisc ... | 2002 | 12153563 |
| isolation of prorocentrum lima (syn. exuviaella lima) and diarrhetic shellfish poisoning (dsp) risk assessment in the gulf of california, mexico. | a benthic toxic dinoflagellate identified as prorocentrum lima (syn. exuviaella lima), and designated as strain prl-1, was isolated from the coast of el pardito (coyote) island in baja california sur, mexico, after a fisherman poisoning incident involving consumption of liver from lutjanus colorado, and mycteroperca prionura fish. purification and culturing was done in es-si medium, under 12:12 light/dark cycle (4 x 20 w cool-white fluorescent lamps), at 22 degrees c and constant stirring during ... | 2002 | 12165314 |
| [allozymatic variation in crustacea artemia franciscana (anostraca: artemiidae) of freat salt lake in different experimental conditions]. | starch gel electrophoresis was used to analyze the allelic variability of four polymorphic loci (lap-2, lap-3, pgm and gpi) from a single population of artemia franciscana (kellogg, 1906) from the great salt lake (utah, usa), cultured under eight different experimental conditions. the organisms were cultured to the adult stage under a 2 x 2 x 2 experimental design (22 and 30 degrees c; 30 and 60 ppt salinity; and dunaliella sp. and spirulina sp. as food). there were significant differences in al ... | 2002 | 12298270 |
| expression of the artemia trachealess gene in the salt gland and epipod. | the drosophila trachealess gene encodes a basic-helix-loop-helix-pas transcription factor that controls the formation of the trachea and salivary duct. an ortholog of trachealess was identified in the brine shrimp, artemia franciscana, and was shown to be highly conserved by sequence identity. expression of artemia trachealess was observed at two sites during development: the naupliar salt gland and the juvenile thoracic epipod. these two organs function at their respective times of development ... | 2008 | 12356264 |
| regiospecific distribution of fatty acids in triacylglycerols of artemia franciscana nauplii enriched with fatty acid ethyl esters. | this paper reports the positional distribution of fatty acids in triacylglycerols (tag) of artemia franciscana nauplii enriched with each of palmitic (16:0), oleic (18:1n-9), linoleic (18:2n-6), linolenic (18:3n-3), eicosapentaenoic (20:5n-3), and docosahexaenoic (22:6n-3) acid ethyl esters. tag extracted from the enriched and unenriched nauplii were subjected to regiospecific analysis to determine the fatty acid compositions of the sn-1(3) and sn-2 positions of tag. in the unenriched nauplii, 1 ... | 2002 | 12381381 |