| heterosis and the lack of coadaptation in drosophila nasuta. | natural populations of drosophila nasuta are polymorphic for several paracentric inversions. two non-overlapping inversions on the third chromosome (iii-2 and iii-35) are heterotic in both laboratory and natural populations and display an extreme case of linkage disequilibrium. intra- and interpopulation crosses involving standard and inverted gene orders of the iii-2 and iii-35 inversions were made to test if the polygenic complexes within these inversions are coadapted. the inversion heterozyg ... | 2004 | 1774187 |
| glue proteins in drosophila nasuta. | larval glue protein fractions of drosophila nasuta nasuta were analyzed by sodium dodecyl sulfate (sds)-polyacrylamide gel electrophoresis. seven major and at least four minor glue protein fractions were recognized. six of the major fractions are glycosylated. they migrate as three prominent doublets (greater than 100, 43, and 30/28 kd). the synthesis of traceable amounts of these major fractions begins already during the second as well as during the early stages of the third larval instar. the ... | 2011 | 3147658 |
| adaptation to larval crowding in drosophila ananassae and drosophila nasuta nasuta: increased larval competitive ability without increased larval feeding rate. | the standard view of adaptation to larval crowding in fruitflies, built on results from 25 years of multiple experimental evolution studies on drosophila melanogaster, was that enhanced competitive ability evolves primarily through increased larval feeding and foraging rate, and increased larval tolerance to nitrogenous wastes, at the cost of efficiency of food conversion to biomass. these results were at odds from the predictions of classical k-selection theory, notably the expectation that sel ... | 2016 | 27350686 |
| genetic variation in natural island populations of members of the drosophila nasuta and drosophila ananassae subgroups. | | 1968 | 5242114 |
| divergence of the gene aly in experimentally evolved cytoraces, the members of the nasuta-albomicans complex of drosophila. | we generated cytoraces by crossing the chromosomal races (drosophila nasuta nasuta and drosophila nasuta albomicans) of the nasuta subgroup of drosophila and maintained the offspring over many generations through sibling mating. these cytoraces, along with their parents, are members of the nasuta-albomicans complex of drosophila. the gene always early (aly) is one of the rapidly evolving genes in the genus drosophila and plays a central role in regulating meiosis. here we examined the rate of mo ... | 2014 | 24645631 |
| last mated male sperm precedence in doubly mated females is not ubiquitous: evidence from sperm competition in laboratory populations of drosophila nasuta nasuta and drosophila nasuta albomicans. | | 2013 | 23970089 |
| racial divergence of a rare laboratory-evolved centromeric fission cytorace of nasuta-albomicans complex of drosophila. | fissioncytorace-1, a member of the nasuta-albomicans complex of drosophila is an evolutionary product of centric fission, which had occurred in the chromosome x3 of cytorace 1, a hydridization product of drosophila nasuta nasuta male (2n=8) and drosophila nasuta albomicans female (2n=6). cytorace 1 (males 2n=7; females 2n=6) has inherited this chromosome from its d. n. albomicans parent. the chromosome x3 of d. n. albomicans is a derivative of a centric fusion between the acrocentric chromosome ... | 2010 | 20795370 |
| chromosomal localization of autosomal mutations in drosophila nasuta nasuta and drosophila nasuta albomicans. | | 2005 | 15876587 |
| evolutionary experimentation through hybridization under laboratory condition in drosophila: evidence for recombinational speciation. | drosophila nasuta nasuta (2n = 8) and drosophila nasuta albomicans (2n = 6) are a pair of sibling allopatric chromosomal cross-fertile races of the nasuta subgroup of immigrans species group of drosophila. interracial hybridization between these two races has given rise to new karyotypic strains called cytorace 1 and cytorace 2 (first phase). further hybridization between thailand strain of d. n. albomicans and d. n. nasuta of coorg strain has resulted in the evolution of two more cytoraces, nam ... | 2003 | 14519211 |
| hybridization and introgression of the genomes of drosophila nasuta and drosophila albomicans: evolution of new karyotypes. | drosophila nasuta (2n = 8) and drosophila albomicans (2n = 6) are cross-fertile allopatric sibling chromosomal races of the nasuta subgroup of drosophila. hybrids of these races can be maintained for any number of generations. some of the introgressed hybrid lineages of d. nasuta and d. albomicans, after passing through a transient phase of karyotypic polymorphism, ended up with a stable karyotype whose composition is different from those of the parental races. such hybrid populations were calle ... | 2003 | 12897869 |
| incipient sexual isolation in the nasuta-albomicans complex of drosophila: mating preference in male-, female- and multiple-choice mating experiments. | interracial divergence is an important facet of speciation. the nasuta-albomicans complex of drosophila with sixteen morphologically identical, karyotypically different but cross-fertile races is an excellent system to study a few dimensions of raciation. drosophila nasuta nasuta, drosophila nasuta albomicans, cytorace 1, cytorace 2, cytorace 3 and cytorace 4 of this subgroup have been subjected to male-, female- and multiple-choice mating experiments. out of 8456 crosses conducted, 7185 had suc ... | 2001 | 11568482 |
| genetic and biochemical analysis of brown eye mutation in drosophila nasuta nasuta and drosophila nasuta albomicans. | by analyzing the progeny of crosses involving brown eye mutants and the wild types in two members of drosophila nasuta subgroup namely d. n. nasuta and d. n. albomicans we could show that the mutant gene is recessive, located in the chromosome 2 and the alleles of this gene are present at different loci. a study of fitness in the eye color mutants in comparison with the wild types revealed that d. n. nasuta mutant has higher viability at both 25+/-1 degrees c and ambient temperatures; while d. n ... | 2000 | 11430487 |
| autoradiographic study of transcription and dosage compensation in the sex and neo-sex chromosome of drosophila nasuta nasuta and drosophila nasuta albomicans. | cellular autoradiography is used to study the transcription patterns of the polytene x chromosomes in drosophila nasuta nasuta and d. n. albomicans. d. n. nasuta, with 2n = 8, includes a pair of complete heteromorphic sex chromosomes, whereas d. n. albomicans, with 2n = 6, has a pair of metacentric neo-sex chromosomes representing incomplete heteromorphic sex chromosomes. the neo-x chromosome has two euchromatic arms, one representing the ancestral x while the other represents the ancestral auto ... | 2001 | 11269359 |
| incipient sexual isolation in the nasuta-albomicans complex of drosophila: no-choice experiments. | drosophila nasuta nasuta and drosophila nasuta albomicans are cross-fertile races of drosophila. hybridization between these races in the laboratory has given rise to new races (cytoraces), among which karyotypic composition differs from one another and also from those of the parental races. in this study, we search for the evidence of incipient reproductive isolation among the parental races and four cytoraces by assessing the fraction of no-matings, mating latency and copulation duration in al ... | 2001 | 11255515 |
| patterns of replication in the neo-sex chromosomes of drosophila nasuta albomicans. | drosophila nasuta albomicans (with 2n = 6), contains a pair of metacentric neo-sex chromosomes. phylogenetically these are products of centric fusion between ancestral sex (x, y) chromosomes and an autosome (chromosome 3). the polytene chromosome complement of males with a neo-x- and neo-y-chromosomes has revealed asynchrony in replication between the two arms of the neo-sex chromosomes. the arm which represents the ancestral x-chromosome is faster replicating than the arm which represents ances ... | 2000 | 11022223 |
| electron microscopic band-interband pattern of polytene chromosomes in drosophila nasuta albomicans. 1. salivary gland chromosome 2r. | the band-interband pattern of salivary gland chromosome 2r in drosophila nasuta albomicans (division 53-83) was studied by light (lm) and electron microscopy (em) using squash preparations and surface-spread polytene (ssp) chromosome preparations, respectively. lm and em maps were compiled. based on the digitized em patterns of five homologous ssp chromosomes a computerized chromosome map was plotted. the em pattern analysis showed a total number of 662 chromosome bands with an almost 98% increa ... | 1991 | 2029854 |
| electron microscopic band-interband pattern of polytene chromosomes in drosophila nasuta albomicans. 2. salivary gland chromosome 2l. | the band-interband pattern (division 28-52) of salivary gland chromosome 2l in drosophila nasuta albomicans was studied by light (lm) and electron microscopy (em) using squash preparations and surface-spread polytene (ssp) chromosome preparations, respectively. lm and em maps were complied. based on the digitized em patterns of five homologous ssp chromosomes a computerized em chromosome map was plotted. the em pattern analysis showed a total number of 479 chromosome bands with an almost 83% inc ... | 1991 | 1807929 |
| inversion polymorphism in populations of drosophila sulphurigaster albostrigata and drosophila nasuta albomicans from phuket, thailand. | two species of the drosophila nasuta subgroup of the drosophila immigrans group, d. sulphurigaster albostrigata and d. nasuta albomicans were investigated in this study. collections of both species were made from phuket, thailand. both species have similar salivary chromosomes, with four autosomal arms and one sex chromosome arm, and both are highly polymorphic for paracentric inversions. d.s. albostrigata accounted for the majority of the isolines collected and exhibited the greater number of i ... | 1990 | 2083846 |
| [molecular phylogenetic relationships of drosophila immigrans species group based on h2a-h2b spacer and cyt b sequences]. | in order to investigate molecular phylogenetic relationships of drosophila immigrans species group, nucleotide sequences of h2a-h2b spacer regions and partial nucleotide sequences of cytochrome b gene for five specieses subgroup in drosophila immigrans species group and d. hydei which was selected as outgroup were acquired. phylogenetic trees were reconstructed using maximum parsimony, maximum likelihood, neighbor joining and bayesian methods based on h2a-h2b and cyt b dna sequences. the results ... | 2006 | 16944604 |
| rapid evolution of a few members of nasuta-albomicans complex of drosophila: study on two candidate genes, sod1 and rpd3. | drosophila nasuta nasuta (2n = 8) and d. n. albomicans (2n = 6) are morphologically identical, cross fertile and karyotypically dissimilar pair of chromosomal races belonging to nasuta subgroup of immigrans group of drosophila. interracial hybridization between these two races yielded karyotypically stabilized newly evolved cytoraces with new combinations of chromosomes and dna content, and are called nasuta-albomicans complex of drosophila. along with many other features, striking plasticity in ... | 2013 | 23619741 |
| influence of mating histories and age on female remating behaviour in a few closely related species of drosophila nasuta subgroup. | female remating with more than one male leads to coexistence of sperm from different males in the same female, thus creating a selection pressure on sperm. to understand the extent of divergence in the reproductive behaviour among closely related species, in the present study, the influence of first mating histories like mating latency, duration of copulation and age of flies have been analysed on female remating behaviour in closely related drosophila nasuta subgroup species with varying levels ... | 2012 | 22670479 |
| male accessory gland secretory protein polymorphism in natural populations of drosophila nasuta nasuta and drosophila sulfurigaster neonasuta. | male accessory gland secretory protein polymorphism was analysed in natural populations of drosophila nasuta nasuta and d. sulfurigaster neonasuta for the first time, using sds-page to score polymorphism of these proteins in 2788 individuals of d. n. nasuta and 2232 individuals of d. s. neonasuta from 12 different populations from southern india. a total of 25 and 18 variant protein phenotypes were identified in d. n. nasuta and d. s. neonasuta, respectively. protein fractions of group iii were ... | 2007 | 18305341 |
| the speciation history of the drosophila nasuta complex. | the drosophila nasuta subgroup of the immigrans species group is widely distributed throughout the south-east asian region, consisting of morphologically similar species with varying degrees of reproductive isolation. here, i report nucleotide variability data for five x-linked and two mtdna loci in eight taxa from the nasuta subgroup, with deeper sampling from d. albomicans and its sister species d. nasuta. phylogenetic relationships among these species vary among different genomic regions, and ... | 2006 | 17014741 |
| introgressive hybridization and evolution of a novel protein phenotype: glue protein profiles in the nasuta-albomicans complex of drosophila. | glue proteins are tissue-specific proteins synthesized by larval salivary gland cells of drosophila. in drosophila nasuta nasuta and d. n. albomicans of the nasuta subgroup, the genes that encode the major glue protein fractions are x-linked. in the present study, these x-linked markers have been employed to trace the pattern of introgression of d. n. nasuta and d. n. albomicans genomes with respect to the major glue protein fractions in their interracial hybrids, called cytoraces. these cytorac ... | 2006 | 16809836 |
| hybridization, transgressive segregation and evolution of new genetic systems in drosophila. | introgressive hybridization facilitates incorporation of genes from one species into the gene pool of another. studies on long-term effects of introgressive hybridization in animal systems are sparse. drosophila nasuta (2n = 8) and d. albomicans (2n = 6)-a pair of allopatric, morphologically almost identical, cross-fertile members of the nasuta subgroup of the immigrans species group-constitute an excellent system to analyse the impact of hybridization followed by transgressive segregation of pa ... | 2003 | 15133193 |
| male accessory gland secretions in hybrids of drosophila nasuta nasuta and d. n. albomicans neither show luxuriance nor breakdown. | male accessory gland secretions, which have a role to play in reproduction have been investigated. the number of cells that make up the gland, the quantity of secretions synthesized and the influence of these secretions on fecundity of the female have been studied in d. n. nasuta, d. n. albomicans and their f1 progeny. the results revealed that the hybrid males show a trend towards d. n. nasuta in the synthesis of male accessory gland proteins and the fecundity of the female is influenced more b ... | 2002 | 12635712 |
| male accessory gland secretory proteins in a few members of the drosophila nasuta subgroup. | male accessory gland secretory proteins in seven members of the drosophila nasuta subgroup have been analyzed by sds-page. the study revealed remarkable simplicity in the patterns. the protein fractions, which migrate in three groups, could be categorized as "major" and "minor." the number of major fractions varies from a maximum of eight to a minimum of four. group i consists of high molecular weight fractions, and group iii, low molecular weight fractions. among different members analyzed, the ... | 2001 | 11521511 |
| racial divergence in abdominal bristles among parental races and newly evolved cytoraces of nasuta-albomicans complex of drosophila. | cytoraces are the products of interracial hybridization between drosophila nasuta nasuta and d. nasuta albomicans. these races differ from their parents in the chromosome composition, mating preference, certain fitness phenotypes and also a few morphophenotypic traits. now, these cytoraces are passing through 330 generations. racial divergence in the 4th and 5th abdominal bristles among the parental races and the newly evolved cytorace 1 and 2 is reported. the results revealed that the parental ... | 2000 | 11411052 |
| [a study of its sequence as a molecular marker in the phylogeny of drosophila nasuta subgroup]. | a total of 1.1 kb including whole its (intertranscribed spacer), part of 5.8s rdna and 2s rdna were sequenced. the results reveal that d. pallidifrons, taxon i and taxon j share the same sequence, and d. albomicans and d. s. neonasuta have the other same one. among the sequences, there were a handful of insertions, deletions and substitutions. insertions and deletions occur mainly between outgroup and ingroups; yet only 1 insertion and 12 deletions were detected in d. niveifrons, and 1 deletion ... | 2000 | 10883535 |
| male accessory gland secretory proteins in nasuta subgroup of drosophila: nature and sds-page patterns. | male accessory gland secretory proteins in seven members of drosophila nasuta subgroup were analyzed by sds-page in combination with different staining techniques such as cbb-r250, silver, pas, pas-silver and zinc-imidazole reverse staining. based on coomassie blue patterns the protein fractions could be classified in to 3 major groups namely group i, group ii as well as group iii; with high molecular weight fractions falling into group i and low molecular weight fractions into group iii. all th ... | 1999 | 10709324 |
| phylogeny and evolution of the drosophila nasuta subgroup based on mitochondrial nd4 and nd4l gene sequences. | the sequences of the mitochondrial nd4 gene (1339 bp) and the nd4l gene (290 bp) were determined for all the 14 extant taxa of the drosophila nasuta subgroup. the average a + t content of nd4 genes is 76.5% and that of nd4l genes is 83.5%. a total of 114 variable sites were scored. the nd4 gene sequence divergence ranged from 0 to 5.4% within the subgroup. the substitution rate of the nd4 gene is about 1.25% per million years. the base substitution of the genes is strongly transition biased. nei ... | 1999 | 10620413 |
| aging alters properties of the circadian pacemaker controlling the locomotor activity rhythm in males of drosophila nasuta. | effects of aging on the circadian rhythm of locomotor activity in males of drosophila nasuta were investigated. the adult life of males was divided in 1-3 stages according to spontaneous changes in free-running period tau in constant darkness (dd): stage 1, days 1-19; stage 2, days 20-36; stage 3, days 37-43. stage 1 was characterized by a bimodal activity pattern with a short light-induced morning peak and a prolonged evening peak when the flies were entrained to light-dark cycles of 12 hours o ... | 1999 | 10584175 |
| does evolution reduce the body size? a study of the four members of newly evolved nasuta-albomicans complex of drosophila. | our long range interracial hybridization experiments between a pair of cross fertile races, drosophila nasuta (2n = 8) and d. albomicans (2n = 6) have resulted in the evolution of two new karyotypic strains under laboratory conditions, which are named as cytorace 1 and cytorace 2. these cytoraces harbor chromosomes from both parents. here, we compare the body size of the parental races and newly evolved cytoraces and the relationship between the body size and fitness. analysis reveals that the p ... | 1999 | 10483088 |
| the period gene: high conservation of the region coding for thr-gly dipeptides in the drosophila nasuta species subgroup. | in this study, the region corresponding to the thr-gly region of the period (per) gene in the drosophila nasuta subgroup of species was sequenced. the results showed that this region was highly conserved in the d. nasuta subgroup. there were only nine variable sites found in this 300-bp-long region, all located in two small regions highly variable among drosophila species. no length variation was observed either within this subgroup or in the yunnan (yn) population of d. albomicans. the deduced ... | 1999 | 10473782 |
| sds-page pattern polymorphism of x-chromosomal glue proteins in natural populations of two drosophila nasuta subgroup species. | for the first time, the glue protein pattern polymorphism in natural populations of d. n. nasuta and d. s. neonasuta has been analyzed by sds-page. the study involving 200 and 185 isofemale lines comprising 2028 and 1900 individuals of d. n. nasuta and d. s. neonasuta, respectively, revealed the occurrence of eight variant glue protein phenotypes in d. n. nasuta and seven in d. s. neonasuta. the number and frequency of variant phenotypes in different populations of both species were found to var ... | 1999 | 10429829 |
| [study on the recognition and evolutionary genetics of the courtship song of species in drosphila nasuta species subgroup]. | the subgroup of drosophila nasuta consists of 14 species, subspecies and taxa. it has a wide distribution in area of indo-pacific ocean. the courtship song of species in nasuta subgroup is recorded for the first time in the paper. some parameters of temporal pattern of pulse song were measured: the inter burst interval (ibi), the interpulse interval (ipi), the length of a pulse train (ptl), the number of pulses in a train (pn), the length of a pulse (pl) and the length of a cycle (cl). computer ... | 1997 | 9414575 |
| the hyperactive x chromosome is not early replicating in mitotically active somatic cells of drosophila nasuta males. | the temporal order of replication of the x chromosome(s) in mitotically dividing male and female cells in early embryos and in brain ganglia of drosophila nasuta larvae was examined using [3h]thymidine pulse labelling and autoradiography. both the x chromosomes in female cells and the single x chromosome in male cells replicated in complete synchrony with the autosome set in the nucleus. thus, unlike the well-known early completion of replication by the hemizygous x chromosome in polytene nuclei ... | 1995 | 7729678 |
| pattern of sexual isolation between parental races (drosophila nasuta nasuta and d.n. albomicans) and the newly evolved races (cytorace i and ii). | d.n. nasuta, d.n. albomicans, cytorace i and cytorace ii [chromosoma, 93 (1986) 243] are closely related strains of the nasuta subgroup. through male choice and female choice experiments, the pattern of sexual isolation if any, among them was analysed. differential mating preference of males and females of these races suggests that they are passing through the process of anagenesis. therefore, this, as an evolutionary experiment under laboratory conditions, offers a rare opportunity to witness d ... | 1994 | 8045622 |
| chromosomal analysis and phylogenetic relationships in the drosophila nasuta subgroup. i. phylogenetic relationships within the drosophila sulfurigaster species complex. | phylogenetic relationships within the drosophila sulfurigaster species-complex, which belongs to the d. nasuta subgroup, were investigated on the basis of chromosomal constitution and morphology. d. pulaua is thought to be the most ancestral species, from which d. s. sulfurigaster and d. s. bilimbata derived in one branch and d. s. albostrigata and d. s. neonasuta in another branch. | 1990 | 2323566 |
| comparative analysis of glue proteins in the drosophila nasuta subgroup. | the patterns of protein fractions from total salivary glands and from glue plugs were compared in seven members of the drosophila nasuta subgroup by the use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). the glue protein patterns are member specific concerning the numbers and the electrophoretic mobilities of major and minor glue protein fractions. however, the major fractions of all subgroup members could be grouped into five sds-page domains according to the homologie ... | 1989 | 2515848 |
| mitochondrial dna evolution in the drosophila nasuta subgroup of species. | the drosophila nasuta group consists of about 12 closely related species distributed throughout the indo-pacific region. they are of great interest because of their evolutionary idiosyncrasies including little morphological differentiation, the ability to intercross in the laboratory often producing fertile offspring, and substantial chromosomal evolution. studies of metric traits, reproductive isolation, and chromosomal and enzyme polymorphisms have failed to resolve the phylogeny of the specie ... | 1989 | 2543832 |
| gene frequencies in natural and laboratory populations of drosophila nasuta. | gene arrangement frequencies of different chromosome types of three inversions, iil-2, iii-35 and iii-2 are reported in some natural and laboratory populations of drosophila nasuta. in general, the frequencies of inversion heterozygotes for these inversions are in excess of what is expected under hardy-weinberg equilibrium in both natural and laboratory populations. this suggests that these inversion heterozygotes are heterotic to the species as far as viability is concerned. similar to what occ ... | 1989 | 2777626 |
| metaphase chromosomes of four species of the drosophila nasuta subgroup. | metaphase chromosomes of four species of the drosophila nasuta subgroup, d. nasuta, d. kepulauana, d. kohkoa, and d. neveifrons, were analysed by the c banding method to clarify the chromosomal differentiation during speciation. four species were different in heterochromatic regions of their chromosomes, especially microchromosomes of the fourth chromosomes and the y chromosomes. intraspecific variations of heterochromatic regions were also found among isofemale lines from various localities of ... | 1988 | 3273767 |
| taxonomic identification of drosophila nasuta subgroup strains by glue protein analysis. | protein fractions of salivary glands were analyzed from 30 wildtype strains of eight species belonging to the drosophila nasuta subgroup by sds-polyacrylamide gel electrophoresis. the electrophoretic patterns indicated several prominent bands which could be shown to represent the major glue protein fractions. the glue protein fractions are species-specific as well as wildtype strain-specific. wildtype strain specificities are characterized by variations of the species-specific patterns. the patt ... | 2017 | 3248713 |
| inversion polymorphism in species of the drosophila nasuta subgroup from thailand. | thailand populations of three species of the d. nasuta complex have been analysed for the presence of paracentric inversions. d. albomicans and d. sulfurigaster albostrigata were collected from phuket, chiang mai and the river kwai, whilst d. kohkoa was found only in phuket and the river kwai. chromosomal polymorphism was studied in respect to geographical distribution. the phuket populations of all three species proved to be highly polymorphic by comparison with the river kwai and chiang mai po ... | 1987 | 3505878 |
| supernumerary chromosomes in drosophila nasuta albomicana. | supernumerary chromosomes have been detected in the karyotype of d.n.albomicana. their number varies from one to three. they are the smallest elements in the karyotype. karyotypes of d.n.albomicana with and without supernumerary chromosomes have been presented. | 1985 | 3996546 |
| a-t specific dna ligands and hypotonic induced supercondensation of chromocentre in brain cells of drosophila nasuta larvae in relation to their synthetic activities. | | 1984 | 6210246 |
| effects of distamycin a & netropsin on condensation of mitotic chromosomes in early embryos & larval brain cells of drosophila nasuta. | | 1983 | 6321337 |
| replication in drosophila chromosomes. x. two kinds of active replicons in salivary gland polytene nuclei and their relation to chromosomal replication patterns. | dna fibre autoradiography of highly polytenized nuclei in salivary glands of drosophila nasuta larvae reveals two distinct types of active replicons. type i replicons are longer (mean size = 64 micrometers), have a very high rate of fork migration (average rate = 0.95 micrometer/min) and generally occur in large arrays often extending over several thousand micrometers. in contrast, the type ii replicons are smaller (mean size = 20 micrometers), slow replicating (average rate = 0.07 micrometer/mi ... | 1983 | 6418475 |
| replication of drosophila chromosomes. ix. stimulation of initiation of polytene replication cycles in vitro by juvenile hormone. | a greater proportion of polytene nuclei show [3h]thymidine incorporation when third instar larval salivary glands of drosophila nasuta are pulse-labelled after in vitro culture (3-24 h) in the presence of a juvenile hormone mimic, zr 515. in glands chronically labelled with [3h]thymidine in the presence of zr 515, more nuclei are seen to have entered new polytene replication cycles. similarly, when salivary glands from larvae fed on 5-fluorodeoxyuridine to block polytene replication cycles at in ... | 1983 | 6218890 |
| further observations on hoechst 33258 plus hypotonic treatment induced supercondensation of interphase heterochromatin in drosophila nasuta cells. | | 1982 | 6188686 |
| satellite dna of drosophila nasuta nasuta and d. n. albomicana: localization in polytene and metaphase chromosomes. | the dna from the two drosophila nasuta races, d. n. nasuta and d. n. albomicana was investigated by cscl density gradient centrifugation. d. n. nasuta has one major at-rich satellite dna sequence with a density of 1.664 g/cm3, while d. n. albomicana has at least three satellites with densities of 1.674 g/cm3, 1.665 g/cm3 and 1.661 g/cm3. the isolated satellite sequences hybridize in situ to all heterochromatic regions of all metaphase chromosomes of both races. in polytene chromosomes the satell ... | 1982 | 7117029 |
| effects of hoechst 33258 on condensation patterns of hetero- and euchromatin in mitotic and interphase nuclei of drosophila nasuta. | | 1981 | 6163649 |
| population genetics of drosophila nasuta nasuta, drosophila nasuta albomicana and their hybrids. vi. pattern of meiotic f1 chromosome segregation. | interracial hybridization experiments between d. n. nasuta and d. n. albomicana were made. during gametogenesis there was selective elimination of abnormal gametes in f1 females; hence, only normal gametes were produced. f1 males yielded both normal and abnormal gametes. fertility tests on f2 and backcross progeny showed males are more often sterile than females. the implications of these findings are discussed. | 2003 | 7204937 |
| replication in drosophila chromosomes: part vi--relative heterochromatin content & autonomous endoreduplication cycles of hetero- & eu-chromatin in brain cells of drosophila nasuta larva. | | 1980 | 7216256 |
| population genetics of drosophila nasuta nasuta, drosophila nasuta albomicana and their hybrids. i. karyotypic mosaicism in the hybrid populations. | d. n. nasuta and d. n. albomicana constitute a pair of chromosomal races with 2n=8 and 2n=6, respectively. the f(1) of these has 2n=7 and it is fertile. there exists a state of karyotypic mosaicism as evidenced by the presence of 26 types of chromosome combinations in f(2), f(3) and f(10) populations. in the midst of this karyotypic noise, the karyotype similar to that of f(1) reached 51% of the population. implications of these findings are discussed. | 1979 | 17248962 |
| a study of heterochromatin in drosophila nasuta by the 5-bromodeoxyuridine-giemsa staining technique. | larval brain ganglia of drosophila nasuta were cultured in vitro in the presence of 5-bromodeoxyuridine for 1 or 5 h at 24 degrees c and the air-dried chromosome preparations stained by the hoechst 33258-giemsa technique to reveal bromodeoxyuridine induced sister chromatid differentiation. in 1 h as well as 5 h preparations, 10-15% of well spread metaphase plates show a sister chromatid differentiation in only c-band heterochromatin regions of different chromosomes. we infer that this sister chr ... | 1979 | 378618 |
| replication in drosophila chromosomes. i. replication of intranucleolar dna in polytene cells of d. nasuta. | the organization and replication of intranucleolar dna in polytene cells of drosophila nasuta have been examined. normal giemsa and fluorescent (hoechst 33258 and quinacrine mustard) staining reveal that in d. nasuta polytene cells, the intranucleolar dna is organized into condensed and disperse forms and very often shows connexion to the alpha heterochromatin of the chromocentre. results of [3h]thymidine autoradiography indicate that the known underreplication of rdna sequences in polytene cell ... | 1979 | 457805 |
| heterochromatin in mitotic chromosomes of drosophila nasuta. | the heterochromatin in mitotic cells of larval neural ganglia of drosophila nasuta has been analysed by c-banding and by fluorescence studies. all chromosomes, except the 'dot'-like 4th chromosome pair, carry large blocks of heterochromatin which are darkly stained by c-banding, and which fluoresce uniformly brightly with hoechst 33258, quinacrine mustard, and acridine orange. these heterochromatic segments make up about 40% of the total metaphase chromosome length. the heterochromatic segments ... | 1978 | 751781 |
| localisation of non-replicating heterochromatin in polytene cells of drosophila nasuta by fluorescence microscopy. | a simple fluorescence technique is decribed to localise in situ the non-replicating alpha heterochromatin in the chromocentre region of drosophila nasuta polytene nuclei. after incorporating 5-bromodeoxyuridine in larval salivary gland cells for one or two cycles of replication, the polytene nuclei are examined for hoechst 33258 flourescence at ph 7.0. the non-replicating alpha heterochromatin remains brightly fluorescing as it does not incorporate any 5-bromodeoxyuridine while the rest of the r ... | 1977 | 65247 |
| reversal of dominance in the competition between drosophila nasuta and drosophila neonasuta. | | 1975 | 1116526 |
| chromosomal polymorphism in drosophila nasuta. iii. inverted gene arrangements in south indian populations. | inversion polymorphism, including a total of 33 inverted gene orders, was studied in south indian populations of d. nasuta nasuta. of these, the x chromosome has one, chromosome 2 has 10, and chromosome 3 has 22 inversions. d. nasuta nasuta has simple, tandem, included, overlapping, and complex types of paracentrics in its polymorphic system. the phylogenetic considerations of these gene orders are discussed. | 2009 | 1151055 |
| developmental studies in drosophila nasuta. 3. developmental obstinacy of the eggs laid after starvation. | | 1974 | 4824617 |
| comparative isozyme patterns in three species of the drosophila nasuta complex. | | 1970 | 5521881 |