Publications

TitleAbstractYear
Filter
PMID
Filter
the influence of amino acid substitutions on the conformational energy of cytochrome c.conformational energies have been evaluated for each of the staggered side-chain conformations associated with the 261 amino acid substitutions known to occur among 60 eucaryotic species. at least 86% of these substitutions can be sterically accommodated (one at a time) within the structure of horse-heart cytochrome c resulting from conformational energy refinement. simultaneous incorporation of all pertinent amino acid substitutions found in eight representative species into the refined horse-h ...1975169879
insect immunity. 11. simultaneous induction of antibacterial activity and selection synthesis of some hemolymph proteins in diapausing pupae of hyalophora cecropia and samia cynthia.we have previously shown that pupae of the giant silkmoth samia cynthia have a humoral antibacterial activity, which was induced by viable, nonpathogenic gram-negative bacteria (h.g. boman et al., 1974). we show here that this activity was formed simultaneously with a selective incorporation of amino acids into eight polypeptide chains characterized by their electrophoretic behavior. if actinomycin d or cycloheximide were given at an early time, no antibacterial activity was found. if the inhibi ...1975812827
insect immunity. i. characteristics of an inducible cell-free antibacterial reaction in hemolymph of samia cynthia pupae.pupae of the silk moth, samia cynthia, were found to contain an inducible antibacterial activity in their hemolymph. this immunity response was provoked by primary infections with either escherichia coli k-12 or enterobacter cloacae. in both cases the antibacterial activity was directed chiefly towards e. coli. during standard conditions, 1% of hemolymph could kill 10(3) to 10(4) viable e. coli, strain d31, within 5 min. a lower level of antibacterial activity was induced by injections of a ster ...19744210336
inactivation of alpha-ecdysone and cyasterone by larvae of the fleshfly, sarcophaga peregrina, and pupae of the silkworm, samia cynthia. 19705433302
the prothoracicotropic hormone bombyxin has specific receptors on insect ovarian cells.bombyxin ii, a product of the brain of the adult silkmoth, bombyx mori, binds to ovarian cells of three different species of lepidoptera, i.e. b. mori (silkmoth), samia cynthia ricini (ailanthus moth), and an ovarian cell line of spodoptera frugiperda (sf9) (fall armyworm). crude sf9 cell membrane preparations were used to show that the purported bombyxin receptor binds its ligand in a specific, saturable, and reversible manner. the dissociation constant of the bombyxin-receptor complex is 260+/ ...19979183018
bombyxin: an insect neurohormone targets the ovaries in lepidoptera.bombyxin, an insect hormone structurally related to insulin, was chemically synthesized and defined radioactively labeled probes were generated in order to detect and characterize bombyxin receptors in insect tissue. in all species tested, bombyx mori (silkmoth), samia cynthia ricini (ailanthus moth). manduca sexta (tobacco hornworm) and spodoptera frugiperda (fall armyworm), bombyxin receptors were found in ovaries. a radioactive photolabeled bombyxin analog was crosslinked to the potential bom ...19979274060
protein purification, cdna cloning and gene expression of lysozyme from eri-silkworm, samia cynthia ricini.lysozyme was isolated from immunized hemolymph of samia cynthia ricini larvae by heat treatment, cation exchange and reverse-phase chromatography. a cdna encoding lysozyme was cloned by screening the cdna library from immunized fat body using, as a probe, a dna fragment obtained by pcr-based differential display method. the deduced amino acid sequence showed high homology with other chicken-type lysozymes. the calculated molecular mass of the mature peptide was 13785, which agreed precisely with ...200111290453
comparison of leaf life span, photosynthesis and defensive traits across seven species of deciduous broad-leaf tree seedlings.leaf life span, photosynthetic parameters and defensive traits were compared across seven species of deciduous broad-leaved tree seedlings native to northern japan to test the "cost-benefit hypothesis" that more productive leaves are more susceptible to herbivore attack than less productive leaves.200616510512
cloning and expression of a gene encoding gallerimycin, a cysteine-rich antifungal peptide, from eri-silkworm, samia cynthia ricini.a cdna clone encoding gallerimycin was isolated from larval fat body of immunized samia cynthia ricini and named as scr-gallerimycin. in naive larvae, no gene expression was detected, but strongly induced in fat body and hemocytes following immune challenge with bacteria or entomopathogenic fungus beauveria bassiana. strong expression of the gene was also induced by injection of peptidoglycan and zymosan, but very weakly by non-pathogenic fungus aspergillus oryzae. analysis of the sequence upstr ...200818436462
bombyxin: an insect brain peptide that belongs to the insulin family.bombyxin is a 5 kda secretory brain peptide that belongs to the insulin family. bombyxin of the silkmoth bombyx mori can induce adult development when injected into brain-removed dormant pupae of the saturniid moth samia cynthia ricini by activating the prothoracic glands to synthesize and release ecdysone. bombyx bombyxin has been shown to lower the concentration of the major haemolymph sugar, trehalose, and to elevate the trehalase activity in the midgut and muscles in bombyx, but the doses re ...200018522456
samia cynthia versus bombyx mori: comparative gene mapping between a species with a low-number karyotype and the model species of lepidoptera.we performed gene-based comparative fish mapping between a wild silkmoth, samia cynthia ssp. with a low number of chromosomes (2n=25-28) and the model species, bombyx mori (2n=56), in order to identify the genomic components that make up the chromosomes in a low-number karyotype. mapping of 64 fosmid probes containing orthologs of b. mori genes revealed that the homologues of either two or four b. mori chromosomes constitute the s. c. ricini (vietnam population, 2n=27ôöç/28ôöé, z0/zz) autosomes. ...201121396446
development of a multiplex polymerase chain reaction for the simultaneous detection of microsporidians, nucleopolyhedrovirus, and densovirus infecting silkworms.we have developed a novel pcr-based assay for individual and simultaneous detection of three major pathogens (microsporidians, nucleopolyhedrovirus (npv) and densovirus (dnv)) infecting the silkworm, bombyx mori. multiplex pcr, using three primer pairs, two of which were designed from the conserved regions of 16s small subunit ribosomal rna gene of microsporidians, and polyhedrin gene of npvs respectively, and a third primer pair designed from the internal sequences of b. mori dnvs (bmdnv), show ...201121570404
histology, secretory activity and metamorphic changes in the ventral nerve cord neurosecretory cells in the larvae of samia cynthia ricini (lepidoptera: saturnidae). 20143993178
histology and secretory activity of cephalic neurosecretory cells in adult samia cynthia ricini (lepidoptera: saturnidae). 20143993177
insect antimicrobial peptides and their applications.insects are one of the major sources of antimicrobial peptides/proteins (amps). since observation of antimicrobial activity in the hemolymph of pupae from the giant silk moths samia cynthia and hyalophora cecropia in 1974 and purification of first insect amp (cecropin) from h. cecropia pupae in 1980, over 150 insect amps have been purified or identified. most insect amps are small and cationic, and they show activities against bacteria and/or fungi, as well as some parasites and viruses. insect ...201424811407
genetic analysis of scattered populations of the indian eri silkworm, samia cynthia ricini donovan: differentiation of subpopulations.deforestation and exploitation has led to the fragmentation of habitats and scattering of populations of the economically important eri silkworm, samia cynthia ricini, in north-east india. genetic analysis of 15 eri populations, using issr markers, showed 98% inter-population, and 23% to 58% intra-population polymorphism. nei's genetic distance between populations increased significantly with altitude (r(2) = 0.71) and geographic distance (r(2) = 0.78). on the dendrogram, the lower and upper ass ...201121931526
wildsilkbase: an est database of wild silkmoths.functional genomics has particular promise in silkworm biology for identifying genes involved in a variety of biological functions that include: synthesis and secretion of silk, sex determination pathways, insect-pathogen interactions, chorionogenesis, molecular clocks. wild silkmoths have hardly been the subject of detailed scientific investigations, owing largely to non-availability of molecular and genetic data on these species. as a first step, in the present study we generated large scale e ...200818637161
expression and purification of virus like particles (vlps) of foot-and-mouth disease virus in eri silkworm (samia cynthia ricini) larvae.foot-and-mouth disease (fmd) is a highly contagious viral disease, which causes severe economic loss to livestock. virus like particles (vlps) produced by recombinant dna technology are gaining importance because of their immunogenic properties and safety in developing a new vaccine for fmd. in the present study, a practical and economically feasible approach of expression, purification and characterization of vlps of fmdv in eri silkworm (samia cynthia ricini) larvae was described. although thr ...201626925448
amino acid sequence of a prothoracicotropic hormone of the silkworm bombyx mori.we have determined the complete amino acid sequence of 4k-ptth-ii, one of three forms of the m(r) 4400 prothoracicotropic hormone of the silkworm bombyx mori, active to brainless pupae of samia cynthia ricini. like vertebrate insulin, it consists of two nonidentical peptide chains (a and b chains). the a chain consists of 20 amino acid residues. the b chain is a mixture of four microheterogeneous peptides, two of which consist of 28 residues, and the other two, of 26 residues. 4k-ptth-ii has con ...198616593744
pharmacological study on samia cynthia ricini in old female mice.the effect of the extraction from female moths samia cynthia ricini (family saturniidae) on menopausal syndrome was studied in order to search for an effective traditional chinese medicine to menopausal syndrome and offer a theoretical support for the further research on samia cynthia ricini. aged, nonreproductive female mice was used as the model and randomly divided into three groups: control, ethanol extraction group and diethylstilbestrol (des) group according to the medicine applied. after ...200616325359
a cytoplasmic xylanase (xynx) of aeromonas caviae me-1 is released from the cytoplasm to the periplasm by osmotic downshock.aeromonas caviae me-1 is a multiple xylanase-producing gram-negative bacterium which was isolated from the gut contents of a wild silkworm, samia cynthia pryeri. one of the xylanases produced by a. caviae me-1, xynx (38 kda, family 10 xylanase), hydrolyzes xylan to xylobiose and xylotetraose as final degradation products. generally, xylanases are extracellular or cell surface enzymes. however, xynx is not exported to the extracellular fluid by a. caviae me-1 and an escherichia coli transformant ...200316233445
molecular characterization of prothoracicotropic hormone (ptth) from the giant silkmoth antheraea pernyi: developmental appearance of ptth-expressing cells and relationship to circadian clock cells in central brain.using a pcr strategy, we have cloned the cdna for prothoracicotropic hormone (ptth) from the giant silkmoth, antheraea pernyi. the a. pernyi ptth cdna encodes a preprohormone of 221 amino acids that is 51 and 71% identical at the amino acid level with bombyx mori and samia cynthia ricini ptths, respectively. bacterially expressed, recombinant a. pernyi ptth stimulates adult development when injected into debrained pupae. ptth protein (ca. 30 kda by western blot) and mrna (ca. 0.9 kb by northern ...19968812139
the cdna-structure of the prothoracicotropic hormone (ptth) of the silkmoth hyalophora cecropia.the structure of the prothoracicotropic neurohormone (ptth) of the silkmoth hyalophora cecropia was elucidated at the cdna level. the identified cdna of 803 nt, which is over 90% identical with the corresponding part of the samia cynthia ricini ptth gene, encodes a preprohormone of 240 amino acids. presence of proteolytic cleavage sites indicates that the preprohormone is split into a signal peptide, an intercalated peptide (64 residues), and the ptth monomer (125 residues). preprohormones of h. ...200211755069
uptake of atmospheric carbon dioxide into silk fiber by silkworms.the relation between the uptake of atmospheric co(2) and insect's production of silk fiber has not yet been reported. here, we provide the first quantitative demonstrations that four species of silkworms (bombyx mori, samia cynthia ricini, antheraea pernyi, and antheraea yamamai) and a silk-producing spider (nephila clavata) incorporate atmospheric co(2) into their silk fibers. the abundance of (13)c incorporated from the environment was determined by mass spectrometry and (13)c nmr measurements ...201312741798
toxicity of bacillus thuringiensis crystal proteins against eri silkworm, samia cynthia ricini (lepidoptera: saturniidae).ten purified crystal proteins of bacillus thuringiensis (bt) were tested at concentrations ranging from 2.93 to 3000ng/cm(2) for their toxicity to eri silkworm through protein paint bioassays using castor leaves. based on lc50 values, cry1aa (2.6ng/cm(2)) was highly toxic followed by cry1ac (29.3ng/cm(2)) and cry1ab (68.7ng/cm(2)). the cry1ca and cry1ea proteins were moderately toxic to eri silkworm larvae and resulted in 23% and 28% mortality, respectively at the highest concentration tested (3 ...201627377590
comparative genetic diversity and genetic structure of three chinese silkworm species bombyx mori l. (lepidoptera: bombycidae), antheraea pernyi guérin-meneville and samia cynthia ricini donovan (lepidoptera: saturniidae).the genetic diversity and genetic structure of three chinese silkworm species bombyx mori l., antheraea pernyi guérin-meneville and samia cynthia ricini donovan were comparatively assessed based on rapd markers. at the species level, a. pernyi and b. mori showed high levels of genetic diversity, whereas s. cynthia ricini showed low level of genetic diversity. however, at the strain level, a. pernyi had relatively highest genetic diversity and b. mori had lowest genetic diversity. analysis of mol ...201121271066
rheological properties of native silk fibroins from domestic and wild silkworms, and flow analysis in each spinneret by a finite element method.silkworms can produce strong and tough fibers at room temperature and from an aqueous solution. therefore, it seems useful to study the mechanism of fiber formation by silkworms for development of synthetic polymers with excellent mechanical properties. the rheological behaviors of native silk dopes stored in the silk glands of bombyx mori and samia cynthia ricini were clarified, and flow simulations of the dopes in each spinneret were performed with a finite element method. dynamic viscoelastic ...200919317399
involvement of tyrosine residues in the tanning of proteins by 3-hydroxyanthranilic acid.the binding of oxidized phenolic compounds to proteins is of importance in a number of biological systems, including the sclerotization of insect cuticle and the tanning of cocoons. 3-hydroxyanthranilic acid (3haa), an aminophenol, is a tryptophan metabolite that undergoes autoxidation readily, and proteins incubated in the presence of 3haa and oxygen become colored and oxidized. some moth species are thought to employ this reactivity of 3haa with proteins for the tanning of cocoons, but the det ...199211607283
an evaluation of 1-deoxynojirimycin oral administration in eri silkworm through fat body metabolomics based on (1) h nuclear magnetic resonance.1-deoxynojirimycin (dnj), the main hypoglycemic constituent in mulberry (morus alba) latex, has been extensively researched. although there is considerable interest in the biological effects of dnj, the roles of 1-deoxynojirimycin (dnj) in glycometabolism and energy metabolism in insects have received little attention. in this paper, (1)h nuclear magnetic resonance ((1)h nmr) based metabonomic was performed to study the effects of the oral supplementation of 0.25% dnj, 0.5% dnj, latex, and the m ...201627294120
metabolic changes in the midgut of eri silkworm after oral administration of 1-deoxynojirimycin: a 1h-nmr-based metabonomic study.1-deoxynojirimycin (dnj) is a natural d-glucose analogue and has a strong physiological activity in inhibiting α-glucosidase in vivo. the antidiabetic effects of dnj in mice or other mammals were extensively explored, but the physiological and toxic roles of dnj in insects was seldom reported. in this study, the biological effects of dnj were examined in midgut extracts of fourth-instar larvae of eri silkworm (samia cynthia ricini, saturniidae). based on nuclear magnetic resonance (nmr) metabono ...201728249023
genetic evaluation of eri silkworm samia cynthia ricini: issr loci specific to high and low altitude regimes and quantitative attributes.genetic structure of populations is under constant pressure from varying geographical conditions that induce phenotypic plasticity in insects. spatial distribution of 15 populations of indian eri silkworm, samia cynthia ricini originated at various altitudes of sub himalayas based on euclidean distance realized from yield attributes showed two population clusters irrespective of their place of origin and altitude. however, dna amplification profile by inter ssr (issr) markers showed genetic vari ...201121559996
evaluation of the properties of silk fibroin films from the non-mulberry silkworm samia cynthia ricini for biomaterial design.silk fibroin from a domesticated mulberry silkworm, bombyx mori, is the most widely used in biomaterial design. we report for the first time the preparation of a relatively smooth (granule free) film of the nonmulberry samia cynthia ricini fibroin for comparative evaluation of its cell-supporting properties against those of the b. mori fibroin film. the granule formation on the s. c. ricini fibroin film was successfully prevented by facilitating proper rearrangement of the protein molecules, as ...201121029516
step-by-step evolution of neo-sex chromosomes in geographical populations of wild silkmoths, samia cynthia ssp.geographical subspecies of wild silkmoths, samia cynthia ssp. (lepidoptera: saturniidae), differ considerably in sex chromosome constitution owing to sex chromosome fusions with autosomes, which leads to variation in chromosome numbers. we cloned s. cynthia orthologues of 16 bombyx mori genes and mapped them to chromosome spreads of s. cynthia subspecies by fluorescence in situ hybridization (fish) to determine the origin of s. cynthia neo-sex chromosomes. fish mapping revealed that the z chromo ...201120668432
identification and characterization of globin genes from two lepidopteran insects, bombyx mori and samia cynthia ricini.we describe the characterization of hemoglobin-like genes from two lepidopteran insects, bombyx mori (bmglobin) and samia cynthia ricini (scglobin). bmglobin and scglobin are predicted to be intracellular proteins and contain amino acids required for heme and oxygen binding. expression profiles of two lepidopteran globins, especially bmglobin, were different from that of other insect globins. although other insect globins are mainly associated with the tracheal system, bmglobin was expressed alm ...200919059317
[research for the production of recombinant human epidermal growth factor using samia cynthia ricini pupae bioreactor].the protein production system using a baculovirus antheraea pernyi nucleopolyhedrovirus (anpenpv) as a gene expression vector and its host insect as a natural bioreactor was successful established and its excellent performance in the protein production has been demonstrated. in this paper, the system is used to produce recombinant human epidermal growth factor (rhegf), which have been widely used in medical and cosmetic treatment. a recombinant anpehegf virus has been constructed by replacing th ...201323488154
design, expression and solid-state nmr characterization of silk-like materials constructed from sequences of spider silk, samia cynthia ricini and bombyx mori silk fibroins.silk has a long history of use in medicine as sutures. to address the requirements of a mechanically robust and biocompatible material, basic research to clarify the role of repeated sequences in silk fibroin in its structures and properties seems important as well as the development of a processing technique suitable for the preparation of fibers with excellent mechanical properties. in this study, three silk-like protein analogs were constructed from two regions selected from among the crystal ...200516002994
microscopic structural analysis of fractured silk fibers from bombyx mori and samia cynthia ricini using 13c cp/mas nmr with a 1mm microcoil mas nmr probehead.conformational changes have been studied in silk fibers from the domestic silkworm bombyx mori and a wild silkworm samia cynthia ricini as a result of fractured by stretching. about 300 samples consisting of only the fractured regions of [1-13c]ala or [1-13c]gly labeled silk fibers were collected and observed by 13c cp/mas nmr spectra. the total amount of these fractured fibers is only about 1mg and therefore we used a home-built 1mm microcoil mas nmr probehead. a very small increase in the frac ...201020579856
pest management through bacillus thuringiensis (bt) in a tea-silkworm ecosystem: status and potential prospects.bacillus thuringiensis (bt) is a soil bacterium that forms spores containing crystals comprising one or more cry or cyt proteins having potential and specific insecticidal activity. different strains of bt produce different types of toxins, affecting a narrow taxonomic group of insects. therefore, it is used in non-chemical pest management, including inherent pest resistance through gm crops. the specificity of action of bt toxins reduces the concern of adverse effects on non-target species, a c ...201728144706
distinctive presence of peritracheal athrocytes in bombyx mori l. and bombyx mandarina m. as compared to their absence in several other lepidopteran species.pericardial cells are present in a wide variety of insects and are thought to constitute the majority of 'athrocytes (nephrocytes)'. in contrast, peritracheal athrocytes have only been observed in bombyx mori l. although peritracheal athrocytes have a distinct morphology, it is unknown whether these cells are common to all lepidopterans. we anatomically compared eight lepidopteran species: bombyx mori l. and bombyx mandarina m. (bombycidae); samia cynthia ricini d. (saturniidae); agrius convolvu ...200618089062
prominent down-regulation of storage protein genes after bacterial challenge in eri-silkworm, samia cynthia ricini.we constructed two independent cdna libraries from the fat body of escherichia coli- or candida albicans-challenged eri-silkworm samia cynthia ricini larvae. we performed comparative expressed sequence tag (est) analysis of the two cdna libraries and found that two putative storage protein genes, scsp1 and scsp2, were markedly repressed by e. coli injection as compared with c. albicans injection. by quantitative real-time rt-pcr analysis, we showed that scsp1 mrna significantly reduced to 1/32-1 ...200818064702
peptidoglycan recognition protein (pgrp) from eri-silkworm, samia cynthia ricini; protein purification and induction of the gene expression.peptidoglycan recognition protein (pgrp) was isolated from immunized hemolymph of the wild silkworm, samia cynthia ricini, detecting the biding activity with (125)i-labeled peptidoglycan (pgn). the binding specificity of pgrp was tested by competitive inhibition of the binding to (125)i-labeled-pgn by a large excess amount of non-labeled-pgn or other glucans. the binding to labeled uncross-linked lys-type pgn from micrococcus luteus was strongly inhibited by non-labeled-pgn of the same structure ...200717434328
beta-1,3-glucan inducible expression of prophenoloxidase-activating proteinase from eri-silkworm, samia cynthia ricini.a cdna clone encoding possible prophenoloxidase-activating serine protease (pap) was isolated by screening the cdna library from immunized larval fat body of the wild silkmoth, samia cynthia ricini. the cdna encodes a 438 amino acid open reading frame with a predicted 20 residue signal peptide. samia pap has high sequence similarity to bombyx mori and manduca sexta paps, which contain two amino terminal clip domains followed by a carboxyl-terminal catalytic domain. the expression of the gene was ...200717307003
biochemical and molecular characterization of allatotropin and allatostatin from the eri silkworm, samia cynthia ricini.in a previous study, allatotropic and allatostatic activities were observed in brain extract from the eri silkworm, samia cynthia ricini (samcri) [li, s., jiang, r.-j., cao, m.-x., 2002b. allatotropic and allatostatic activities in brain extracts of the eri silkworm, s. cynthia ricini, and the effects of manduca sexta allatotropin and m. sexta allatostatin on juvenile hormone in vitro. physiol. entomol. 27, 322-329]. in the present study, the hplc purified samcri-allatotropin (at) and -allatosta ...200717175449
a novel sucrose hydrolase from the bombycoid silkworms bombyx mori, trilocha varians, and samia cynthia ricini with a substrate specificity for sucrose.although membrane-associated sucrase activity has been detected in the midgut of various lepidopteran species, it has not yet been identified and characterized at the molecular level. in the present study, we identified a novel sucrose hydrolase (suh) gene from the following three bombycoid silkworms: bombyx mori, trilocha varians, and samia cynthia ricini and named them bmsuh, tvsuh, and scsuh, respectively. the est dataset showed that bmsuh is one of the major glycoside hydrolase genes in the ...201525937576
molecular characterization and expression of prothoracicotropic hormone during development and pupal diapause in the cotton bollworm, helicoverpa armigera.using a strategy of rapid amplification of cdna ends, the cdna encoding prothoracicotropic hormone (ptth) was cloned from the brain of helicoverpa armigera (hearm). the hearm-ptth cdna contains an open reading frame encoding a 226-amino acid preprohormone, which shows high identity with the closely related noctuid moths, helicoverpa zea (98%) and heliothis virescens (94%), and low identity with five species of bombycoidea: bombyx mori (57%), manduca sexta (55%), hyalophora cecropia (52%), samia ...200515869761
cdna cloning and expression of bacteria-induced hdd11 gene from eri-silkworm, samia cynthia ricini.a cdna clone encoding hdd11 protein, a bacteria-induced protein of unknown function, was isolated from fat body of immunized samia cynthia ricini larvae based on suppression subtractive hybridization. the cdna encodes a 167 amino acid residue open reading frame with an 18 residue predicted signal peptide. the deduced amino acid sequence showed 54% and 55% identity with hdd11 proteins from hyphantria cunea and manduca sexta, respectively. expression of the gene was undetectable in naive larvae wh ...200315012905
production and characterization of a silk-like hybrid protein, based on the polyalanine region of samia cynthia ricini silk fibroin and a cell adhesive region derived from fibronectin.there are a variety of silkworms and silk fibroins produced by them. silks have many inherent suitable properties for biomaterials. in this paper, a novel silk-like hybrid protein, [dgg(a)(12)ggaastgrgdspaas](5), which consists of polyalanine region of silk fibroin from a wild silkworm, samia cynthia ricini, and cell adhesive region including arg-gly-asp (rgd) sequence, derived from fibronectin, was designed and produced. the genes encoding the hybrid protein were constructed and expressed in es ...200414607499
molecular cloning of the prothoracicotropic hormone from the tobacco hornworm, manduca sexta.a cdna encoding a putative precursor of prothoracicotropic hormone (ptth) from the tobacco hornworm, manduca sexta, was isolated and sequenced. this clone contains an open reading frame encoding a 226-amino acid prepropeptide hormone. the deduced amino acid sequence is composed of a signal sequence, a precursor domain and a mature hormone and shows similarities to the other ptths that have been cloned from closely related lepidopteran species, bombyx mori, samia cynthia ricini, antheraea peryni, ...200312878226
juvenile hormone acid methyl transferase is a key regulatory enzyme for juvenile hormone synthesis in the eri silkworm, samia cynthica ricini.during the period of adult emergence in the eri silkworm, samia cynthia ricini, the corpora allata (ca) are apparently reactivated in females, but not males. this creates a significant sexual dimorphism in juvenile hormone (jh) synthesis by ca. to determine the underlying molecular mechanisms in this process, we cloned cdnas of two enzymes involved in the jh synthesis pathway: 3-hydroxy-3-methylglutaryl coa reductase (hmgr) and juvenile hormone acid methyl transferase (jhamt). both samcri-hmgr a ...200818839418
the fate of w chromosomes in hybrids between wild silkmoths, samia cynthia ssp.: no role in sex determination and reproduction.moths and butterflies (lepidoptera) have sex chromosome systems with female heterogamety (wz/zz or derived variants). the maternally inherited w chromosome is known to determine female sex in the silkworm, bombyx mori. however, little is known about the role of w chromosome in other lepidopteran species. here we describe two forms of the w chromosome, w and neo-w, that are transmitted to both sexes in offspring of hybrids from reciprocal crosses between subspecies of wild silkmoths, samia cynthi ...201626758188
a 1h-nmr based study on hemolymph metabolomics in eri silkworm after oral administration of 1-deoxynojirimycin.we aimed to investigate whether 1-deoxynojirimycin (dnj) modulates glycometabolism and has toxicity in eri silkworm (samia cynthia ricini, saturniidae). in this paper, hemolymph metabolites were used to explore metabolic changes after oral administration of dnj or mulberry latex and to characterize the biological function of dnj at the metabolic and systemic levels. hemolymph samples were collected from fourth-instar larvae of eri silkworm and ex-vivo high-resolution 1h nuclear magnetic resonanc ...201526148185
synthesis and characterization of chimeric silkworm silk.a synthetic gene encoding a chimeric silklike protein was constructed that combined a polyalanine encoding region (ala)(18), a sequence slightly longer than the (ala)(12-13) found in the silk fibroin from the wild silkworm samia cynthia ricini, and a sequence encoding gvgagygagagygvgagygagvgygagagy, found in the silk fibroin from the silkworm bombyx mori. a tetramer of the chimeric repeat sequence encoding a approximately 29 kda protein was expressed as a fusion protein in escherichia coli. in c ...200312741803
protein purification, cdna cloning and gene expression of attacin, an antibacterial protein, from eri-silkworm, samia cynthia ricini.attacin was isolated from immunized larval hemolymph of the wild silkmoth, samia cynthia ricini. the antibacterial effect of the attacin was limited to some species of gram-negative bacteria. two cdna clones encoding attacin a and b, respectively, were isolated by screening the cdna library from immunized fat body. the two cdnas encoded the same length of precursor protein with 233 amino acid residues. the 46-residue prepropeptides of the two attacins were identical to each other, but 4 out of 1 ...200212110295
induction of tyrosine hydroxylase gene expression by bacteria in the fat body of eri-silkworm, samia cynthia ricini.a cdna clone encoding tyrosine hydroxylase (th) was isolated from larval fat body of immunized samia cynthia ricini. in naive larvae, the th gene was expressed only in the brain, but strongly induced in fat body and hemocytes after injecting uv-killed bacteria. the induction of the gene was rather short-lived compared to that of antibacterial protein genes, reaching the maximum levels 6h after bacterial challenge, and then quickly diminished. a strong induction of the gene expression was caused ...200818178496
three peptidoglycan recognition protein (pgrp) genes encoding potential amidase from eri-silkworm, samia cynthia ricini.three cdna clones encoding peptidoglycan recognition proteins (pgrp-b, -c and -d) were isolated from larval fat body of immunized samia cynthia ricini. the deduced amino acid sequences show high homology to each other and also to drosophila pgrp-lb, but rather lower homology to all of the known lepidopteran pgrps including samia pgrp-a, a receptor-type pgrp. the three pgrps conserve the five amino acid residues which form the catalytic site of n-acetylmuramoyl l-alanine amidase as in drosophila ...200717689997
protein secondary structure and orientation in silk as revealed by raman spectromicroscopy.taking advantage of recent advances in polarized raman microspectroscopy, and based on a rational decomposition of the amide i band, the conformation and orientation of proteins have been determined for cocoon silks of the silkworms bombyx mori and samia cynthia ricini and dragline silks of the spiders nephila clavipes and nephila edulis. this study distinguished between band components due to beta-sheets, beta-turns, 3(1)-helices, and unordered structure for the four fibers. for b. mori, the be ...200717277183
induction of hemolin gene expression by bacterial cell wall components in eri-silkworm, samia cynthia ricini.a cdna clone encoding hemolin was isolated from fat body of immunized samia cynthia ricini larvae based on subtractive suppression hybridization method. the cdna encodes 413 amino acid residue open reading frame with an 18 residue predicted signal peptide. the expression of the gene was strongly induced in fat body and midgut by an injection of bacterial cells or peptidoglycans, but very weakly by lipopolysaccharide. the mrna expression in the fat body was detected as early as 3 h post-injection ...200717126583
characterization by raman microspectroscopy of the strain-induced conformational transition in fibroin fibers from the silkworm samia cynthia ricini.raman microspectroscopy has been used to quantitatively study the effect of a mechanical deformation on the conformation and orientation of samia cynthia ricini (s. c. ricini) silk fibroin. samples were obtained from the aqueous solution stored in the silk gland and stretched at draw ratios (lambda) ranging from 0 to 11. using an appropriate band decomposition procedure, polarized and orientation-insensitive spectra have been analyzed to determine order parameters and the content of secondary st ...200616961312
structural analysis of alanine tripeptide with antiparallel and parallel beta-sheet structures in relation to the analysis of mixed beta-sheet structures in samia cynthia ricini silk protein fiber using solid-state nmr spectroscopy.the structural analysis of natural protein fibers with mixed parallel and antiparallel beta-sheet structures by solid-state nmr is reported. to obtain nmr parameters that can characterize these beta-sheet structures, (13)c solid-state nmr experiments were performed on two alanine tripeptide samples: one with 100% parallel beta-sheet structure and the other with 100% antiparallel beta-sheet structure. all (13)c resonances of the tripeptides could be assigned by a comparison of the methyl (13)c re ...200616669693
isolation and characterization of neutral lipids of desilked eri silkworm pupae grown on castor and tapioca leaves.the neutral lipid of desilked eri silkworm pupae (samia cynthia ricini) grown on two different host plants, castor (ricinus communis linn.) and tapioca (manihot utilizsima phol.) leaves, was extracted with hexane. the oil content in pupae was estimated to be in the range of 18-20% (dry basis). the pupal oil was found to be enriched with alpha-linolenic acid (ala) with palmitic acid as the second major fatty acid. the level of ala in the oil of silkworm pupae was found to be significantly higher ...200616637689
comparison of sequences of a transcriptional coactivator mbf2 from three lepidopteran species bombyx mori, bombyx mandarina and samia cynthia.mbf2 was first isolated from the silkworm bombyx mori as a positive cofactor that activates transcription through its interaction with tfiia. to identify conserved domain(s) within the mbf2 molecule, we isolated cdnas encoding mbf2 homologues from other silkworms bombyx mandarina and samia cynthia. bacterially expressed and purified mbf2 of b. mandarina and s. cynthia activated transcription in vitro. the predicted amino acid sequences of mbf2 from two bombyx species share 97% homology. when we ...19989767108
purification and characterization of two insecticyanin-type proteins from the larval hemolymph of the eri-silkworm, samia cynthia ricini.two different biliverdin-binding proteins, designated bbp-i and bbp-ii, were purified from the larval hemolymph of the eri-silkworm, samia cynthia ricini. these proteins were readily isolated from the hemolymph of fifth instar larvae using two chromatographic steps, hydrophobic interaction chromatography and ion exchange chromatography. both bbps were easily separated by q-sepharose hp column chromatography. bbp-i has an apparent molecular weight of 24 kda, as determined by gel-filtration and so ...19989545563
the brain secretory peptides that control moulting and metamorphosis of the silkmoth, bombyx mori.progress made toward the elucidation of molecular features of the prothoracicotropic hormone (ptth) of the silkmoth bombyx mori is reviewed. ptth stimulates the prothoracic glands to synthesize and release ecdysone, and is therefore a key hormone for the regulation of insect moulting and metamorphosis. bombyx ptth is a 30 kda homodimeric glycoprotein, whose carbohydrate moiety is not essential for the biological function. the bombyx genome contains a single copy of the ptth gene. ptth is produce ...19947981038
structure and expression of bombyxin-related peptide genes of the moth samia cynthia ricini.from the genomic dna of the moth samia cynthia ricini, we cloned and characterized six clustered genes that encode precursor molecules for peptides structurally related to bombyxin, a bombyx mori brain secretory peptide that is structurally like insulin and functionally like the prothoracicotropic hormone. the precursor molecules deduced from these genes have the domain organization of signal peptide/b-chain/c-peptide/a-chain, as in preprobombyxins and preproinsulins. the samia bombyxin-related ...19921601275
a monoclonal antibody against a synthetic fragment of bombyxin (4k-prothoracicotropic hormone) from the silkmoth, bombyx mori: characterization and immunohistochemistry.monoclonal antibodies were produced by immunizing mice with a synthetic decapeptide corresponding to the n-terminal portion of the a-chain of bombyxin, a peptide from bombyx mori which activates the prothoracic glands of the saturniid moth, samia cynthia ricini, and was previously called 4k-ptth. we obtained a hybridoma clone secreting an antibody that recognized specifically bombyxin after treatments for disulfide-bond reduction but did not when untreated. immunoblotting studies demonstrated th ...19873297849
isolation and some characterization of the prothoracicotropic hormone from bombyx mori.the prothoracicotropic hormone (ptth) was isolated from adult heads of bombyx mori. fifty micrograms of pure ptth was obtained from 648,000 heads through a 15-step purification procedure with a 2 x 10(6)-fold purification and an 8% recovery. chemical analyses of this ptth have shown that it is a single-chain peptide consisting of 40-43 amino acid residues (mw, 4330-4740), the n-terminus of which is glycine. as little as 0.1 ng of ptth elicited adult development in a debrained pupa of samia cynth ...19846714648
genetic diversity and differentiation among populations of the indian eri silkworm, samia cynthia ricini, revealed by issr markers.samia cynthia ricini (lepidoptera: saturniidae), the indian eri silkworm, contributes significantly to the production of commercial silk and is widely distributed in the brahmaputra river valley in north-eastern india. due to over exploitation coupled with rapid deforestation, most of the natural populations of s. cynthia ricini are dwindling rapidly and its preservation has become an important goal. assessment of the genetic structure of each population is a prerequisite for a sustainable conse ...200619537974
structure of model peptides based on nephila clavipes dragline silk spidroin (masp1) studied by 13c cross polarization/magic angle spinning nmr.to obtain detailed structural information for spider dragline spidroin (masp1), we prepared three versions of the consensus peptide gglggqgagaaaaaaggagqggygglgsqgagr labeled with 13c at six different sites. the 13c cp/mas nmr spectra were observed after treating the peptides with different reagents known to alter silk protein conformations. the conformation-dependent 13c nmr chemical shifts and peak deconvolution were used to determine the local structure and the fractional compositions of the c ...201316283749
a doqsy approach for the elucidation of torsion angle distributions in biopolymers: application to silk.silk from the wild silkworm samia cynthia ricini with a molecular mass of about 300kda consists of alternating repeats of nano-crystalline poly-(ala) and non-crystalline glycine-rich domains. the backbone torsion angles between pairs of these two amino acids is determined by doqsy solid-state nmr spectroscopy: the alanine-rich domains are predominantly in a beta-sheet conformation, whereas the glycine-rich domains are found to be partially in an extended beta-sheet conformation and partially in ...200616243550
a novel lebocin-like gene from eri-silkworm, samia cynthia ricini, that does not encode the antibacterial peptide lebocin.a cdna clone with homology to lebocin gene was isolated from fat body of immunized samia cynthia ricini larvae. the cdna has an open reading frame encoding 162 amino acid residues. the deduced amino acid sequence shows significant homology to lebocin precursor proteins from bombyx mori and trichoplusia ni only in the "prosegment" region, but no homology to mature lebocin, a proline-rich antibacterial peptide, indicating the protein is not a precursor for lebocin antibacterial peptide. northern a ...200515621517
study of protein conformation and orientation in silkworm and spider silk fibers using raman microspectroscopy.raman microspectroscopy has been used for the first time to determine quantitatively the orientation of the beta-sheets in silk monofilaments from bombyx mori and samia cynthia ricini silkworms, and from the spider nephila edulis. it is shown that, for systems with uniaxial symmetry such as silk, it is possible to determine the order parameters p2 and p4 of the orientation distribution function from intensity ratios of polarized raman spectra. the equations allowing the calculation of p2 and p4 ...201315530039
structure and structural changes of the silk fibroin from samia cynthia ricini using nuclear magnetic resonance spectroscopy.the structure of silk fibroin from a wild silkworm, s. c. ricini, the amino acid sequence of which consists of repeated poly-ala and gly-rich regions, was examined by using solution and solid-state nmr methods. the structural transition of the silk fibroin in aqueous solution was monitored by using 13c solution nmr spectroscopy as a function of temperature. the fast exchange with respect to the chemical shift between the helix and coil conformations was observed in the poly-ala region and the sl ...200415468207
structures of bombyx mori and samia cynthia ricini silk fibroins studied with solid-state nmr.there are many kinds of silks spun by silkworms and spiders, which are suitable to study the structure-property relationship for molecular design of fibers with high strength and high elasticity. in this review, we mainly focus on the structural determination of two well-known silk fibroin proteins that are from the domesticated silkworm, bombyx mori, and the wild silkworm, samia cynthia ricini, respectively. the structures of b. mori silk fibroin before and after spinning were determined by usi ...200615132647
complete sequence of the 10.3 kb silkworm attacus ricini rdna repeat, determination of the transcriptional initiation site and functional analysis of the intergenic spacer.a complete sequence of the 10.3 kb silkworm rdna repeat in attacus ricini (also called as samia cynthia ricini) was first determined here, and sequences coding for 18s, 5.8s and 28s were also mapped to rdna unit. the precise transcription initiation site was determined by primer extension experiment. intergenic spacer (igs) in the length of 2670 bp in which transcription of 45s rrna precursor starts was found to contain three distinct at-rich (a + t > 75%) regions. the at-richest region (from -3 ...200312825350
purification and properties of two blue biliproteins from the larval hemolymph and integument of rhodinia fugax (lepidoptera: saturniidae).blue biliproteins (bps) are found in the hemolymph and integument of the fifth instar larvae of the saturniid silkworm, rhodinia fugax. an efficient method of isolating bps from the hemolymph, epidermis and cuticle using hydrophobic interaction chromatography and ion-exchange chromatography was devised. the bps from the hemolymph, epidermis and cuticle have molecular weights of approximately 24,000, 48,000 and 23,000 da by gel-filtration, respectively. using matrix-assisted laser desorption ioni ...19989887515
structure determination of a peptide model of the repeated helical domain in samia cynthia ricini silk fibroin before spinning by a combination of advanced solid-state nmr methods.fibrous proteins unlike globular proteins, contain repetitive amino acid sequences, giving rise to very regular secondary protein structures. silk fibroin from a wild silkworm, samia cynthia ricini, consists of about 100 repeats of alternating polyalanine (poly-ala) regions of 12-13 residues in length and gly-rich regions. in this paper, the precise structure of the model peptide, ggagggyggdgg(a)(12)ggagdgygag, which is a typical repeated sequence of the silk fibroin, was determined using a comb ...200312797796
tightly winding structure of sequential model peptide for repeated helical region in samia cynthia ricini silk fibroin studied with solid-state nmr.there are many kinds of silks from silkworms and spiders with different structures and properties, and thus, silks are suitable to study the structure-property relationship of fibrous proteins. silk fibroin from a wild silkworm, samia cynthia ricini, mainly consists of the repeated similar sequences by about 100 times where there are alternative appearances of the polyalanine (ala)(12-13) region and the gly-rich region. in this paper, a sequential model peptide, ggagggyggdgg(a)(12)ggagdgygag, wh ...200312649423
structural and phylogenetic analysis of tras, telomeric repeat-specific non-ltr retrotransposon families in lepidopteran insects.tras1 is a non-ltr retrotransposon inserted specifically into the telomeric repeat (ttagg)(n) in the silkworm, bombyx mori. to characterize the evolutionary origin of tras-like elements, we identified seven tras families (tras3, tras4, tras5, tras6, trasy, trasz, and trasw) from b. mori and four elements from two lepidoptera, dictyoploca japonica (trasdj) and samia cynthia ricini (trassc3, trassc4, and trassc9). more than 2,000 copies of various bombyx tras elements accumulated within (ttagg)(n) ...200111319268
solid-state nmr determination of the secondary structure of samia cynthia ricini silk.silks are fibrous proteins that form heterogeneous, semi-crystalline solids. silk proteins have a variety of physical properties reflecting their range of functions. spider dragline silk, for example, has high tensile strength and elasticity, whereas other silks are better suited to making housing, egg sacs or the capture spiral of spiders' webs. the differing physical properties arise from variation in the protein's primary and secondary structure, and their packing in the solid phase. the high ...200010890452
prothoracicotropic activity of sbrps, the insulin-like peptides of the saturniid silkworm samia cynthia ricini.synthesis and secretion of the insect molting hormone ecdysteroid in the prothoracic glands (pgs) are stimulated by the prothoracicotropic hormone (ptth) secreted by the brain. bombyxins, insulin-like peptides of the silkworm bombyx mori, show prothoracicotropic activity when administered to the saturniid silkworm samia cynthia ricini, but they are inactive to b. mori itself. recently, the genes for the bombyxin homologs of s. cynthia ricini (referred to as samia bombyxin-related peptides, sbrps ...199910600544
structural analysis of silk with 13c nmr chemical shift contour plots.the polymorphic structures of silk fibroins in the solid state were examined on the basis of a quantitative relationship between the 13c chemical shift and local structure in proteins. to determine this relationship, 13c chemical shift contour plots for c alpha and c beta carbons of ala and ser residues, and the c alpha chemical shift plot for gly residues were prepared using atomic co-ordinates from the protein data bank and 13c nmr chemical shift data in aqueous solution reported for 40 protei ...201310342761
Displaying items 1 - 81 of 81