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51.
JOHN STOUT BENJAMIN NAVIA JASON JEFFERY LESLIE SAMUEL LAURA HARTWIG ASHLEY BUTLIN MARY CHUNG JESSICA WILSON ERICA DASHNER GORDON ATKINS 《Physiological Entomology》2010,35(2):99-116
Earlier studies of phonotaxis by female crickets describe this selective behavioural response as being important in the females' choices of conspecific males, leading to reproduction. In the present study, moderate (30+) to very large data sets of phonotactic behaviour by female Acheta domesticus L., Gryllus bimaculatus DeGeer, Gryllus pennsylvanicus Burmeister and Gryllus veletis Alexander demonstrate substantially greater plasticity in the behavioural choices, as made by females of each species, for the syllable periods (SP) of model calling songs (CS) than has been previously described. Phonotactic choices by each species range from the very selective (i.e. responding to only one or two SPs) to very unselective (i.e. responding to all SPs presented). Some females that do not respond to all SPs prefer a range that includes either the longest or shortest SP tested, which fall outside the range of SPs produced by conspecific males. Old female A. domesticus and G. pennsylvanicus are more likely to be unselective for SPs than are young females. Each species includes females that do not respond to a particular SP when responding to CSs with longer and shorter SPs. The results suggest that the plasticity of phonotactic behaviour collectively exhibited by the females of each species does not ensure that choices of a male's CS effectively focus the female's phonotactic responses on CSs that represent the conspecific male. The phonotactic behaviour collectively exhibited by females of each species does not readily fit any of the models for selective processing by central auditory neurones that have been proposed to underlie phonotactic choice. 相似文献
52.
Stored Messenger Ribonucleoprotein Particles in Differentiated Sclerotia of Physarum polycephalum 总被引:1,自引:0,他引:1
DAVID S. ADAMS DANIEL NOONAN WILLIAM R. JEFFERY 《Differentiation; research in biological diversity》1981,20(1-3):177-187
Starvation induces vegetative microplasmodia of Physarum polycephalum to differentiate into translationally-dormant sclerotia. The existence and the biochemical nature of stored mRNA in sclerotia is examined in this report. The sclerotia contain about 50% of the poly(A)-containing RNA [poly(A)+RNA] complement of microplasmodia as determined by [3 H]-poly(U) hybridization. The sclerotial poly(A)+RNA sequences are associated with proteins in a ribonucleoprotein complex [poly(A)+mRNP] which sediments more slowly than the polysomes. Sclerotial poly(A)+RNP sediments more rapidly than poly(A)+RNP derived from the polysomes of microplasmodia despite the occurrence of poly(A)+RNA molecules of a similar size in both particles suggesting the existence of differences in protein composition. Isolation of poly(A)+RNP by oligo (dT)-cellulose chromatography and the analysis of its associated proteins by polyacrylamide gel electrophoresis show that sclerotial poly(A)+RNP contains at least 14 major polypeptides, 11 of which are different in electrophoretic mobility from the polypeptides found in polysomal poly(A)+RNP. Three of the sclerotial poly(A)+RNP polypeptides are associated with the poly(A) sequence (18, 46, and 52 × 103 mol. wt. components), while the remaining eight are presumably bound to non-poly(A) portions of the poly(A)+RNA. Although distinct from polysomal poly(A)+RNP, the sclerotial poly(A)+RNP is similar in sedimentation behavior and protein composition (with two exceptions) to the microplasmodial free cytoplasmic poly(A)+RNP. The results suggest that dormant sclerotia store mRNA sequences in association with a distinct set of proteins and that these proteins are similar to those associated with the free cytoplasmic poly(A)+RNP of vegetative plasmodia. 相似文献
53.
ABSTRACT. The mitochondrion appears to be essential for the growth of asexual, intraerythrocytic stages of Plasmodium falciparum and may thus be a suitable chemotherapeutic target. The in vitro activity of almitrine, a mitochondrial ATP synthetase inhibitor used for the treatment of hypoxemia, was compared with other mitochondrial inhibitors against chloroquine-susceptible and chloroquine-resistant P. falciparum using an isotopic semimicro drug susceptibility assay. The 50% inhibitory concentration (IC50) values of almitrine (range: 2.6–19.8 μM) were within similar range of values of other mitochondrial ATP synthetase inhibitors and doxycycline, a mitochondrial protein synthesis inhibitor. Almitrine was equally active against chloroquine-susceptible and chloroquine-resistant parasites. Drug combination studies showed no interaction between chloroquine and almitrine. Our results suggest that almitrine, a clinically safe drug, may represent a lead compound with a specific target against the mitochondrial ATP synthetase which may be useful for antimalarial chemotherapy. 相似文献
54.
Revisiting Coptotermes (Isoptera: Rhinotermitidae): a global taxonomic road map for species validity and distribution of an economically important subterranean termite genus 下载免费PDF全文
THOMAS CHOUVENC HOU‐FENG LI JAMES AUSTIN CHRISTIAN BORDEREAU THOMAS BOURGUIGNON STEPHEN L. CAMERON ELIANA M. CANCELLO REGINALDO CONSTANTINO ANA MARIA COSTA‐LEONARDO PAUL EGGLETON THEODORE A. EVANS BRIAN FORSCHLER J. KENNETH GRACE CLAUDIA HUSSENEDER JAN KŘEČEK CHOW‐YANG LEE TIMOTHY LEE NATHAN LO MATTHEW MESSENGER AARON MULLINS ALAIN ROBERT YVES ROISIN RUDOLF H. SCHEFFRAHN DAVID SILLAM‐DUSSÈS JAN ŠOBOTNÍK ALLEN SZALANSKI YOKO TAKEMATSU EDWARD L. VARGO AKINORI YAMADA TSUYOSHI YOSHIMURA NAN‐YAO SU 《Systematic Entomology》2016,41(2):299-306
55.
Abstract. 1. The species of Simulium present at twenty-seven stations in the River Frome and some of its tributaries are recorded.
2. In the lower reaches of the river Simulium omatum and Simulium lineatum have basic life histories comprising four generations of larvae annually.
3. At other stations the annual pattern is modified by weed cutting and flow regulations and by position in the river system.
4. In winter generations the larvae and pupae are larger than at other times of the year. A survey of the size of pupae at ten stations in October 1973 indicated that temperature could account for variations in size. 相似文献
2. In the lower reaches of the river Simulium omatum and Simulium lineatum have basic life histories comprising four generations of larvae annually.
3. At other stations the annual pattern is modified by weed cutting and flow regulations and by position in the river system.
4. In winter generations the larvae and pupae are larger than at other times of the year. A survey of the size of pupae at ten stations in October 1973 indicated that temperature could account for variations in size. 相似文献
56.
Genome‐wide survey of Tribolium castaneum microsatellites and description of 509 polymorphic markers
JEFFERY P. DEMUTH DOUGLAS W. DRURY MORGAN L. PETERS J. DAVID VAN DYKEN NICHOLAS K. PRIEST MICHAEL J. WADE 《Molecular ecology resources》2007,7(6):1189-1195
We survey the Tribolium castaneum whole genome sequence for 1–6 bp microsatellite motifs. Of the > 12 000 microsatellites discovered, we screened 981 primer pairs which yielded 509 polymorphic markers. We report polymorphism data for pooled DNA samples from three to 11 geographically widespread T. castaneum populations as well as heterozygosity for a subset of the markers. The composition and chromosomal distribution of microsatellites is briefly discussed in relation to previous studies. 相似文献
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