摘要:

AbstractThe complete sequence of a cDNA clone, isolated from epidermal mRNA ofTenebrio molitorusing a monoclonal antibody raised against an adult‐specific cuticular antigen only present in the hard cuticle, was obtained after primer extension at the 5′ end. From this cDNA sequence, the deduced protein encompasses 199 amino acids (including a signal peptide) with a total molecular weight of 20.7 kDa. The protein exhibits a bipartite structure: glycine‐rich region located in its NH2‐terminal part and a carboxy‐terminal domain sharing homologies with other cuticular proteins of Orthoptera, Diptera and Lepidoptera.In‐situhybridization analysis shows that the corresponding mRNA is present only in epidermal cells secreting the adult fibrous cuticle destined to become heavily sclerotized. In supernumerary pupae obtained after the application of the juvenile hormone analogue (JHA) to newly ecdysed pupae, the mRNA was undetectable, indicating that JHA can prevent the switch to the adult programme. However, in pupal‐adult intermediates, obtained when JHA is applied later, the mRN

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00105.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractTo understand the molecular mechanisms of the larval‐specific transcription ofBombyx morilarval serum protein (BmLSP), we isolated a clone of the BmLSP gene from a genomic library and sequenced a 3.5‐kb fragment. An intron was found in the 5′ noncoding region of the BmLSP gene. A putative transcription start point was determined by primer extension analysis. Genomic Southern hybridization showed that there is one copy of the BmLSP gene in a haploid genome. A database search revealed that the BmLSP gene has presumptive repetitive sequences found in otherB. morigenes, the sequence homologous to ecdysone‐responsive elements and a heptamer sequence found in storage protei

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00106.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe gene encodingAedes albopictusribosomal protein L8 was isolated using a cDNA probe. Based on the deduced amino acid sequence, rpL8 has a mass of 28,605 Da, a pl of 11.97, and contains 9.6% Arg and 11.9% Lys. The rpL8 gene spans 1229 nucleotides, and contains three exons measuring 73, 150, and 648 nucleotides. The first intron is 293 nucleotides long and interrupts an 85‐nucleotide untranslated leader sequence. The AUG codon is located 12 nucleotides downstream of the 5′‐end of the second exon. Separating the second and third exons is a 65‐nucleotide intron. The major transcription initiation site, identified by primer extension and polymerase stop reactions, mapped 378 nucleotides upstream from the AUG start codon; minor initiation sites were also detected. The DNA sequence upstream of the rpL8 gene was T‐rich, but conventional TATA and CAAT boxes were absent. This is the first molecular analysis of a mosquito ribosomal pro

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00107.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractExpression of heat shock proteins (hsp) in the BRL‐AG‐3C cell line from the cotton boll weevil was examined. It was determined that the maximal expression of endogenous hsp occurred at 41°C. Various transfection methods were then compared using this cell line in conjunction with a transiently expressed bacterial gene marker (chloramphenicol acetyltransferase) which was under the control of theDrosophilahsp 70 gene promoter. The cationic lipid preparation Lipofectin was found to be very efficient at transfecting the boll weevil cells. Polylysine and 20‐hydroxyecdysone‐conjugated polylysine were moderately effective, whereas polybrene and electroporation, under the conditions reported herein, were ineffective at transfecting this c

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00108.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractDNA fingerprints (DNAfp) were obtained for three widely separated samples of bee related toLasioglossum marginatumusing the M13 sequence as a probe. Bee samples were obtained from France (three localities separated by at most 20 km), Greece and India. All European populations exhibited almost identical profiles with similarity indices (S) of over 98% within a French sample, 94% among Greek bees and 90% between Greek and French bees. The DNAfp profiles of Indian bees showed more polymorphism (intrapopulationS= 77%) and were quite dissimilar to the European samples (S= 55% and 56% to French and Greek samples, respectively). The similarity between populations separated by over 2000 km is higher than among unrelated individuals within a population in two other bee species and the tsetse fly. Data from allozyme electrophoresis shows parallel variation to that obtained with DNAfp and the genetic differences between Indian and European samples are strikingly large (Indian and European populations shared no alleles at 14 out of 47 loci surveyed) such that no more than one species must be involved. Nonetheless, the samples are indistinguishable morphologically. We argue that chronically low effective population size in these species results in low levels of genetic variability and that this, combined with a genetic bottleneck during the speciation event and colonization of Europe, may have resulted in both the extremely low levels of DNAfp variation in European bees and the large number of fixed allelic differences between European and Indian samples. We conclude that DNAfp may be particularly useful as a tool to study population level phenomena in organisms with only moderate levels of DNAfp variability and that the Hymenoptera may be particularly appropriate model systems for such research.

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00109.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractUsing a gel mobility shift assay, protein factors have been identified that may participate in the transcriptional regulation of the juvenile hormone (JH) induced vitellogenin A (VgA) gene of the migratory locust. Two DNA‐binding proteins were found that were modulated in correlation withVgAgene activity during normal reproductive cycles and experimental stimulation by an active JH analogue (pyriproxyfen). One of these, JH factor (JHF), may be a regulator ofVgAand perhaps other JH‐responsive genes. The second, mobile factor (MF), appears to have a more general role in cellular responses to external stimuli such as JH and wounding. JHF and MF may represent factors that act together with the JH receptor to regulateVgAgene transcript

ISSN:0962-1075    

DOI:10.1111/j.1365-2583.1993.tb00110.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY