bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for two juvenile hormone esterase‐related genes in the Colorado potato beetle
Authors: Vermunt A. M. W. , Koopmanschap A. B. , Vlak J. M. , de Kort C. A. D. 
Published: March 2003

AbstractJuvenile hormone esterase (JHE) activity in the haemolymph of the Colorado potato beetle is necessary to initiate pupation in larvae as well as diapause in adults. The enzyme appears in the haemolymph as a dimer consisting of two 57 kDa subunits. The sequence of an encoding cDNA, JHE.A, is distinct from lepidopteran JHEs. In this study, RT‐PCR using primers designed on the basis of the 5′‐ and 3′‐ends of the coding region revealed the existence of a related gene, JHE.B. The presence of two JHE‐related genes was also shown by PCR amplification on genomic DNA from different individual beetles followed by restriction enzyme analysis. Both forms, probably paralogues, were transcribed since they could be amplified on messenger RNA from fat bodies. The size of the PCR products generated with mRNA and genomic DNA were both 1.6 kb, suggesting the absence of introns in the genomic JHE coding sequence. The sequence of a genomic clone, which encoded JHE.B, was 77% identical and 82% similar in amino acids compared to JHE.A. No introns were found in the coding sequence of these coleopteran JHE‐related genes, in contrast to lepidopteran JHE genes. Southern blot analysis of digested genomic DNA confirmed the presence of two JHE‐related genes.
Tissue tropism, transmission and expression of foreign genes in vivo in midgut symbionts of tsetse flies
Authors: Cheng Q. , Aksoy S. 
Published: March 2003

AbstractTsetse flies (Diptera: Glossinidae) harbour three different symbiotic organisms in addition to the pathogenic African trypanosomes they transmit. The two gut‐associated symbionts (primary, P; secondary, S) are enteric and are nutritionally required, whereas the third microorganism Wolbachia (family Rickettsiaceae) affects the reproductive biology of the insects it infects. The bacteriome‐associated P‐symbiont (Wigglesworthia glossinidia) displays a concordant phylogeny with its host tsetse species, whereas midgut S‐symbionts characterized from distant tsetse have identical 16S rDNA sequences and therefore may either represent recent independent acquisitions or horizontal transfer between species. The S‐symbionts have been cultured in vitro and a genetic transformation system has been developed. Here we report on their density and tissue tropism in different species (G. m. morsitans, G. p. palpalis, G. austeni and G. brevipalpis) and on their maternal route of transmission to tsetse progeny. Using a bacterium‐specific PCR‐assay, the S‐symbionts were found primarily in the midgut, haemolymph, milk gland and in G. palpalis also in salivary glands of teneral flies. In older flies these infections were found to spread to other tissues including muscle, testes and fat body. The S‐symbionts were transformed to express the marker gene product, Green Fluorescent Protein (GFP) in vitro. When the recombinant symbionts were introduced into the haemoceal of fertile female flies via intrathoracic microinjection, they were detected in the intrauterine progeny, indicating that haemolymph may provide a possible route for their transmission. The implications of these results for symbiont‐host interactions and for transgenic strategies in tsetse are discussed.
Characterization of a carboxypeptidase A gene from the mosquito, Aedes aegypti
Authors: Edwards M. J. , Moskalyk L. A. , Donelly‐Doman M. , Vlaskova M. , Noriega F. G. , Walker V. K. , Jacobs‐Lorena M. 
Published: March 2003

AbstractA gut‐specific carboxypeptidase A gene (AeCPA) from the mosquito, Aedes aegypti, was cloned and characterized. The gene has an open reading frame that predicts a protein of 427 amino acids, 61% of which are identical to an Anopheles gambiae carboxypeptidase A sequence. AeCPA messenger RNA (mRNA) was not detected during larval and pupal development. In situ hybridization experiments indicated that AeCPA mRNA is expressed by posterior midgut epithelial cells. In sharp contrast to An. gambiae carboxypeptidase A gene expression, AeCPA mRNA accumulates to high levels only late (≈ 16–24 h) after ingestion of a blood meal. The temporal profile of AeCPA gene induction is similar to that of Ae. aegypti late trypsin, suggesting the existence of common regulatory elements.
Expression patterns of the larval and adult hexamerin genes of Musca domestica
Authors: Capurro M. de L. , Moreira‐Ferro C. K. , Marinotti O. , James A. A. , De Bianchi A. G. 
Published: March 2003

AbstractHexamerins are proteins found in high abundance in the haemolymph of larval and adult insects. The expression patterns of the genes encoding the house fly, Musca domestica, hexamerins were determined by Northern analyses using cDNAs as probes. A cDNA, A1, hybridized to a fat body‐specific messenger RNA (mRNA) which is detectable in larvae until pupation. Antibodies raised to the larval‐specific hexamerin, Hex‐L, bind recombinant protein encoded by a 5′ rapid amplification of cDNA ends (
race) product of A1, A2, indicating that the A cDNAs likely represent the genes encoding Hex‐L. The F1, F2 and F3 cDNAs, corresponding to genes encoding an adult, female‐enriched hexamerin, Hex‐F, hybridized with an mRNA isolated from protein‐fed females which has a temporal expression profile similar to that observed for the accumulation of Hex‐F. Furthermore, expression of the mRNAs hybridizing to the F cDNAs is correlated with the abundance of Hex‐F protein during the gonotrophic cycles. The mRNA transcription profiles indicate that the Hex‐L and Hex‐F genes are regulated in a sex‐, tissue‐ and developmental phase‐dependent manner. This stage‐specific expression of hexamerins contrasts with the expression patterns of hexamerins seen in other insects. The conceptual translation products of larval hexamerin cDNAs showed identity with larval serum protein 1 (LSP1)‐type hexamerins while the deduced products of the female hexamerin cDNAs showed the highest identity with LSP2‐type hexamerins. Genomic analyses showed that the larval hexamerin and female hexamerin genes from M. domestica belong to two distinct multigenic families.
Ribosomal DNA internal transcribed spacer (ITS2) sequences differentiate Anopheles funestus and An. rivulorum, and uncover a cryptic taxon
Authors: Hackett B. J. , Gimnig J. , Guelbeogo W. , Costantini C. , Koekemoer L. L. , Coetzee M. , Collins F. H. , Besansky N. J. 
Published: March 2003

AbstractDifferentiation among the closely related Afrotropical species comprising the Funestus Group is difficult by traditional taxonomic measures. Anopheles rivulorum is the second most abundant and widespread species in the Funestus Group, and is occasionally collected indoors along with the dominant member and major malaria vector, An. funestus. The prospect of misidentification of An. rivulorum as An. funestus prompted the development of a rapid, polymerase chain reaction (PCR)‐based method for identifying these two species. The ribosomal internal transcribed spacer 2 (ITS2) was amplified from thirty‐five specimens of An. rivulorum collected from the extremes of its range: Eastern Africa (Kenya), Southern Africa (South Africa) and Western Africa (Burkina Faso). The ITS2 region of An. rivulorum (≈ 380 bp) is sufficiently different in size from the ITS2 of An. funestus (≈ 700 bp) that these species can be distinguished by agarose gel electrophoresis of PCR products without further manipulation. Comparison of the An. rivulorum and An. funestus ITS2 nucleotide sequences revealed such extensive divergence that meaningful alignment was impossible, except for a 25 bp island near the 5′ end. Intraspecific sequence comparisons revealed no variation among An. rivulorum individuals collected from the same country. However, sequence divergence was 2% between specimens from South Africa and Kenya, and nearly tenfold higher (≈ 19%) between specimens from Burkina Faso and either South Africa or Kenya, an unprecedented level of intraspecific ITS2 divergence in Anopheles. Taken together, these data suggest that the Burkina Faso sample is not An. rivulorum, but rather a cryptic taxon within the Funestus Group.
Microsatellite DNA markers reveal genetic differentiation among populations of Glossina palpalis gambiensis collected in the agro‐pastoral zone of Sideradougou, Burkina Faso
Authors: Solano P. , De La Rocque S. , De Meeus T. , Cuny G. , Duvallet G. , Cuisance D. 
Published: March 2003

AbstractIntraspecific genetic variability of Glossina palpalis gambiensis in the area of Sideradougou, Burkina Faso, was studied using polymorphic microsatellite DNA markers. This genetic study was combined with other epidemiological information on the same tsetse: bloodmeal identification, dissection of tsetse and molecular characterization of the trypanosomes detected. There was significant genetic differentiation among flies caught only a few kilometers apart, within the same riverine habitat. These distinct subpopulations were also differentially infected by trypanosomes. In part of the study area, a Factorial Correspondence Analysis undertaken on the genotypes allowed us to detect a Wahlund effect, suggesting the presence of tsetse originating from different source populations coming from two distinct drainage systems. The apparent structuring of populations of G. palpalis gambiensis is discussed relative to appropriate strategies to control African Trypanosomosis.
The piggyBac transposon mediates germ‐line transformation in the Oriental fruit fly and closely related elements exist in its genome
Authors: Handler A. M. , McCombs S. D. 
Published: March 2003

AbstractGerm‐line transformation of a white eye strain of the Oriental fruit fly, Bactrocera dorsalis, was achieved with the piggyBac vector, derived from a transposon originally isolated from the cabbage looper moth, Trichoplusia ni. The vector was marked with the medfly white+ gene cDNA, and three transgenic lines were identified at a frequency of approximately 2% per fertile G0. Vector integrations were verified by Southern DNA hybridization, which also revealed the presence of endogenous genomic elements closely related to piggyBac. Approximately 10–20 elements per genome were evident in several B. dorsalis strains, and sequence analysis of 1.5 kb gene amplification products from two wild strains and the white eye host strain indicated 95% nucleotide and 92% amino acid sequence identity among resident elements and the T. ni element. PiggyBac was not evident by hybridization in other tephritid species, or insects previously transformed with the transposon. This is the first discovery of piggyBac beyond T. ni, and its existence in a distantly related species has important implications for the practical use of the vector and insects transformed with it.
Wolbachiainfections in native and introduced populations of fire ants (Solenopsisspp.)
Authors: Shoemaker D. DeWayne , Ross Kenneth G. , Keller L. , Vargo E. L. , Werren John H. 
Published: March 2003

AbstractWolbachiaare cytoplasmically inherited bacteria that induce a variety of effects with fitness consequences on host arthropods, including cytoplasmic incompatibility, parthenogenesis, male‐killing and feminization. We report here the presence ofWolbachiain native South American populations of the fire antSolenopsisinvicta, but the apparent absence of the bacteria in introduced populations of this pest species in the USA. TheWolbachiastrains in nativeS. invictaare of two divergent types (A and B), and the frequency of infection varies dramatically between geographical regions and social forms of this host. Survey data reveal thatWolbachiaalso are found in other native fire ant species within theSolenopsis saevissimaspecies complex from South America, includingS. richteri. This latter species also has been introduced in the USA, where it lacksWolbachia. Sequence data reveal complete phylogenetic concordance between mtDNA haplotype inS.invictaandWolbachiainfection type (A or B). In addition, the mtDNA and associated group AWolbachiastrain inS.invictaare more closely related to the mtDNA andWolbachiastrain found inS. richterithan they are to the mtDNA and associated group BWolbachiainS. invicta. These data are consistent with historical introgression ofS. richtericytoplasmic elements intoS.invictapopulations, resulting in enhanced infection and mtDNA polymorphisms inS. invicta.Wolbachiamay have significant fitness effects on these hosts (either directly or by cytoplasmic incompatibility) and therefore these microbes potentially could be used in biological control programmes to suppress introduced fire ant populations.
Molecular cloning of two prophenoloxidase genes from the mosquito Aedes aegypti
Authors: Taft A. S. , Chen C. C. , Li J. , Christensen B. M. 
Published: March 2003

AbstractThe biosynthesis of melanotic materials is an important process in the life of a mosquito. Melanin production is critical for many diverse processes such as egg chorion tanning, cuticular sclerotization, and melanotic encapsulation of metazoan parasites. Prophenoloxidase plays a critical role in this biochemical cascade. Two cDNAs, one full length and one partial clone, and two genomic clones encoding prophenoloxidase (pro‐PO) were isolated from the yellow fever mosquito, Aedes aegypti. The full‐length cDNA, pAaProPO1, is 2286 bp long with a 2055 bp open reading frame encoding a 685 amino acid protein that shares 89% identity with Armigeres subalbatus pro‐PO. It contains two putative copper binding domains (amino acids 197–243 and 346–423) that are homologous to other insect pro‐POs. AaProPO1 messenger RNA (mRNA) was detected by reverse transcription polymerase chain reaction (RT‐PCR) only from third‐stage larvae and not in adult mosquitoes after blood feeding, during the melanotic encapsulation of Dirofilaria immitis microfilariae or following exposure to bacteria. A 750 bp fragment of the second cDNA (pAaProPO2) was cloned using RT‐PCR from mRNA obtained from 14‐day postovipostional eggs. AaProPO2 mRNA was not found in any other life stages, and may be in low abundance or transiently expressed. AaProPO2 and AaProPO1 each contain three introns that are 60, 68 and 58 bp and 61, 69 and 59 bp long, respectively, and the intron sequences of these two genes are not similar.
Hermes‐mediated germ‐line transformation of the Mediterranean fruit fly Ceratitis capitata
Authors: Michel K. , Stamenova A. , Pinkerton A. C. , Franz G. , Robinson A. S. , Gariou‐Papalexiou A. , Zacharopoulou A. , O'Brochta D. A. , Atkinson P. W. 
Published: March 2003

AbstractWe report the use of the Hermes transposable element for germ‐line transformation of the Mediterranean fruit fly, Ceratitis capitata. Hermes was able to genetically transform this insect at an estimated frequency between 0.6 and 1.1%, which is comparable to the transformation frequencies obtained for this species when using other transposable elements. Hermes integrates into the medfly genome by a cut‐and‐paste mechanism and the sequences integrated into the genome are delimited by the terminal nucleotides of the Hermes inverted terminal repeats. Integration resulted in the generation of 8 bp target site duplications, the sequences of which conformed to the target site duplications generated by hAT element transposition in insects. The Hermes element is one additional genetic tool that can be deployed in manipulating and characterizing the medfly genome.
Expression and immunolocalization of a Boophilus microplus cathepsin L‐like enzyme
Authors: Renard Gaby , Lara Flávio Alves , De Cardoso Felipe Cardoso , Miguens Flávio Costa , Dansa‐Petretski Marílvia , Termignoni Carlos , Masuda Aoi 
Published: March 2003

AbstractEfforts are being undertaken to control tick infestations that cause important economic losses. A cathepsin L‐like endopeptidase of Boophilus microplus was expressed in Escherichia coli; the recombinant enzyme was capable of hydrolysing gelatin, tick vitellin and bovine haemoglobin. In this paper we focus on the expression and local of synthesis of this enzyme in the tick. RT‐PCR experiments showed that this endopeptidase is transcribed in the gut of partially engorged tick females. In immunoblotting, polyclonal antibodies against the recombinant enzyme reacted with proteins of larvae older than 5 days, of fully and partially engorged female gut. In immunolocalization experiments the enzyme was localized in probable secretory cells of the gut. Based on our findings we postulate that BmCL1 may be involved in haemoglobin degradation in the B. microplus gut. This enzyme may be used as target for the control of this parasite.
Linkage analysis of maternal EST cDNA clones covering all twenty‐eight chromosomes in the silkworm, Bombyx mori
Authors: Kadono‐Okuda K. , Kosegawa E. , Mase K. , Hara W. 
Published: March 2003

AbstractA cDNA library of maternal messages was constructed from non‐fertilized Bombyx mori eggs collected just after oviposition without mating. cDNA clones were identified by their nucleotide sequences and evaluated as probes for RFLP linkage analysis. Back crossed F1 segregants – by crossing an F1 female (RF02 × RF50) and a male (RF02) – were used, which takes advantage of the phenomenon that no crossing over occurs in Bombyx females. Fifteen ordered BF1 segregants gave either homozygous (homo) or heterozygous (hetero) RFLP patterns with each cDNA probe. cDNA probes on the same linkage group gave the same homo/hetero order. One hundred and fifty one out of 248 cDNA clones showed polymorphisms between RF02 and RF50, and were therefore suitable as probes for RFLP linkage analysis in the present BF1 cross. They were sorted into twenty‐seven linkage groups and one independent group, by the homo/hetero pattern matrix, covering all twenty‐eight chromosomes in B. mori.
Expression of proteasome subunit isoforms during spermatogenesis in Drosophila melanogaster
Authors: Ma J. , Katz E. , Belote J. M. 
Published: March 2003

AbstractIn this study, we sought to identify and characterize all the proteasome genes of Drosophila melanogaster. Earlier work led to the identification of two genes encoding α4‐type 20S proteasome subunit isoforms that are expressed exclusively in the male germline. Here we extend these results and show that six of the 20S proteasome subunits, and four of the 19S regulatory cap subunits, have gene duplications encoding male‐specific isoforms. More detailed analyses of two of these male‐specific subunits (Prosα3T and Prosα6T), using GFP‐tagged reporter transgenes, revealed that they are predominantly localized to the nucleus at later stages of spermatogenesis and are present there in mature, motile sperm. These results suggest a possible role of a ‘spermatogenesis‐specific’ proteasome in sperm differentiation and/or function.
Cloning and characterization of a 70 kDa heat shock cognate gene (HSC70) from two species of Chironomus
Authors: Karouna‐Renier N. K. , Yang W.‐J. , Rao K. Ranga 
Published: March 2003

AbstractIn the present study we carried out the isolation and characterization of an HSC70 gene from two midges, Chironomus tentans and C. yoshimatsui. The HSC70 cDNAs are approximately 2424 (C. tentans) and 2464 bp (C. yoshimatsui) long, and contain 1950 and 1956 bp open reading frames, respectively. Analysis of genomic DNA revealed the presence of two introns in these genes. The 5′ untranslated regions of the HSC70 genes are adenosine‐rich, a feature found in inducible HSP70 genes. The nucleotide and amino acid sequences exhibit high identity with cytosolic HSC70s from other Dipterans. Northern hybridization indicated that HSC70 is expressed at all developmental stages, from embryo to adult, and Southern hybridization confirmed the presence of multiple HSP70 genes in Chironomus.
Isolation and expression of a sterol carrier protein‐2 gene from the yellow fever mosquito, Aedes aegypti
Authors: Krebs K. C. , Lan Q. 
Published: March 2003

AbstractTrafficking of cholesterol in insects is a very important process due to the fact that insects depend on dietary cholesterol to fulfil their physiological needs. We identified a putative mosquito sterol carrier protein‐2 (SCP‐2) cDNA from fourth instar subtracted cDNA library. The AeSCP‐2 protein has high degree homology in the sterol transfer domain to both rat and human SCP‐2. Transcripts of AeSCP‐2 in fourth instars were detected strongly in the midgut, and weakly in the head and hindgut. In the early pupae, AeSCP‐2 transcription was observed in the thorax, head and body wall of abdomen, but not in the gut.The interaction of mosquito sterol carrier protein‐2 (AeSCP‐2) with cholesterol was examined. The Kd of purified recombinant AeSCP‐2 to cholesterol was 5.6 ± 0.6 × 10−9 m using radiolabelled cholesterol‐binding assay. The results suggest that AeSCP‐2 has high affinity to cholesterol and may function as a carrier protein in mosquitoes.
Characterization of three Toll‐like genes from mosquito Aedes aegypti
Authors: Luna C. , Hoa N. T. , Zhang J. , Kanzok S. M. , Brown S. E. , Imler J.‐L. , Knudson D. L. , Zheng L. 
Published: March 2003

AbstractThree Toll‐related genes (AeToll1A, AeToll1B and AeToll5) were cloned and characterized from the yellow fever vector mosquito, Aedes aegypti. All three genes exhibited high levels of amino acid sequence similarity with Drosophila melanogaster (Dm)Toll1 and DmTehao (Toll5). AeToll1A and AeToll1B are 1124 and 1076 amino acid residues long, respectively. Both contain a carboxyl extension downstream of the Toll/interleukin‐1 receptor (TIR) domain. AeToll5 is 1007 residues long and, like DmTehao, lacks the carboxyl terminal extension. Expression of these three genes was examined throughout development and after immune challenge. Both AeToll1A and AeToll5, like their Drosophila counterparts, activate transcription of drosomycin promoter in both Aedes and Drosophila cell lines. Deletion of the carboxyl extension of AeToll1A did not result in a further elevated level of the antifungal response. The intracellular signalling process appears to be species specific based on two observations. (1) DmToll is completely inactive in an Aedes cell line, suggesting a higher specificity requirement for DmToll in the intracellular signalling process. (2) Only one of three amino acid residues essential for DmToll function is required for AeToll1A function.
Application of 16S rDNA‐DGGE to examine the microbial ecology associated with a social wasp Vespula germanica
Authors: Reeson A. F. , Jankovic T. , Kasper M. L. , Rogers S. , Austin A. D. 
Published: March 2003

AbstractInvertebrates host numerous bacteria, with interactions ranging from pathogenesis to symbiosis. While certain symbiotic relationships have been well studied, little is known about the dynamics of these bacterial communities. Denaturing gradient gel electrophoresis (DGGE) was used to examine the bacterial microflora associated with the eusocial wasp Vespula germanica. DGGE profiles of larval guts revealed a variable microflora, suggesting that V. germanica is not dependent on a particular suite of mutualists. The variation in profiles was not related to season, nest size or macrohabitat. Sequences corresponding to Lactococcus, Lactobacillus, a novel Leuconostoc and two Rickettsiella grylli strains were obtained. DGGE proved to be a useful technique for characterizing the wasp microflora. Given the importance of microbial communities to invertebrates, there is much to be gained from the application of such techniques.