The Fat Body Transcriptomes of the Yellow Fever Mosquito Aedes aegypti, Pre- and Post- Blood Meal

The Molecular Biology Program, New Mexico State University, Las Cruces, New Mexico, United States of America.
PLoS ONE (Impact Factor: 3.23). 07/2011; 6(7):e22573. DOI: 10.1371/journal.pone.0022573
Source: PubMed


The fat body is the main organ of intermediary metabolism in insects and the principal source of hemolymph proteins. As part of our ongoing efforts to understand mosquito fat body physiology and to identify novel targets for insect control, we have conducted a transcriptome analysis of the fat body of Aedes aegypti before and in response to blood feeding.
We created two fat body non-normalized EST libraries, one from mosquito fat bodies non-blood fed (NBF) and another from mosquitoes 24 hrs post-blood meal (PBM). 454 pyrosequencing of the non-normalized libraries resulted in 204,578 useable reads from the NBF sample and 323,474 useable reads from the PBM sample. Alignment of reads to the existing reference Ae. aegypti transcript libraries for analysis of differential expression between NBF and PBM samples revealed 116,912 and 115,051 matches, respectively. De novo assembly of the reads from the NBF sample resulted in 15,456 contigs, and assembly of the reads from the PBM sample resulted in 15,010 contigs. Collectively, 123 novel transcripts were identified within these contigs. Prominently expressed transcripts in the NBF fat body library were represented by transcripts encoding ribosomal proteins. Thirty-five point four percent of all reads in the PBM library were represented by transcripts that encode yolk proteins. The most highly expressed were transcripts encoding members of the cathepsin b, vitellogenin, vitellogenic carboxypeptidase, and vitelline membrane protein families.
The two fat body transcriptomes were considerably different from each other in terms of transcript expression in terms of abundances of transcripts and genes expressed. They reflect the physiological shift of the pre-feeding fat body from a resting state to vitellogenic gene expression after feeding.

Download full-text


Available from: Peter Houde
  • Source
    • "The most significant advantage of NGS over traditional Sanger-sequencing is its massively parallel sequencing ability with significant low cost for DNA sequencing [10]–[12]. The 454 pyrosequencing is very suitable for a non-model species, enabling high efficient de novo sequencing, assembly and annotation of expressed genes [13], [14], thus has been widely applied in a broad range of arthropod species including Cimex lectularius [15], [16], Anopheles funestus [17], Aedes aegypti [18], Dermacentor variabilis [19], Musca domestica [20], Sarcophaga crassipalpis [21], Cochliomyia hominivorax [22], Anastrepha suspensa [23], Nilaparvata lugens [24],Manduca sexta [25], Lutzomyia intermedia [26], Amblyomma maculatum [27], Corethrella appendiculata [28] and Rhodnius prolixus [29]. For the German cockroach, Illumina sequencing was used to identify microRNAs from the ovaries and whole body of 6th instar nymphs [30]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background The German cockroach, Blattella germanica, is an important insect pest that transmits various pathogens mechanically and causes severe allergic diseases. This insect has long served as a model system for studies of insect biology, physiology and ecology. However, the lack of genome or transcriptome information heavily hinder our further understanding about the German cockroach in every aspect at a molecular level and on a genome-wide scale. To explore the transcriptome and identify unique sequences of interest, we subjected the B. germanica transcriptome to massively parallel pyrosequencing and generated the first reference transcriptome for B. germanica. Methodology/Principal Findings A total of 1,365,609 raw reads with an average length of 529 bp were generated via pyrosequencing the mixed cDNA library from different life stages of German cockroach including maturing oothecae, nymphs, adult females and males. The raw reads were de novo assembled to 48,800 contigs and 3,961 singletons with high-quality unique sequences. These sequences were annotated and classified functionally in terms of BLAST, GO and KEGG, and the genes putatively coding detoxification enzyme systems, insecticide targets, key components in systematic RNA interference, immunity and chemoreception pathways were identified. A total of 3,601 SSRs (Simple Sequence Repeats) loci were also predicted. Conclusions/Significance The whole transcriptome pyrosequencing data from this study provides a usable genetic resource for future identification of potential functional genes involved in various biological processes.
    Full-text · Article · Sep 2014 · PLoS ONE
  • Source
    • "After the removal of low-quality reads, the Trinity de novo assembler ( [48, 49] assembled processed reads with an identity value of 95% and a coverage length of 100 bp [48, 49]. First, the overlap information in the short reads was used to construct high-coverage contigs, and then the short reads were assembled into contigs. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Magnolia sprengeri Pamp is one of the most highly valuable medicinal and ornamental plants of the Magnolia Family. The natural color of M. sprengeri is variable. The complete genome sequence of M. sprengeri is not available; therefore we sequenced the transcriptome of white and red petals of M. sprengeri using Illumina technology. We focused on the identity of structural and regulatory genes encoding the enzymes involved in the determination of flower color. Results We sequenced and annotated a reference transcriptome for M. sprengeri, and aimed to capture the transcriptional determinanats of flower color. We sequenced a normalized cDNA library of white and red petals using Illumina technology. The resulting reads were assembled into 77,048 unique sequences, of which 28,243 could be annotated by Gene Ontology (GO) analysis, while 48,805 transcripts lacked GO annotation. The main enzymes involved in the flavonoid biosynthesis, such as phenylalanine ammonia-Lyase, cinnamat-4-Hydroxylase, dihydroflavonol-4-reductase, flavanone 3-hydroxylase, flavonoid-3′-hydroxylase, flavonol synthase, chalcone synthase and anthocyanidin synthase, were identified in the transcriptome. A total of 270 transcription factors were sorted into three families, including MYB, bHLH and WD40 types. Among these transcription factors, eight showed 4-fold or greater changes in transcript abundance in red petals compared with white petals. High-performance liquid chromatography analysis of anthocyanin compositions showed that the main anthocyanin in the petals of M. sprengeri is cyanidin-3-O-glucoside chloride and its content in red petals was 26-fold higher than that in white petals. Conclusion This study presents the first next-generation sequencing effort and transcriptome analysis of a non-model plant from the Family Magnoliaceae. Genes encoding key enzymes were identified and the metabolic pathways involved in biosynthesis and catabolism of M. sprengeri flavonoids were reconstructed. Identification of these genes and pathways adds to the current knowledge of the molecular biology and biochemistry of their production in plant. Such insights into the mechanisms supporting metabolic processes could be used to genetically to enhance flower color among members of the Magnoliaceae. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-706) contains supplementary material, which is available to authorized users.
    Full-text · Article · Aug 2014 · BMC Genomics
  • Source
    • "In mosquitoes, fat body and salivary glands play important roles in several immune pathways and in antimicrobial peptide production controlling infection by pathogens including virus. It has been demonstrated that a change in gene expression related to fat body and salivary gland function affects vectorial capacity [29, 30]. In the illumina data, a number of transcripts related to salivary proteins were also differentially expressed. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Understanding mechanisms that contribute to viral dissemination in mosquito vectors will contribute to our ability to interfere with the transmission of viral pathogens that impact public health. The expression of genes in two Culex pipiens quinquefasciatus populations from Florida with known differences in vector competence to West Nile virus (WNV) were compared using high throughput sequencing. Results A total of 15,176 transcripts were combined for comparison of expression differences between the two populations and 118 transcripts were differentially expressed (p < 0.05). The fold change in expression of the differentially expressed genes ranged from -7.5 – 6.13. The more competent population for WNV (Gainesville) over expressed 77 genes and down regulated 44 genes, compared with the less competent population for WNV (Vero Beach). Also, splicing analysis identified 3 transcripts with significantly different splice forms between the two populations. The functional analysis showed that the largest proportion of transcripts was included in the catalytic activity and transporter activity groups except for those in the unknown group. Interestingly, the up- regulated gene set contained most of the catalytic activity function and the down- regulated gene set had a notable proportion of transcripts with transporter activity function. Immune response category was shown in only the down regulated gene set, although those represent a relatively small portion of the function. Several different vitellogenin genes were expressed differentially. Based on the RNAseq data analysis, ovary development was compared across the populations and following WNV infection. There were significant differences among the compared groups. Conclusions This study suggests that ovary development is correlated to vector competence in two Culex populations in Florida. Both populations control energy allocations to reproduction as a response to WNV. This result provides novel insight into the defense mechanism used by Culex spp. mosquitoes against WNV.
    Full-text · Article · Jun 2014 · BMC Genomics
Show more