Transcription Profiling Associated With Life Cycle of Anopheles gambiae

Abstract

Complex biological events occur during the developmental process of the mosquito Anopheles gambiae (Giles). Using cDNA expression microarrays, the expression patterns of 13,440 clones representing 8,664 unique transcripts were revealed from six different developmental stages: early larvae (late third instar/early fourth instar), late larvae (late fourth instar), early pupae (< 30 min after pupation), late pupae (after tanning), and adult female and male mosquitoes (24 h postemergence). After microarray analysis, 560 unique transcripts were identified to show at least a fourfold up- or down-regulation in at least one developmental stage. Based on the expression patterns, these gene products were clustered into 13 groups. In total, eight genes were analyzed by quantitative real-time polymerase chain reaction to validate microarray results. Among 560 unique transcripts, 446 contigs were assigned to respective genes from the An. gambiae genome. The expression patterns and annotations of the genes in the 13 groups are discussed in the context of development including metabolism, transport, protein synthesis and degradation, cellular processes, cellular communication, intra- or extra-cellular architecture maintenance, response to stress or immune-related defense, and spermatogenesis.

Stage-specific transcription during development of Aedes aegypti

“…This is also reflected from gene expression patterns by comparing our A. aegypti microarray data with previously reported microarray data for A. gambiae [22]. Although, Harker et al [23] recently reported gene (n = 8,664) expression profiles of A. gambiae developmental stages, we chose to make comparisons with Koutsos et al [22] data as this represented results for the complete annotated gene set. Three specific developmental stages were comparable to both data sets: 1) larval stage (Lb-Le stage of A. gambiae vs. EL-LL stage of A. aegypti ), 2) late larval – early pupal stage (Le-P stage of A. gambiae vs. LL-EP stage of A. aegypti ) and 3) adult stage (M-F of A. gambiae vs. AM-AF stage of A. aegypti ).…”

“…In the malaria vector mosquito Anopheles gambiae , microarray studies have been performed to study life cycle developmental transcriptome [22,23]. These independent studies identified a total of 1,571 [22] and 560 [23] A. gambiae transcripts, respectively, that showed differential regulation specific to development. Comparative global expression analyses with Drosophila melanogaster revealed a strong positive correlation of development-related expression between orthologous genes [22].…”

RNAi Trigger Delivery into <em>Anopheles gambiae</em> Pupae

“…A recent microarray analysis by Harker et al (2012) identified 560 An. gambiae transcripts that were up-regulated or down-regulated by at least 4-fold during distinct developmental stages, ranging from the embryo to adult.…”

“…gambiae transcripts that were up-regulated or down-regulated by at least 4-fold during distinct developmental stages, ranging from the embryo to adult. Of the 560 transcripts identified, a set of 309 was up-regulated during pupal development 27 . These findings suggest that there are many requirements for differential gene expression throughout mosquito development, including those that occur during the pupal stage, an interval during which the organism undergoes metamorphosis.…”

“…In many insect species, including An. gambiae, genes involved in processes such as development (i.e., pupal cuticular and chitin-binding proteins) [27][28][29][30][31] and immune response (i.e., Toll receptor-like proteins) 27,[32][33][34] are highly expressed during the pupal stage. Once a fully formed adult has emerged, there is continued gene expression in response to environmental and physiological changes , as well as other key genes (i.e., sperm specific protein and cytochrome P450 metabolism enzymes) 27,36 .…”