A Microarray-based Analysis of Transcriptional Compartmentalization in the Alimentary Canal of Anopheles gambiae

Although the basic anatomical sub-divisions of the larval mosquito gut were established several decades ago, information regarding their exact physiological roles is rather scarce. Several studies have reported differences between larval gut compartments in various morphological and physiological aspects. Unfortunately, the fragmentary and incomplete nature of this information makes it hard to establish clear links to the specific and/or unique physiological roles of each gut region. In this study, we attempted to identify transcripts significantly enriched in each gut section of the 4th instar Anopheles gambiae larva. We took advantage of a commercially-available microarray platform containing ~14,000 different An. gambiae transcripts (Affymetrix GeneChip® Plasmodium/Anopheles array, Affymetrix Inc., Santa Clara, CA). Based on the information obtained, we discuss the putative physiological roles of each major compartment of the larval gut, and identify potential new targets for larval control strategies. Keywords: tissue comparison We attempted to identify transcripts significantly enriched in each gut section of the 4th instar Anopheles gambiae larva. Signal intensities of transcripts from each gut section were compared to those of a matching group of whole 4th instar larvae using t-tests. Transcripts showing an intensity value two-fold or higher (p < 0.05) in each gut section as compared to whole larvae were considered to be significantly enriched.