Differential gene expression in abdomens of the malaria vector mosquito, Anopheles gambiae, after sugar feeding, blood feeding and Plasmodium berghei infection.
BACKGROUND
Large scale sequencing of cDNA libraries can provide profiles of genes expressed in an organism under defined biological and environmental circumstances. We have analyzed sequences of 4541 Expressed Sequence Tags (ESTs) from 3 different cDNA libraries created from abdomens from Plasmodium infection-susceptible adult female Anopheles gambiae. These libraries were made from sugar fed (S), rat blood fed (RB), and P. berghei-infected (IRB) mosquitoes at 30 hours after the blood meal, when most parasites would be transforming ookinetes or very early oocysts.


RESULTS
The S, RB and IRB libraries contained 1727, 1145 and 1669 high quality ESTs, respectively, averaging 455 nucleotides (nt) in length. They assembled into 1975 consensus sequences--567 contigs and 1408 singletons. Functional annotation was performed to annotate probable molecular functions of the gene products and the biological processes in which they function. Genes represented at high frequency in one or more of the libraries were subjected to digital Northern analysis and results on expression of 5 verified by qRT-PCR.


CONCLUSIONS
13% of the 1965 ESTs showing identity to the A. gambiae genome sequence represent novel genes. These, together with untranslated regions (UTR) present on many of the ESTs, will inform further genome annotation. We have identified 23 genes encoding products likely to be involved in regulating the cellular oxidative environment and 25 insect immunity genes. We also identified 25 genes as being up or down regulated following blood feeding and/or feeding with P. berghei infected blood relative to their expression levels in sugar fed females.
Dana
Ali N
AN
Center for Tropical Disease Research and Training, Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA. adana@iupui.edu
Hillenmeyer
Maureen E
ME
Lobo
Neil F
NF
Kern
Marcia K
MK
Romans
Patricia A
PA
Collins
Frank H
FH
D000005:Abdomen; D000818:Animals; D000852:Anopheles / Q000235:genetics* / Q000378:metabolism / Q000469:parasitology; D001769:Blood; D015152:Blotting, Northern; D002241:Carbohydrates / Q000008:administration & dosage; D004435:Eating; D020224:Expressed Sequence Tags; D005260:Female; D005786:Gene Expression Regulation; D015723:Gene Library; D017344:Genes, Insect; D007303:Insect Vectors / Q000235:genetics* / Q000378:metabolism / Q000469:parasitology; D010962:Plasmodium berghei; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017421:Sequence Analysis
D002241:Carbohydrates