Transcription profiling associated with life cycle of Anopheles gambiae.

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.

Anatomical ontologies of mosquitoes and ticks, and their web browsers in VectorBase.

VectorBase, an integrated, relational database that manages genomic and other genetic/biological data pertaining to arthropod vectors of disease, has recently embarked on the construction of ontologies and controlled vocabularies (CVs). It aims, thus, at providing all necessary tools for the complete annotation of vector genomes and, in particular, the annotation of functional genomic data. This task was initiated with the development of anatomical ontologies of mosquitoes and ticks, both of which were made compliant to CARO, the common anatomy reference ontology. The ontologies are complemented by the development of novel web-based browsers that can show figures for anatomical terms, something that is especially helpful for fully illustrating the controlled vocabularies of anatomy.

Genomic resources for invertebrate vectors of human pathogens, and the role of VectorBase.

High-throughput genome sequencing techniques have now reached vector biology with an emphasis on those species that are vectors of human pathogens. The first mosquito to be sequenced was Anopheles gambiae, the vector for Plasmodium parasites that cause malaria. Further mosquitoes have followed: Aedes aegypti (yellow fever and dengue fever vector) and Culex pipiens (lymphatic filariasis and West Nile fever). Species that are currently in sequencing include the body louse Pediculus humanus (Typhus vector), the triatomine Rhodnius prolixus (Chagas disease vector) and the tick Ixodes scapularis (Lyme disease vector). The motivations for sequencing vector genomes are to further understand vector biology, with an eye on developing new control strategies (for example novel chemical attractants or repellents) or understanding the limitations of current strategies (for example the mechanism of insecticide resistance); to analyse the mechanisms driving their evolution; and to perform an exhaustive analysis of the gene repertory. The proliferation of genomic data creates the need for efficient and accessible storage. We present VectorBase, a genomic resource centre that is both involved in the annotation of vector genomes and act as a portal for access to the genomic information (http://www.vectorbase.org).