Solexa sequencing based transcriptome analysis of Helicoverpa armigera larvae

Helicoverpa armigera (Hubner) is a polyphagous Lepidoptera pest which causes great economic losses in crop production worldwide. In contrast to its agricultural importance, advances in the molecular aspects of this insect are quite limited. In the present study, Illumina's SOLEXA sequencing was adopted to determine the transcriptome of young H. armigera larvae. About 7 gigabases of raw sequence data was generated and assembled into 116,601 contigs with an average length of 389 base pairs after data preprocess. 37,352 of these contigs were annotated by searching against Uniref 100 of UniProt database. The annotated sequences were functionally classified into three groups including biological process (15,632 sequences), cellular component (9,562 sequences) and molecular function (19,258 sequences). KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis showed that 1,409 contigs predicted to encode enzymes with enzyme commission numbers were mapped into 220 KEGG pathways in total. Finally, contigs with simple sequence repeats were derived from this dataset.