An analysis of the Athetis lepigone transcriptome from four developmental stages

Athetis lepigone Möschler (Lepidoptera: Noctuidae) has recently become an important insect pest of maize (Zea mays) crops in China. In order to understand the characteristics of the different developmental stages of this pest, we used Illumina short-read sequences to perform de novo transcriptome assembly and gene expression analysis for egg, larva, pupa and adult developmental stages. We obtained 10.08 Gb of raw data from Illumina sequencing and recovered 81,356 unigenes longer than 100 bp through a de novo assembly. The total sequence length reached 49.75 Mb with 858 bp of N50 and an average unigene length of 612 bp. Annotation analysis of predicted proteins indicate that 33,736 unigenes (41.47% of total unigenes) are matches to genes in the Genbank Nr database. The unigene sequences were subjected to GO, COG and KEGG functional classification. A large number of differentially expressed genes were recovered by pairwise comparison of the four developmental stages. The most dramatic differences in gene expression were found in the transitions from one stage to another stage. Some of these differentially expressed genes are related to cuticle and wing formation as well as the growth and development. We identified more than 2,500 microsatellite markers that may be used for population studies of A. lepigone. This study lays the foundation for further research on population genetics and gene function analysis in A. lepigone.