Abstract

White egg 2 is one of white egg mutants in silkworm, whose molecular mechanism remains unknown so far. In order to obtain an overall view on gene expression profiles at early embryo development stages, the white egg 2 near-isogenic line was constructed and the whole-genome of silkworm microarray system containing 21375 predicted genes from the silkworm whole genome sequence was employed to investigate gene expression profiles at 0, 24 and 48 h post oviposition between white egg 2 mutant and normal black egg strain. At 24 h post oviposition, 49 genes exhibited at least 2.0 fold differences at expression level, including 24 up-regulated genes and 25 down-regulated genes while at 48 h post oviposition, 52 genes, including 23 up-regulated genes and 29 down-regulated genes were expressed differentially over 2.0 change fold. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that nine differentially expression genes were involved in nine significant (p<0.05) pathways at 24 h post oviposition and 24 significant pathways at 48 h post oviposition, respectively. These pathways were related to amino acid metabolism, sugar metabolism, and series of major physiological metabolism. Our results hopefully shed light on the further study of molecular mechanism of white egg 2 mutant.

Key words: Bombyx mori, white egg 2 mutant, microarray, embryo, differentially expressed gene.