EST Analysis of Gene Expression in the Germ-Layer Formation Stage of the Bombyx mori

다국어 초록 (Multilingual Abstract)

In order to explore the gene expression underlying early embyogenesis, expressed sequence tag (EST) analysis was conducted using a cDNA library made from the 24h embryo of a silkworm, Bombyx mori. A total of 8,928 clones were screened plasmid with cDNA insert and have partially sequenced the 5´ ends to generate 2,446 assembled sequences. The annotation of 2,446 high-quality ESTs by a BLAST search, revealed that 1,516 (62％) of the sequences represented known genes. Over 2,400 ESTs consisted of 1,568 single ESTs (singlets) and 878 redundant ESTs (contigs). The functional groups of those sequences with matches in the database (P＜E-4) were constructed according to their putative molecular functions, biological process and cellular components. Seventy-five potential clones, associated with cell communication and development of the biological process, were selected in order to analyze their expression patterns by dot-blot assay. Most of them showed a predominant expression in the expected 24h embryo, the germ-layer formation stage. This study should provide information about the overall gene expression profiles of the Bombyx mori early embryo.