As an initial step to define the molecular mechanism of initiation and termination of diapause during the embryogenesis of silkworms, Bombyx mori, mRNA transcripts from maintained and activated diapause eggs were compared with differential expression using cDNA array. Twenty-four individual cDNA transcripts were expressed differentially in a total of 1,468 different cDNAs. Among those clones, mRNA transcript from cytochrome oxidase subunit I (COI), which was detected to be 2-kb transcripts, gradually increased in diapause-activated eggs during early embryogenesis. Further analysis revealed that mRNA transcripts from silkworm COI were highly expressed in testis, fat body, and midgut during the larval stage. These results may indicate that the expression of silkworm COI mRNA is regulated developmentally as well as tissue-specifically.
(c) 2005 Wiley-Liss, Inc.