title: Cloning of a B-type cyclin homolog from Bombyx mori and the profiles of its mRNA level in non-diapause and diapause eggs.
abstract: To understand the molecular mechanism of G2-arrest of cell division in embryonic diapause of the silkworm, Bombyx mori, we have cloned a cDNA encoding a Bombyx homolog of B-type cyclin. Levels of Bm cyclin-B mRNA were examined during diapause stage and early embryogenesis. The results showed that this G2-arrest did not always correspond to lowered transcriptional levels of cyclin-B, and that the mRNA accumulated in oocytes began to be degraded during the first hour after oviposition, i.e. the first meiosis, suggesting that the penetration of sperm triggered the degradation of maternal cyclin-B mRNA.
authors.affiliation: Laboratory of Sericulture and Entomoresources, School of Agricultural Sciences, Nagoya University, Chikusa, Nagoya 464-01, Japan, , , , , , JP.
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Niimi
authors.forename: H
authors.initials: H
authors.lastname: Ichimura
authors.forename: T
authors.initials: T
authors.lastname: Sasaki
authors.forename: O
authors.initials: O
authors.lastname: Yamashita
authors.forename: T
authors.initials: T
authors.lastname: Yaginuma