家蚕滞育的分子机理2.蛹期滞育激素基因的表达与滞育决定

Molecular Mechanism of Diapaues in Bambyx mori2.Diapause Determination and Expression of Diapause Hormone Gene in Pupal Stage

滞育激素是由食道下神经节分泌的重要昆虫神经肽，诱导昆虫的滞育。选择具有ＲＮＡ聚合酶能够识别的启动子的质粒载体，将滞育激素ｃＤＮＡ克隆进去，在体外大量合成单一的滞育激素ｃＲＮＡ为参照，测定食道下神经节分泌滞育激素ｍＲＮＡ量来确定滞育激素的分泌量。结果证明食道下神经节分泌的滞育激素的数量决定昆虫的滞育。

mbryonic diapause in Bombyx is induced by diapause hormone(DH),which isproduced in the suboesophageal ganglion from a precursor protein.We have clonedthe DH cDNA into pBluescript KS vector that containing T7 RNA promoter can beused to synthesize nonspecific RNA.DH cRNA was synthesized and used as internalcontrol.We quantitatively measured DH mRNA at SG of day 3 pupae by Northemhybridization analysis and suggested that the embryonic diapause of Bombyx in nextgeneration was determined by DH mRNA content in SG.