Functional analysis of BmClock, BmCry-α, and BmCry-β, circadian clock genes found in the genome of the silkworm, Bombyx mori

家蚕基因组中发现的生物钟基因 BmClock、BmCry-α 和 BmCry-β 的功能分析

基本信息

批准号：
12460025
负责人：
SHIMADA Toru
金额：
$ 9.22万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12460025/
关键词：
Bombyx mori Circadian clock Photoperiodism EST Genome analysis Transcription factors Drosophila DNA microarray

项目摘要

An orthologue for clock (BmClock), a Drosophila circadian clock gene, was found in the Bombyx mori EST database. The nucleotide sequence of the BmClock cDNA was determined. The full length cDNA was 7521 bp in length and encoded a putative 585 amino acid sequence, which contained three conserved domains, a basic helix-loop-helix, PAS-1, and PAS-2. BmClock mRNA was expressed with circadian rythmicity, and the mRNA peak was observed in the evening.We also found an orthologue (BmCry-α) of mammalian cryptochrome genes in the B. mori EST database. The cDNA was 4509 bp in length and encoded a complete 730-amino acid protein. The aa sequence conserved the domains for binding to DNA, MTHF, and FAD, respectively. Another kind of cryptochrome-like sequence was also found in the ESTs, it was an orthologue of the Drosophila cryptochrome gene. The length of cDNA was 1587 bp. It encoded 308 amino acid residues. RT-PCR analyzes of the brains demonstrated that both two chryptochrome mRNAs are expressed in a circadian fashion, and their peak appeared in the night. Another kind of cryptochrome (BmCry-γ) has just been found i as an EST. Additionally a member of the DNA 6-4 photolyase gene family (including cryptochromes) was found.The cDNA microarray was utilized to find circadian rhythm in the larval fat body of B. mori. We found 11 genes that expressed mRNAs in the circadian fashion. On the other hand, we also did a crossing experiment between a polyvoltine strain and a bivoltine strain, and found that not only sex-linked gene but also autosomal gene(s) regulates the photoperiodism.

在家蚕EST数据库中发现了时钟(BmClock)的直系同源物。确定了BmClock cDNA的核苷酸序列，全长cDNA长度为7521bp，编码假定的585个氨基酸序列。，其中包含三个保守结构域、基本螺旋-环-螺旋、PAS-1 和 BmClock mRNA。表达具有昼夜节律性，mRNA峰值出现在晚上。我们还在家蚕EST数据库中发现了哺乳动物隐花色素基因的直系同源物（BmCry-α），其cDNA长度为4509 bp，编码完整的730-α。氨基酸蛋白中还发现了另一种类似隐花色素的序列。 ESTs，它是果蝇隐花色素基因的直系同源物，其编码308个氨基酸残基，其大脑的RT-PCR组合证明这两种隐花色素mRNA以昼夜节律方式表达。另一种隐花色素（BmCry-γ）刚刚被发现，也是 DNA 6-4 的成员。发现了光裂解酶基因家族（包括隐花色素）。利用cDNA微阵列发现了家蚕幼虫脂肪体中的昼夜节律。另一方面，我们也做了一个以昼夜节律方式表达mRNA的基因。多化株与二化株的杂交实验发现，不仅有性连锁基因，还有常染色体基因对光周期的调节。