摘要
胰岛素样生长因子(insulin-like growth factors,IGFs)系统对鱼类的生长和繁殖有着重要的作用。利用PCR方法克隆获得了鲤胰岛素样生长因子结合蛋白(insulin-like growth factor binding protein,IGFBP)-2和-3基因的上游启动子部分序列,长度分别是1142bp和1067bp。Igfbp-2启动子区域没有TATA框和CAAT框。同时,Igfbp-3中只含有TATA框,但没有CAAT框。研究结果表明,二者启动子不具备典型的启动子特征,同时,在二者启动子上还发现了cAMP应答元件和肝细胞核因子结合位点,以及Pit-1、Oct-1、RXR和GR等结合位点。研究认为,鲤Igfbp-2和-3基因的表达受到潜在的多因子调控。
Insulin-like growth factors（IGFs）system,including IGFs and IGF-binding proteins,plays a central role in growth and reproduction of fish and higher vertebrates.In serum and extracellular fluids,most circulating IGFs are bound to specific high affinity IGF-binding proteins（IGFBPs）that can protect them from degradation and modulate their actions.Common carp（Cyprinus carpio）is one of the most economically important fish in China.To improve the yield of common carp and get more economic benefits,the study of mechanism of growth and reproduction is very important.In the previous study,the cDNAs of common carp Igfbp-2 and-3 had been cloned,and the expression profiles and hormonal regulation were studied.The results showed that common carp Igfbp-2 and-3 mRNAs were expressed in many various tissues and different embryonic developmental stages,but the abundances were different significantly.To further understand the regulation mechanism of Igfbp-2 and-3,the study of their promoters is necessary.So,in this paper,the sequences of Igfbp-2 and-3 promoters were firstly cloned,and then the putative transcription binding sites were analyzed.The length of Igfbp-2 and-3 promoters we obtained was 1 142 bp and 1 067 bp,respectively.There was a consensus TATA box 22 bp 5＇ to the start site of transcription in Igfbp-3 promoter,while in the upstream there was a SP1 binding site instead of CAAT box.Neither TATA box nor CAAT box was found in the promoter of Igfbp-2,only a SP1 binding site and rich G/C motif in this region.These results showed that the promoters of common carp Igfbp-2 and-3 did not contain the characteristics of classic promoter.Furthermore,some other transcription binding sites were observed in the two promoters,such as CREB,HNF,Pit-1,Oct-1,RXR,GR,ER,PR,SRY and so on,while the STAT（signal transducer and activator of transcription）was only found in Igfbp-3.These results suggested that there were basic and hormone-inducible expression patterns of Igfbp-2 and-3 genes.However,the regulation mechanisms were n
出处
《水产学报》
CAS
CSCD
北大核心
2010年第10期1469-1477,共9页
Journal of Fisheries of China
基金
国家“九七三”重点基础研究计划(2004CB117402,2010CB126302)
国家自然科学基金项目(30671626)
广东省科技计划项目(2007B030300001)
关键词
鲤
胰岛素样生长因子结合蛋白
启动子
序列分析
Cyprinus carpio
insulin-like growth factor binding proteins
promoter
sequence analysis
