KLF7通过抑制缺氧诱导因子1α转录影响肉鸡脂肪组织发育  

KLF7 Affects Development of Broiler Adipose Tissue by Inhibiting Hypoxia-Inducible Factor 1 Alpha Transcription

作　　者：金钊 邵淑丽 谭茗 李金炜 贾炳豪 王维禹 周瑶 崔婷婷 孙婴宁 JIN Zhao;SHAO Shu-Li;TAN Ming;LI Jin-Wei;JIA Bing-Hao;WANG Wei-Yu;ZHOU Yao;CUI Ting-Ting;SUN Ying-Ning(Department of Biotechnology,College of Life Science and Agriculture Forestry,Qiqihar University,Qiqihar 161006,Heilongjiang,China)

机构地区：[1]齐齐哈尔大学生命科学与农林学院生物技术系,黑龙江齐齐哈尔161006

出　　处：《中国生物化学与分子生物学报》2021年第3期363-371,共9页Chinese Journal of Biochemistry and Molecular Biology

基　　金：国家自然科学基金(No.31402061);黑龙江省自然科学基金(No.YQ2019C025);2018年度黑龙江省省属高等学校基本科研业务费科研项目(植物性食品加工技术特色学科专项)(No.YSTSXK201875);2019年齐齐哈尔大学研究生创新科研项目(No.YJSCX2019051)资助。

摘　　要：Krüppel样转录因子7(Krüppel-like factor 7,KLF7)是脂肪形成的负调控因子,而缺氧诱导因子1(hypoxia-inducible factor 1,HIF1)促进缺氧诱导的哺乳动物脂肪组织发育。本实验室前期利用ChIP-seq技术,发现在鸡的缺氧诱导因子1α(hypoxia-inducible factor 1 alpha,HIF1α)基因上游存在1个KLF7的结合峰,提示KLF7可能调控HIF1α基因转录。为此,本研究首先利用ChIP-PCR技术验证ChIP-seq结果,发现KLF7能够与HIF1α基因5′侧翼区结合。双荧光素酶报告基因与qRT-PCR结果显示,过表达KLF7能够显著下调HIF1α(-4432/-4182)的荧光素酶报告基因活性(P<0.01),抑制HIF1α基因表达。与野生型质粒相比,将生物信息学预测的KLF7结合基序"TGCGCAGCAA"(-4300/-4290)缺失突变后,HIF1α(-4432/-4182)报告基因活性显著增强(P<0.01)。此外,选取第19代1~7周龄东北农业大学高、低脂双向选择品系肉鸡(Northeast Agricultural University broiler lines divergently selected for abdominal fat content,NEAUHLF)作为实验材料,利用qRT-PCR检测HIF1α基因在肉鸡腹部脂肪组织中的表达规律。结果显示,HIF1α在1~7周龄高脂系肉鸡中的相对表达量均高于低脂系,提示HIF1α对鸡脂肪组织发育具有促进作用。在永生化鸡前体脂肪细胞系(immortalized chicken preadipocyte cell line,ICP1)诱导分化过程中,HIF1α相对表达量逐渐升高。综上所述,HIF1α是转录因子KLF7的一个靶基因,KLF7可能通过抑制HIF1α基因转录参与鸡脂肪组织发育过程。Krüppel-like factor 7(KLF7)is a negative regulator of adipogenesis,whereas hypoxia-inducible factor 1(HIF1)promotes anoxic-induced adipose tissue development in mammals.Our previous ChIP-seq analysis showed that one of the KLF7 binding peaks was present upstream of hypoxia-inducible factor 1 alpha(HIF1α),indicating that KLF7 may regulate HIF1αtranscription.For this purpose,ChIP-PCR was used to verify ChIP-seq results,which showed that KLF7 directly bound to the HIF1αupstream region.Dual luciferase reporter and qRT-PCR results showed that KLF7 overexpression significantly decreased the luciferase reporter activity of HIF1α(-4432/-4182)(P<0.01)and inhibited HIF1αexpression.After the deletion of KLF7 binding motif"TGCGCAGCAA"(-4300/-4290)predicted by bioinformatics,the luciferase reporter activity of HIF1α(-4432/-4182)was significantly enhanced compared with wild-type plasmid(P<0.01).Furthermore,Northeast Agricultural University broiler lines divergently selected for abdominal fat content(NEAUHLF)at the age of 1-7 weeks from the 19th generation were selected as experimental materials.qRT-PCR was used to detect the expression of HIF1αin the abdominal adipose tissue of broilers.The results showed that the relative HIF1αexpression was higher in fat line than in lean line at 1-7 weeks of age,indicating that HIF1αpromotes the adipose tissue development of broilers.The relative expression of HIF1αincreased gradually during the induction of differentiation of immortalized chicken preadipocyte cell line(ICP1).Taken together,HIF1αis a direct target gene of transcription factor KLF7.KLF7 may inhibit chicken adipose tissue development by repressing HIF1αtranscription.

关 键 词：鸡 Krüppel样转录因子7 缺氧诱导因子1Α 转录 脂肪组织 

分 类 号：S831.2[农业科学—畜牧学]