湖羊转录因子CTCF基因序列分析及其对NR5A1基因转录活性的调控

Sequence analysis of transcription factor CTCF and its regulation on transcription activity of NR5A1 gene in Hu sheep

转录因子CTCF在动物生长发育过程中发挥重要的调控作用,但其在绵羊中的序列特征、组织器官表达及功能目前尚不清楚。本研究以湖羊CTCF基因为研究对象,采用PCR方法克隆获得其编码区全序列,发现其序列全长2187 bp,编码727个氨基酸残基,含有11个连续的锌指结构域。组织器官表达谱分析发现CTCF基因在湖羊各个组织器官中广泛表达,在子宫中表达量相对较低,在胃中表达量相对较高。JASPAR在线软件预测发现核受体NR5A1基因内含子(翻译起始位点ATG前393 bp片段)含有3个CTCF结合位点,双荧光素酶试验结果显示,CTCF结合位点突变后NR5A1基因转录活性显著或极显著下降,表明CTCF可能通过调控NR5A1基因转录参与调控湖羊繁殖性能。

Transcription factor CTCF plays an important regulatory role in growth and development of animals,but its sequence characteristics,tissues and organs expression and function in sheep are still unclear.In this study,CTCF gene of Hu sheep was used as research object,the full coding sequence of CTCF was cloned by RT-PCR.The result showed that the full-length sequence of CTCF was 2187 bp,encoding 727 amino acids and containing 11 consecutive zinc finger domains.CTCF gene was widely expressed in various tissues and organs of Hu sheep,with a relatively low expression in uterus and a relatively high expression in stomach.Predication results showed that the intron(the 393 bp fragment before translation initiation site ATG)of nuclear receptor NR5A1 gene contained three CTCF binding sites by the JASPAR online software.The results of dual luciferase assay showed that the transcription activity of NR5A1 gene decreased significantly or extrenely significantly when the CTCF binding sites were mutated,indicating that CTCF participated in the regulation of reproductive performance of Hu sheep by regulating NR5A1 gene transcription.