Studies on the transcriptional regulatory factors controlling the expression of hCG and LH gene

控制hCG和LH基因表达的转录调控因子的研究

• 批准号: 03670785
• 负责人: KATAYAMA Kazuaki
• 金额: $ 1.28万
• 依托单位: Kobe University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03670785/
• 关键词: hCGbeta gene; LHbeta gene; trophoblast; footprint assay; gel shift assay; hCGβ; 転写制御因子; LHβ

The hCGb subunit is encoded by a cluster of six genes (or pseudogenes). Linked to this cluster is the single gene encoding the related LHbeta subunit. The general structure of these genes is very similar. hCGbeta genes are expressed mainly in first trimester placenta and LHbeta gene is expressed in pituitary gland. In this project, we tried to elucidate what factors control the tissue and stage specific expression of hCGbeta gene and LHbeta gene. Promoter region of these genes were isolated and used for footprint assays and gel shift assays. Although the footprint protection pattern of the hCGbeta gene fragment and LHbeta gene fragment using trophoblastic nuclear extract was very similar, there was a region LHbeta was protected but hCGbeta was not protected. Gel shift assays showed the factor which binds to the region was expressed in tissues except pituitary. It suggests that the factor suppresses expression of LHbeta gene. In vitro mutagenesis to make LHbeta promoter mutants substituted with the hCGbeta nucleotide sequence was made to analyze key sequences to acquire activity in trophoblasts.We also performed footprint assays of hCGbeta gene using trophoblastic nuclear extracts from various stage of pregnancy. They did not show marked difference. Probably there are many nuclear factors binding to the same domain and it is hard to detect change of some factors.To know the difference of the active hCGbeta gene and inactive hCGbeta gene, upstream sequence of hCGbeta gene 5 and hCGbeta gene 7 were used for footprint assays. We could not detect visible change of the protection pattern. It suggests that there may be factors we cannot detect by footprint assay.The information obtained here provides a foundation for further studies on nuclear factors binding to this region regulating hCGbeta gene and LHbeta gene.

hCG b亚基由六个基因（或假基因）的簇编码。与这个簇相连的是编码相关LH β亚基的单个基因。这些基因的一般结构非常相似。hCG β基因主要表达于孕早期胎盘，LH β基因主要表达于垂体。本研究试图阐明什么因素控制hCG β基因和LH β基因的组织特异性和阶段特异性表达。分离这些基因的启动子区域并用于足迹测定和凝胶迁移测定。虽然使用滋养层细胞核提取物的hCG β基因片段和LH β基因片段的足迹保护模式非常相似，但存在LH β受保护而hCG β不受保护的区域。凝胶迁移分析表明，该区域结合的因子在除垂体外的组织中表达。提示该因子抑制LH β基因表达。通过体外突变使LH β启动子突变体被hCG β核苷酸序列取代，以分析在滋养层细胞中获得活性的关键序列，并使用妊娠不同阶段的滋养层细胞核提取物进行hCG β基因足迹分析。他们没有表现出明显的差异。为了解活性hCG β基因和非活性hCG β基因的差异，采用hCG β基因5和hCG β基因7的上游序列进行足迹分析。我们无法检测到保护模式的可见变化。这一结果为进一步研究与该区域结合的核因子对hCG β基因和LH β基因的调控作用提供了基础。

项目成果

Yamaguchi Y.et al: "Studies on Placental Alkaline Phosphatase Gene Expression" Adv Obstet Gynecol. 44. 239-244 (1992)

Yamaguchi Y.et al：“胎盘碱性磷酸酶基因表达的研究”Adv Obstet Gynecol。

大谷 徹郎,望月 眞人: "胎盤ホルモンの遺伝子ーhCG遺伝子を中心としてー" 産婦人科の実際. 40. 603-606 (1991)

Tetsuro Otani，Masato Mochizuki：“胎盘激素基因 - 关注 hCG 基因”妇产科实践 40. 603-606 (1991)。