Coupled Expression of The Genes Encoding The Constituents of The Glycine Cleavage System in Chicken

编码甘氨酸裂解系统成分的基因在鸡中的耦合表达

基本信息

批准号：
62570101
负责人：
HIRAGA Koichi
金额：
$ 1.34万
依托单位：
Toyama Medical and Pharmaceutical 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：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62570101/
关键词：
coupled expression of the genes glycine decarboxylase cDNA H-protein cDNA glycine cleavage system 遺伝子の臓器特異的発現調節 H-蛋白cDNA 鶏ゲノムDNAライブラリーグリシン脱炭酸酵素遺伝子 H-蛋白遺伝子高グリシン血症

项目摘要

several clones of cDNA encoding qlycine decarboxylase, a constituent of the glycine cleavage system, were isolated from chicken liver cDNA expression libraries with a specific antibody. The overlapping cDNA clones evenly coded in an identical and open reading frame for the partial primary structures of the enzyme, and sequence of the 3,490 base long glycine decarboxylse cDNA was determined. H-protein cDNA was also cloned by immunoscreening, and this encoded the precursor from of chicken h-protein of 164 amino acid residues within the 840 base long cDNA sequence. Using both cDNA fragments we could analyze the mode of expression of the glycine decarboxylase and h-protein genes.Glycine decarboxylase mRNA aboundance varied in parallel with the content of the enzyme system in liver, kidney, and brain, which reveal specific activities of the overall reaction at a tatio of 35:11:1. in contrast, heart, spleen, and skeletal muscle mitochondria inactive in the reaction contained significant but small amounts of active H-protein and its mRNAs, whereas glycine decarboxylase and its mRNA were not found, indicationg that tissue-specific distribution of the enzyme system is primarily determined by expression of the hlycine decarboxylase gene. We defined them as the basal expression of the H-protein gene. Excluding the basal expression, relative efficiencies of run-off transcription on the glycine decarboxylase and H-protein genes appeared to be equal and the equimolar level of glycine decarboxylase and H-protein mRNAs are maintaianed in liver, kidney, and brain, irrespective of the difference in the amounts of expression of the genes. It is suggested that the magnitude of the glycine cleavage activity is specified by the coordinate mechanism which resides in regulation for biosynthesis of the components of the glycine cleavage system, except that the glycine decarboxylase gene expression alone is repressed in the cells of mesenchymal origin.

用特异性抗体从鸡肝 cDNA 表达文库中分离出编码甘氨酸脱羧酶（甘氨酸裂解系统的组成部分）的 cDNA 的几个克隆。重叠的 cDNA 克隆均匀地编码在酶的部分一级结构的相同且开放阅读框中，并确定了 3,490 个碱基长的甘氨酸脱羧酶 cDNA 的序列。还通过免疫筛选克隆了H蛋白cDNA，其编码了840个碱基长的cDNA序列内的164个氨基酸残基的鸡h蛋白的前体。使用这两个 cDNA 片段，我们可以分析甘氨酸脱羧酶和 h 蛋白基因的表达模式。甘氨酸脱羧酶 mRNA 丰度与肝、肾和脑中酶系统的含量平行变化，这揭示了总体的特定活性反应比例为35:11:1。相反，反应中不活跃的心脏、脾脏和骨骼肌线粒体含有大量但少量的活性 H 蛋白及其 mRNA，而未发现甘氨酸脱羧酶及其 mRNA，这表明酶系统的组织特异性分布是主要由甘氨酸脱羧酶基因的表达决定。我们将它们定义为 H 蛋白基因的基础表达。排除基础表达，甘氨酸脱羧酶和 H 蛋白基因的径流转录的相对效率似乎是相等的，并且甘氨酸脱羧酶和 H 蛋白 mRNA 在肝、肾和脑中保持等摩尔水平，无论基因表达量的差异。表明甘氨酸裂解活性的大小由协调机制指定，该协调机制存在于甘氨酸裂解系统组分的生物合成的调节中，除了在间充质来源的细胞中单独抑制甘氨酸脱羧酶基因表达之外。