人类环林E与周期性G1-S相蛋白激酶的关联
1Department of Molecular Biology, Scripps Research Institute, La Jolla, CA 92037.
Science (New York, N.Y.)
|September 25, 1992
概括
人类环林E蛋白及其激酶活性对于细胞周期中的G1到S相过渡至关重要. 环林E-Cdk2复合体作为关键调节剂,在G1后期和S早期阶段达到峰值.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- G1环林调节了Saccharomyces cerevisiae中的G1到S阶段的过渡.
- 循环素E通过对人类cDNA的选来确定,这些DNA补充了G1循环素缺乏的芽酵母.
研究的目的:
- 研究人类环林E在细胞循环调节中的作用.
- 描述环林E及其酶的活性和细胞周期关联.
主要方法:
- 在酵母中对人类cDNA的功能查.
- 在整个人类细胞周期中分析环林E蛋白水平和相关的激酶活性.
- 鉴定环林E-Cdk2复合物.
主要成果:
- 人类环林E拯救了酵母中的G1环林缺乏.
- 循环E蛋白和相关的激酶活性在细胞周期期间呈现周期性波动.
- 环林E和激酶活性的峰值水平发生在G1晚期和S早期阶段.
- 环素E与Cdk2形成复合体,表现出相关的激酶活性.
结论:
- 环林E-Cdk2复合体是人类G1-S阶段特定的调节蛋白激酶.
- 环素E在细胞周期从G1到S阶段的进展中起着保留的作用.
相关概念视频
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02:14GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
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01:22Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...