O-GlcNAc转移酶催化HCF-1的特定位点蛋白解
Francesca Capotosti1, Sophie Guernier, Fabienne Lammers
1Center for Integrative Genomics, University of Lausanne, Switzerland.
Cell
|February 8, 2011
概括
与O相关的β-N-乙糖胺转移酶 (OGT) 酶直接分裂并修改细胞循环的关键调节者HCF-1蛋白. 这种OGT活动对于HCF-1的成熟及其在细胞分裂中的作用至关重要.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 人类HCF-1蛋白是一种表观遗传调节器,对细胞循环控制至关重要.
- HCF-1经过蛋白质分解成熟,产生N-终端 (HCF-1(N)) 和C-终端 (HCF-1(C)) 子单元.
- 在HCF-1(PRO) 重复时的蛋白质分解裂变对于M阶段的HCF-1(C) 功能至关重要.
研究的目的:
- 研究O链 β-N-乙糖胺转移酶 (OGT) 在HCF-1成熟中的作用.
- 阐明OGT影响HCF-1蛋白解处理和细胞循环调节的机制.
主要方法:
- 研究了OGT和HCF-1 (PRO) 重复序列之间的相互作用.
- 评估了OGT.通过HCF-1 (N) 的O-GlcNAcylation.
- 分析了替换HCF-1(PRO) 重复用替代裂解信号对HCF-1功能的影响.
主要成果:
- OGT 直接识别并分割 HCF-1 ((PRO) 重复序列.
- 通过OGT调解HCF-1 (N) 亚单元的O-GlcNAcylation,使得HCF-1 (N) 亚单元的O-GlcNAcylation得到调解.
- 用其他裂解信号替换HCF-1(PRO) 重复激活蛋白质分解,但不能激活HCF-1(C) 激活M阶段进展.
结论:
- 在HCF-1的蛋白质分解成熟过程中,OGT起着直接而重要的作用.
- 这项研究揭示了OGT介导的O-GlcNAcylation和HCF-1蛋白质分解处理之间的新联系.
- 这种联系对于HCF-1对细胞周期的适当调节至关重要.
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