在裂变酵母中,由Myb-domain蛋白调节端粒长度和功能
J P Cooper1, E R Nimmo, R C Allshire
1Howard Hughes Medical Institute, Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309, USA.
Nature
|February 20, 1997
概括
Taz1p是一种新型的裂变酵母端粒蛋白,对于调节端粒长度和基因表达至关重要. 它的缺失导致显著延长的端粒和受损的半径变化.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 端粒是真核染色体上的保护帽,对复制和基因组稳定性至关重要.
- 端粒长度调节在瘤发生研究中至关重要.
- 已知的端粒结合蛋白包括芽生长酵母中的Rap1p和人类中的hTRF,但hTRF的功能仍然不清楚.
研究的目的:
- 在裂变酵母中识别和表征新的端粒相关蛋白质.
- 调查Taz1p在端粒长度调节,基因表达和半变的功能.
主要方法:
- 在裂变酵母 (Schizosaccharomyces pombe) 中进行基因选,以识别与端粒相关的蛋白质.
- 基因破坏和删除已识别的taz1+基因.
- 对端粒长度,端粒相邻基因表达和介质进展的分析.
主要成果:
- 鉴定Taz1p,一种与人类hTRF同源的裂变酵母蛋白,共享MybDNA结合域.
- 破坏taz1+基因导致端粒长度显著增加.
- Taz1p对于抑制端粒附近的基因转录和正常介质过程至关重要.
结论:
- 在裂变酵母中,Taz1p在维持端粒长度恒温中起着至关重要的作用.
- Taz1p作为端粒长度的负调节剂,可能通过抑制端粒酶活性或端粒酶独立的延长通路而起作用.
- 塔兹1p还参与调节端粒近端区域的基因表达,对于适当的介质功能是必要的.
相关概念视频
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In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded DNA.


