对Dicer核糖核酸酶的卡斯巴酶依赖转化为促进死亡的脱氧核糖核酸酶
Akihisa Nakagawa1, Yong Shi, Eriko Kage-Nakadai
1Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA.
概括
这项研究揭示,Dicer (DCR-1) 是一种对于小RNA处理至关重要的酶,在C. elegans的亡过程中也会碎片化DNA. 卡斯巴酶介导的裂变将DCR-1转化为脱氧核糖核酶,保持DNA降解途径.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 染色体碎片化是物种间亡的一个关键事件.
- 在哺乳动物中,caspases通过抑制核酶来触发这种碎片化.
研究的目的:
- 为了研究Caenorhabditis elegans Dicer (DCR-1) 在亡性染色体分裂中的作用.
- 为了阐明在亡过程中卡斯帕斯介导的DNA降解的机制.
主要方法:
- 在C. elegans中对dcr-1的基因失活.
- 对亡和染色体碎片化的分析.
- 生物化学测试以确定核酶活性.
主要成果:
- dcr-1 失活导致细胞亡,并阻断了染色体的分裂.
- CED-3酶分裂了DCR-1,产生了具有脱氧核糖核酶活性的C端片段.
- 这个DCR-1片段诱导了3'基DNA断裂,促进了亡.
结论:
- 通过酶介导的DNA降解的激活在亡中得到保存.
- DCR-1 扮演着双重的角色:小RNA 处理和染色体DNA 在亡过程中的分裂.
- 由蛋白酶介导的DCR-1从核糖核酶转化为脱氧核糖核酶是一个关键的监管步骤.
相关概念视频
Caspases
Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.
Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
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