线粒体膜重塑受保护的形蛋白酶调节
G Angus McQuibban1, Saroj Saurya, Matthew Freeman
1MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
Nature
|May 30, 2003
概括
酵母体的rhomboid,Rbd1p和Rbd2p,除了信号传递之外还有新的作用. 位于线粒体中的Rbd1p分裂Mgm1p,调节线粒体膜融合和细胞呼吸.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 分子遗传学 分子遗传学
背景情况:
- 状蛋白质是膜内血清蛋白质酶.
- 已知它们可以激活Drosophila. epidermal生长因子受体 (EGFR) 的信号传递.
- 在整个进化过程中被保存下来,状体很可能有超出EGFR信号传导的作用.
研究的目的:
- 为了研究Saccharomyces cerevisiae中rhomboid蛋白的功能.
- 为了识别酵母体,Rbd1p和Rbd2p的基质和细胞作用.
- 为了探索线粒体体的保存和功能.
主要方法:
- 酵母突变的基因删除和表型分析.
- 对Rbd1p.p的亚细胞局部化研究.
- Rbd1p基质的识别和特征.
主要成果:
- 麦片菌有两个圆形体:Rbd1p和Rbd2p.
- Rbd1p定位在线粒体内膜中,对呼吸至关重要.
- Rbd1p分裂细胞染色体c过氧化酶 (Ccp1p) 和Mgm1p,这是线粒体融合的关键调节者.
结论:
- 酵母体Rbd1p通过Mgm1p裂变在线粒体膜重塑中发挥着至关重要的作用.
- 圆柱体的内膜蛋白解调节了超出信号的细胞过程.
- 线粒体体在功能上是保存的,哺乳动物的PARL拯救了酵母突变.
相关概念视频
Mitochondrial Membranes
A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
The Inner Mitochondrial Membrane
The inner mitochondrial membrane is the primary site of ATP synthesis. The inner membrane domain that forms a smooth layer adjacent to the outer membrane is called the inner boundary membrane. This domain contains membrane transporters that drive metabolites in and out of the mitochondria. In contrast, the inner membrane network that invaginates into the matrix space is called the cristae membrane. This domain accounts for principle mitochondrial function as it accommodates the protein...
Mitochondrial Protein Sorting
Mitochondria are double-membrane organelles of the eukaryotes involved in cellular metabolism, signaling, ATP synthesis, and programmed cell death. Each of these processes requires specific proteins and enzymes that must be correctly sorted to the right mitochondrial subcompartment for the proper functioning of the organelle.
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Mitochondrial Precursor Proteins
Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70 chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial precursors...
Most of the mitochondrial precursors...
Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Mitochondrial Membranes
A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...


