发育调节的线粒体融合由保存的,新的,预测的GTPase调节
1Department of Genetics, Stanford University School of Medicine, California 94305, USA.
Cell
|July 11, 1997
概括
模糊洋 (fzo) 基因对于Drosophila.的线粒体融合至关重要. fzo中的突变破坏了这一过程,导致由于精子发育缺陷而导致男性不育.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 遗传学是一种遗传学.
- 发展生物学 发展生物学
背景情况:
- 线粒体融合对于细胞功能和发育至关重要.
- 调节线粒体融合的机制,特别是在精子等特殊细胞中,尚未完全理解.
研究的目的:
- 为了识别和描述Drosophila精子生成期间线粒体融合的蛋白质媒介.
- 调查线粒体动力学中模糊洋 (fzo) 基因的功能和调节.
主要方法:
- 在Drosophila melanogaster.中fzo基因突变的分析.
- 在正在发育的精子虫中对Fzo蛋白的局部化研究.
- 研究突变对GTP结合域的影响.
主要成果:
- 德洛索菲拉fzo基因编码了一种新型的跨膜GTPase,它对于精子的线粒体融合至关重要.
- fzo突变雄性表现出缺陷的线粒体融合,并且是无菌的.
- 在融合过程中,Fzo蛋白定位到线粒体,并通过GTP结合来调节.
结论:
- Fzo是第一个确定了线粒体融合的蛋白质媒介.
- 在Drosophila的功能性精子的发展中,Fzo起着至关重要的作用.
- 在其他生物体中存在Fzo的同类物,这表明在线粒体融合中保留了作用.
相关概念视频
GTPases 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...
Large G-proteins, also known...
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...
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,...
Energy to Drive Translocation
Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
Generally, polypeptides are unfolded by two distinct...
Generally, polypeptides are unfolded by two distinct...
GTPases 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...
Large G-proteins, also known...
Rab Cascades
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.


