関連する実験動画
Updated: Jul 29, 2026

10:52
Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
セントロソーム内のガンマチューブリンを含むリングによるマイクロチューブルの核形成
M Moritz1, M B Braunfeld, J W Sedat
1Department of Biochemistry & Biophysics, University of California at San Francisco 94143-0448, USA.
Nature
|December 7, 1995
まとめ
センターソームはセンターソームです.
科学分野:
- 細胞生物学 細胞生物学
- 細胞骨格のダイナミクス
- 分子細胞生物学 分子細胞生物学
背景:
- 動物細胞の微小管の組み立てには,セントリオールとペリコントリオール物質 (PCM) で構成されたセンターソームが必要です.
- PCMは,微小管の核形成を開始するために不可欠です.
- ガンマチューブリンは,マイクロチューブルの核形成に関与する唯一の知られているPCM成分です.
研究 の 目的:
- マイクロチューブルの核形成過程でセンターソーム内のガンマチューブリン構造的局所化を調査する.
- マイクロチューブルの核形成部位の形成におけるガンマチューブリンの役割を解明する.
主な方法:
- 免疫電子顕微鏡トモグラフィーは,浄化されたセンターソームに用いられました.
- セントロソームは微小管と微小管なしの両方で分析され,ガンマチューブリン局所化を観察しました.
主要な成果:
- ガンマチューブリンは,孤立したセンターソームの周心状物質内の環状構造に観察されました.
- 微小管の成長の核化により,ガンマチューブリンが新たに形成された微小管のマイナス端に局所化します.
結論:
- セントロソームのPCMの微小管核形成部位は,環状に構成されています.
- これらの環状構造には,ガンマチューブリンが複数のコピーを含んでおり,マイクロチューブルの核形成のテンプレートとして機能しています.
関連する概念動画
Microtubules
There are three types of cytoskeletal structures in eukaryotic cells—microfilaments, intermediate filaments, and microtubules. With a diameter of about 25 nm, microtubules are the thickest of these fibers. Microtubules carry out a variety of functions that include cell structure and support, transport of organelles, cell motility (movement), and the separation of chromosomes during cell division.Microtubules are hollow tubes whose walls are made up of globular tubulin proteins. Each tubulin...
Microtubules
Microtubules are the thickest cytoskeletal filaments with a diameter of 25 nm. In prokaryotic organisms, microtubules are commonly found in locomotory appendages like cilia and flagella. In eukaryotic cells, microtubules form specialized extensions for moving fluid over the surface, like those found in cells lining the intestine.
Microtubules have two structurally similar globular protein subunits: α and β tubulins. In the cytosol, the α and β tubulins form a heterodimer. These αβ-heterodimers...
Microtubules have two structurally similar globular protein subunits: α and β tubulins. In the cytosol, the α and β tubulins form a heterodimer. These αβ-heterodimers...
Microtubule Formation
Microtubules are dynamic structures that undergo continuous assembly and disassembly. They originate from specialized multi-protein complexes known as microtubule organizing centers or MTOCs. Within the MTOC, the point of origin of the microtubule is known as the minus end, while the end radiating outward is the plus end. Microtubules serve two primary functions — the organization of spindle complexes to separate sister chromatids during mitotic or meiotic cell division and the formation of...
Microtubule Instability
Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated assembly and...
Spindle Assembly
Spindle assembly occurs through three, often coexisting, pathways – the centrosome-mediated pathway, the chromatin-mediated pathway, and the microtubule-mediated pathway – collectively contributing to form a robust spindle apparatus.
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a microtubule array...
In most cells, centrosomes are the primary microtubule nucleation centers. In the centrosome-mediated pathway, the G2-prophase transition triggers centrosome maturation and increased microtubule nucleation. Progressive nucleation results in a microtubule array...
Centrioles and Centrosomes
Most animal cells comprise a pair of centrioles together called a centrosome. The cell duplicates its centrosome and contains two centrosomes side-by-side, which begin to move apart during the prophase. As the centrosomes migrate to two different sides of the cell, microtubules start extending from each centrosome toward the other end. The mitotic spindle is composed of the centrosomes and their emerging microtubules.
Near the end of the prophase, also called late prophase or "prometaphase,"...
Near the end of the prophase, also called late prophase or "prometaphase,"...

