新酵母アクチンのような遺伝子は,細胞サイクル後半に必要とされる
1Laboratoire de Biochimie, Centre National de la Recherche Scientifique, Strasbourg, France.
Nature
|January 9, 1992
まとめ
研究者らは,細胞成長に不可欠なアクチンのようなタンパク質をコードする新しい酵母遺伝子であるACT2を発見した. アクチンと47%同一のこのタンパク質は,細胞骨格の再編成において役割を果たし,真核生物におけるアクチンのようなタンパク質の保存された機能を強調しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- アクチンは,運動性と分裂のような真核細胞機能に不可欠な,高度に保存された細胞骨格タンパク質です.
- 酵母Saccharomyces cerevisiaeは,細胞組織と分極化した成長に不可欠なアクチン遺伝子 (ACT1) を持っています.
- 以前の研究は,高度に保存されたアクチンタンパク質に焦点を当て,異なるアクチンのような分子に関する知識は限られていた.
研究 の 目的:
- 新しく特定された酵母遺伝子ACT2とその暗号化されたタンパク質を特徴づけるため.
- Act2タンパク質の機能と構造特性を調査する.
- ユカリオットの異なるアクチンのようなタンパク質の進化的意義を探求する.
主な方法:
- Saccharomyces cerevisiaeにおけるACT2の遺伝子識別と特徴付けについて.
- タンパク質配列分析と,既知のアクチン構造との比較.
- Act2が既知のアクチン3D構造に構造的に重ねられている.
- 酵母菌の植物性成長のためのACT2遺伝子要件の評価.
主要な成果:
- ACT2の発見,酵母分裂遺伝子で,酵母アクチンとの47%の同一性を持つ391アミノ酸タンパク質 (Act2) をコードする.
- Act2タンパク質は,ポリメリゼーションと結合に欠かせないループの有意な差異を示し,コアドメインは保持されています.
- ACT2は酵母細胞の植物性成長に不可欠です.
- アクチンのようなタンパク質に関する関連遺伝子は,他の真核生物にも存在し,機能が保存されていることを示唆しています.
結論:
- Act2タンパク質は,最初に記述された高度に異なったアクチン分子を表しています.
- 構造的および生理学的データは,Act2が細胞周期中の細胞骨格の再編成に役割を果たすことを示唆しています.
- ACT2とその保存された同類体の発見は,カノニカルなアクチンを超えてアクチンのようなタンパク質の重要性を強調しています.
関連する概念動画
Yeast Signaling
Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
Negative Regulator Molecules
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
Cells Coordinate Growth and Proliferation
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
The Contractile Ring
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
Actin Polymerization and Cell Motility
Actin is a family of globular proteins that are highly abundant in eukaryotic cells. It makes up approximately 1-5% of total cell protein concentration. Actin monomers polymerize to form a complex network of polarized filaments, the actin cytoskeleton, that plays a crucial role in many cellular processes, including cell motility, division, endocytosis, and metastasis of cancer cells.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
Gene Regulation During Sporulation
Sporulation is a complex developmental process that allows certain Gram-positive bacteria, such as Bacillus subtilis and Clostridium species, to survive extreme environmental conditions. This process is tightly regulated by a series of signaling cascades and transcriptional controls, ensuring the formation of a highly resistant endospore.Sporulation is triggered by unfavorable conditions, such as nutrient depletion, and is governed by a phosphorelay system. One of the sensor kinases, such as...


