ミオブラストにおけるアルファアクチン遺伝子の脱甲化と活性化の動態
Z Paroush1, I Keshet, J Yisraeli
1Department of Cellular Biochemistry, Hebrew University Medical School, Jerusalem, Israel.
Cell
|December 21, 1990
まとめ
遺伝子の脱メチル化は,ネズミのアルファアクチン遺伝子を活性化するために不可欠な2段階のプロセスです. この表遺伝的変異はDNA複製なしに発生し,細胞の微分化中に遺伝子転写を可能にします.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- 遺伝子規制 遺伝子規制
背景:
- ネズミのアルファアクチン遺伝子プロモーターの調節は,筋肉の発達に不可欠です.
- DNAメチル化パターンは,遺伝子発現を制御する上で重要な役割を果たします.
研究 の 目的:
- ラットのアルファ-アクチン遺伝子プロモーターの脱メチル化プロセスを,一時的な変異後に調査する.
- アルファアクチン遺伝子転写の活性化におけるDNA脱メチル化の役割を決定する.
主な方法:
- ネズミのアルファアクチン遺伝子コンストラクタがL8ミオブラストに一時的に変異した.
- トランスフェクション後の時間における遺伝子活性測定.
- 脱メチル化に関与するシス作用の元素を特定するための遺伝子分析.
主要な成果:
- 脱メチル化は2段階で行われ,半メチル化された中間物質が形成されます.
- 遺伝子の活性化には,CpGロシにおける両方のDNA鎖の完全な脱メチル化が必要である.
- 脱メチル化は,DNA複製とは無関係に進行する.
- 脱メチル化を調節するCis作用の要素が特定されました.
結論:
- エピジェネティック改変,特に脱メチル化は,ラットのアルファ-アクチン遺伝子を活性化するために不可欠です.
- 脱メチル化のタイミングは,早期の細胞分化と一致しており,転写因子に遺伝子をアクセシブルにする役割があることを示唆しています.
さらに関連する動画
関連する概念動画
Introduction to Actin
Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle cells, while in non-muscle cells, it is lower and makes up around 1–5 percent of the total cell protein. Actin found in the unicellular amoebae and complex multicellular animals is around 80% similar, demonstrating their conservation over a billion years of evolution. Actin coding genes are conserved within species and across different species.
Actin Polymerization
Actin polymerization occurs through the head-to-tail association of binding sites on monomeric actin or G-actin to form filamentous or F-actin. The polymerization can be divided into three phases ̶ nucleation, elongation, and steady-state phase.
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
Actin and Myosin in Muscle Contraction
Actin and myosin are contractile proteins that form the sarcomere found in skeletal muscle tissues for regulating muscle contraction. Actin, a globular contractile protein, interacts with myosin for muscle contraction. The skeletal tissue appears striped or striated under a microscope due to the repeated arrangement of contractile proteins actin and myosin along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes...
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.
Formation of Muscle Fibers from Myoblasts
De novo myogenesis, or the formation of muscle fibers, begins during the early embryonic stages. The skeletal muscle is formed from somites– blocks of embryonic cell layers. The somites are further divided into dermatomes, myotomes, sclerotomes, and syndetomes. Among these, the myotomes give rise to muscle fibers.
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
Satellite Stem Cells and Muscular Dystrophy
Satellite stem cells or myosatellite cells are quiescent stem cells that Alexander Mauro first identified in 1961. These cells are located between the sarcolemma, the plasma membrane of muscle fibers, and the basal lamina, the connective tissue sheath covering it. These mononucleated cells are activated in response to muscle injury, can transform into myoblasts, and may form or repair muscle fibers. Myosatellite cells can provide additional myonuclei for muscle regeneration or return to a...


