muscle cell development

Definition

Target type: biologicalprocess

The process whose specific outcome is the progression of a muscle cell over time, from its formation to the mature structure. Muscle cell development does not include the steps involved in committing an unspecified cell to the muscle cell fate. [CL:0000187, GOC:devbiol]

Muscle cell development, also known as myogenesis, is a complex and highly regulated process that involves the differentiation of undifferentiated precursor cells, known as myoblasts, into mature muscle fibers. This process begins during embryonic development and continues throughout life, allowing for muscle growth, repair, and regeneration.

The process of myogenesis can be broadly divided into several key stages:

1. **Commitment and Determination:** Myoblasts originate from mesenchymal stem cells, which are multipotent cells capable of differentiating into various cell types, including muscle cells. Specific transcription factors, such as Myf5 and MyoD, are activated in these cells, committing them to the myogenic lineage. These factors induce the expression of genes involved in muscle cell development and suppress the expression of genes involved in other cell lineages.

2. **Proliferation and Growth:** Once committed, myoblasts undergo rapid proliferation, increasing their numbers through cell division. This stage is crucial for generating a sufficient pool of myoblasts needed for muscle formation. Growth factors, such as insulin-like growth factor 1 (IGF-1) and fibroblast growth factor (FGF), play a significant role in promoting myoblast proliferation.

3. **Differentiation and Fusion:** As myoblasts reach a critical density, they exit the cell cycle and initiate differentiation. This involves a dramatic change in gene expression, where genes involved in muscle-specific functions, such as contractility and metabolism, are upregulated. Myoblasts then fuse together to form multinucleated myotubes, the precursors of mature muscle fibers.

4. **Maturation and Myofiber Formation:** Myotubes undergo further maturation and specialization, developing a complex internal structure with organized sarcomeres (the contractile units of muscle). They also acquire a specialized membrane, known as the sarcolemma, and begin to express proteins necessary for muscle function, such as myosin, actin, and troponin.

5. **Muscle Fiber Growth and Regeneration:** After the initial formation of myofibers, muscle growth can occur through hypertrophy, an increase in the size of existing muscle fibers. This involves the synthesis of new contractile proteins and the formation of additional sarcomeres. Muscle regeneration, the repair of damaged muscle tissue, is another important aspect of myogenesis. This process involves the activation of satellite cells, a population of quiescent stem cells located beneath the sarcolemma. Satellite cells can proliferate and differentiate into myoblasts, contributing to muscle repair.

Myogenesis is a highly regulated process that is influenced by a variety of factors, including genetic factors, environmental cues, and physical activity. Understanding this process is essential for addressing muscle-related diseases and developing therapies for muscle regeneration.'
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Proteins (6)

Compounds (84)