myosine1

Myosin I, also known as myosine1, is a member of the myosin superfamily of motor proteins that are primarily involved in cellular movement and cargo transport within eukaryotic cells. These proteins are characterized by their ability to convert chemical energy derived from ATP hydrolysis into mechanical work, facilitating movement along actin filaments.

Myosin I is classified as a monomeric or single-headed myosin, distinguishing it from other myosin classes that are typically dimeric. Its structure generally consists of a motor domain responsible for ATP binding and actin interaction, a neck region with IQ motifs that bind light chains, and a tail domain that mediates interactions with various cellular membranes and cargo molecules. This architecture enables myosin I to perform a variety of functions, including membrane tension regulation, endocytosis, and vesicle trafficking.

Functionally, myosin I is involved in maintaining cell shape, facilitating membrane dynamics, and supporting intracellular transport processes. It plays a critical role in linking the actin cytoskeleton to cellular membranes, thus participating in processes such as phagocytosis, cell motility, and signal transduction.

Myosin I genes are conserved across diverse organisms, from yeast to humans, illustrating their fundamental biological importance. In humans, several isoforms of myosin I have been identified, each exhibiting specific tissue distributions and functions. Dysregulation or mutations in myosin I genes have been associated with various pathological conditions, including neurodegenerative diseases and certain forms of cancer.

Overall, myosin I is a versatile motor protein essential for numerous cellular activities related to actin-based motility and membrane-cytoskeleton interactions.