Myosin head, motor domain (IPR001609)

Short name: Myosin_head_motor_dom

Overlapping homologous superfamilies

Domain relationships


Muscle contraction is caused by sliding between the thick and thin filaments of the myofibril. Myosin is a major component of thick filaments and exists as a hexamer of 2 heavy chains [PMID: 1939027], 2 alkali light chains, and 2 regulatory light chains. The heavy chain can be subdivided into the N-terminal globular head and the C-terminal coiled-coil rod-like tail, although some forms have a globular region in their C-terminal. There are many cell-specific isoforms of myosin heavy chains, coded for by a multi-gene family [PMID: 2806546]. Myosin interacts with actin to convert chemical energy, in the form of ATP, to mechanical energy [PMID: 3540939]. The 3-D structure of the head portion of myosin has been determined [PMID: 8316857] and a model for actin-myosin complex has been constructed [PMID: 8316858].

The globular head is well conserved, some highly-conserved regions possibly relating to functional and structural domains [PMID: 6576334]. The rod-like tail starts with an invariant proline residue, and contains many repeats of a 28 residue region, interrupted at 4 regularly-spaced points known as skip residues. Although the sequence of the tail is not well conserved, the chemical character is, hydrophobic, charged and skip residues occuring in a highly ordered and repeated fashion [PMID: 6576334].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005524 ATP binding
GO:0003774 motor activity

Cellular Component

GO:0016459 myosin complex

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles