Summary: Myosin head (motor domain)
Myosin head (motor domain) Provide feedback
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Rayment I, Holden HM, Whittaker M, Yohn CB, Lorenz M, Holmes KC, Milligan RA; , Science 1993;261:58-65.: Structure of the actin-myosin complex and its implications for muscle contraction. PUBMED:8316858 EPMC:8316858
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This tab holds annotation information from the InterPro database.
InterPro entry IPR001609
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 [PUBMED: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 [PUBMED:2806546]. Myosin interacts with actin to convert chemical energy, in the form of ATP, to mechanical energy [PUBMED:3540939]. The 3-D structure of the head portion of myosin has been determined [PUBMED:8316857] and a model for actin-myosin complex has been constructed [PUBMED:8316858].
The globular head is well conserved, some highly-conserved regions possibly relating to functional and structural domains [PUBMED: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 [PUBMED:6576334].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||myosin complex (GO:0016459)|
|Molecular function||ATP binding (GO:0005524)|
|motor activity (GO:0003774)|
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Curation and family details
|Seed source:||Blastp MYSA_HUMAN/1-840|
|Number in seed:||24|
|Number in full:||7667|
|Average length of the domain:||481.40 aa|
|Average identity of full alignment:||32 %|
|Average coverage of the sequence by the domain:||44.72 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||16|
|Download:||download the raw HMM for this family|
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There are 7 interactions for this family. More...
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Myosin_head domain has been found. There are 171 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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