Members of the myosin superfamily of actin-based motors act in a variety of
cellular functions such as muscle contraction, cell and organelle movement,
membrane trafficking, and signal transduction. Although myosin motor domains
(see <PDOC51456>) show a high degree of sequence conservation, the individual
myosin classes are clearly defined by differences in the head structure. The
N-terminal region of myosins from different classes varies greatly in length
and amino acid composition among the individual members. Many myosins have an
SH3-like domain at the N-terminus of the motor domain. This includes myosins
in classes II, V, VI, XI, XXII and XXIV. The myosin N-terminal SH3-like domain
may mediate some aspect of the conformational communication that occurs within
the myosin head during actin and nucleotide binding. Part of this effect may
be mediated through interactions with the neck-associated essential light
chains that are in close proximity to this portion of the head domain and also
transiently interact with actin [1,2,3,4].
The myosin N-terminal SH3-like domain comprises ~50 amino acids and forms a
protruding, six-stranded, antiparallel, β-barrel domain (see <PDB:1OE9>)
with similarities to the SH3 domain (see <PDOC50002>) [1,5].
The profile we developed covers the entire myosin N-terminal SH3-like domain.
October 2017 / First entry.
PROSITE method (with tools and information) covered by this documentation:
Fujita-Becker S. Tsiavaliaris G. Ohkura R. Shimada T. Manstein D.J. Sutoh K.
Functional characterization of the N-terminal region of myosin-2.
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