This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2dfs
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="2dfs" size="450" color="white" frame="true" align="right" spinBox="true" caption="2dfs" /> '''3-D structure of Myosin-V inhibited state'''...)
Next diff →
Revision as of 07:28, 21 November 2007
|
3-D structure of Myosin-V inhibited state
Overview
Unconventional myosin V (myoV) is an actin-based molecular motor that has, a key function in organelle and mRNA transport, as well as in membrane, trafficking. MyoV was the first member of the myosin superfamily shown to, be processive, meaning that a single motor protein can 'walk', hand-over-hand along an actin filament for many steps before detaching., Full-length myoV has a low actin-activated MgATPase activity at low, [Ca2+], whereas expressed constructs lacking the cargo-binding domain have, a high activity regardless of [Ca2+] (refs 5-7). Hydrodynamic data and, electron micrographs indicate that the active state is extended, whereas, the inactive state is compact. Here we show the first three-dimensional, structure of the myoV inactive state. Each myoV molecule consists of two, heads that contain an amino-terminal motor domain followed by a lever arm, that binds six calmodulins. The heads are followed by a coiled-coil, dimerization domain (S2) and a carboxy-terminal globular cargo-binding, domain. In the inactive structure, bending of myoV at the head-S2 junction, places the cargo-binding domain near the motor domain's ATP-binding, pocket, indicating that ATPase inhibition might occur through decreased, rates of nucleotide exchange. The actin-binding interfaces are, unobstructed, and the lever arm is oriented in a position typical of, strong actin-binding states. This structure indicates that motor recycling, after cargo delivery might occur through transport on actively, treadmilling actin filaments rather than by diffusion.
About this Structure
2DFS is a Protein complex structure of sequences from Gallus gallus and Mus musculus. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of the myosin V inhibited state by cryoelectron tomography., Liu J, Taylor DW, Krementsova EB, Trybus KM, Taylor KA, Nature. 2006 Jul 13;442(7099):208-11. Epub 2006 Apr 16. PMID:16625208
Page seeded by OCA on Wed Nov 21 09:35:27 2007
