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2dfs
From Proteopedia
(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'''...) |
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| - | [[Image:2dfs.gif|left|200px]]<br /><applet load="2dfs" size=" | + | [[Image:2dfs.gif|left|200px]]<br /><applet load="2dfs" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2dfs" /> | caption="2dfs" /> | ||
'''3-D structure of Myosin-V inhibited state'''<br /> | '''3-D structure of Myosin-V inhibited state'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Unconventional myosin V (myoV) is an actin-based molecular motor that has | + | 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== | ==About this Structure== | ||
| - | 2DFS is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] and [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http:// | + | 2DFS is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] and [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2DFS OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Krementsova, E | + | [[Category: Krementsova, E B.]] |
[[Category: Liu, J.]] | [[Category: Liu, J.]] | ||
| - | [[Category: Taylor, D | + | [[Category: Taylor, D W.]] |
| - | [[Category: Taylor, K | + | [[Category: Taylor, K A.]] |
| - | [[Category: Trybus, K | + | [[Category: Trybus, K M.]] |
[[Category: calmodulin]] | [[Category: calmodulin]] | ||
[[Category: cryoelectron tomography]] | [[Category: cryoelectron tomography]] | ||
| Line 24: | Line 24: | ||
[[Category: myosin-v]] | [[Category: myosin-v]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:58:29 2008'' |
Revision as of 14:58, 21 February 2008
|
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
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