User:Amy Kerzmann/Sandbox 2
From Proteopedia
(→Voltage-gated Potassium Channel) |
(→Voltage-gated Potassium Channel) |
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'''Channel Structure:''' | '''Channel Structure:''' | ||
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| - | The potassium channel is a homotetramer | + | The potassium channel is a homotetramer, meaning that it is comprised of four identical <scene name='User:Amy_Kerzmann/Sandbox_2/Chain_a/2'>monomers</scene>. |
| - | <applet load=' | + | |
| + | The central core of this protein is comprised of eight helices, two from each monomeric subunit. Since each <scene name='User:Amy_Kerzmann/Sandbox_2/Chain_a/1'>monomer</scene> has the same orientation in the membrane, the protein has a four-fold rotational symmetry when viewed from the membrane surface. As a result, each of the channel-lining residues appears as a ring of four identical sidechains. This principle is represented by the conserved <scene name='User:Amy_Kerzmann/Sandbox_2/Tyrosine_symmetry/1'>tyrosine</scene> residues that function as selectivity filters within the cavity. Additional <scene name='User:Amy_Kerzmann/Sandbox_2/Aspartate_symmetry/1'>aspartate</scene> and <scene name='User:Amy_Kerzmann/Sandbox_2/Threonine_symmetry/2'>threonine</scene> residues line the channel. Looking at a <scene name='User:Amy_Kerzmann/Sandbox_2/Channel-lining_residues/1'>composite</scene> of these residues, one can see that some hydrophobic patches remain within the cavity. | ||
| + | |||
| + | <applet load='User:Amy_Kerzmann/Sandbox_2/Potassium_ions/3' size='300' frame='true' align='right' caption='Insert caption here' /> | ||
Revision as of 21:04, 24 September 2009
Voltage-gated Potassium Channel
Template:STRUCTURE 3cs9 Backgound
This crystal structure illuminated the principles of ion selectivity when it was solved in 1998.[1] To further demonstrate the importance of this structure, the 2003 Nobel Prize in Chemistry was awarded to the principal investigator, Roderick MacKinnon.
Channel Structure:
The potassium channel is a homotetramer, meaning that it is comprised of four identical .
The central core of this protein is comprised of eight helices, two from each monomeric subunit. Since each has the same orientation in the membrane, the protein has a four-fold rotational symmetry when viewed from the membrane surface. As a result, each of the channel-lining residues appears as a ring of four identical sidechains. This principle is represented by the conserved residues that function as selectivity filters within the cavity. Additional and residues line the channel. Looking at a of these residues, one can see that some hydrophobic patches remain within the cavity.
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Channel Function:
Here's how it works.
References
