User:Amy Kerzmann/Sandbox 2

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
(Voltage-gated Potassium Channel)
(Voltage-gated Potassium Channel)
Line 11: Line 11:
Channel Structure:
Channel Structure:
----
----
-
The potassium channel of influenza A is a homotetramer. The central core of this protein is comprised of four transmembrane helices, one from each monomeric subunit. Since all monomers have 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.
+
The potassium channel of influenza A is a homotetramer. The central core of this protein is comprised of eight helices, two from each monomeric subunit. Since all monomers have 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.

Revision as of 17:08, 23 September 2009

Voltage-gated Potassium Channel

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.


First Crystal Structure of a Potassium Channel. (PDB 1bl8)

Drag the structure with the mouse to rotate


Channel Structure:


The potassium channel of influenza A is a homotetramer. The central core of this protein is comprised of eight helices, two from each monomeric subunit. Since all monomers have 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.



Channel Function:


Here's how it works.


References


  1. Doyle DA, Morais Cabral J, Pfuetzner RA, Kuo A, Gulbis JM, Cohen SL, Chait BT, MacKinnon R. The structure of the potassium channel: molecular basis of K+ conduction and selectivity. Science. 1998 Apr 3;280(5360):69-77. PMID:9525859

Proteopedia Page Contributors and Editors (what is this?)

Amy Kerzmann, Jaime Prilusky

Personal tools