Chloride Ion Channel - Revision history

Alexander Berchansky at 15:43, 3 October 2021

2021-10-03T15:43:43Z

←Older revision		Revision as of 15:43, 3 October 2021
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-	~~{{STRUCTURE_1k0o \| PDB~~=1k0o ~~\| SCENE~~=User:Laura_Fountain/Sandbox_1/1k0o/1}}	+	<StructureSection load='1k0o' size='300' side='right' scene='User:Laura_Fountain/Sandbox_1/1k0o/1' caption=''>
		+
	== CLIC1: A Chloride Ion Channel ==		== CLIC1: A Chloride Ion Channel ==

-	The CLIC family consists of seven members: CLIC1-5, p64, and parchorin. CLIC1 is the most commonly studied member of the CLIC family because it is expressed to some extent in most tissues and cell types that have been studied and is particularly highly expressed in muscle.<ref name="Tulk">PMID:11940526</ref> Along with being present in the plasma membrane, CLIC1 has been found in various intracellular membranes, such as those of the mitochondria, nucleus (where it is designated NCC27), vesicles, and the endoplasmic reticulum.<ref name="Cromer">PMID:12202911</ref><ref name="Harrop">PMID:11551966</ref>	+	The CLIC family consists of seven members: CLIC1-5, p64, and parchorin. CLIC1 is the most commonly studied member of the CLIC family because it is expressed to some extent in most tissues and cell types that have been studied and is particularly highly expressed in muscle.<ref name="Tulk">PMID:11940526</ref> Along with being present in the plasma membrane, CLIC1 has been found in various intracellular membranes, such as those of the mitochondria, nucleus (where it is designated NCC27), vesicles, and the endoplasmic reticulum.<ref name="Cromer">PMID:12202911</ref><ref name="Harrop">PMID:11551966</ref>

	This wide range of locations in the cell causes a plausible reason to assume that the CLIC chloride channel family participate in an equally wide variety of physiological processes. Some of these include cell division, kidney function, bone resorption, transepithelial transport, and signal transduction. <ref name="Cromer">PMID:12202911</ref>		This wide range of locations in the cell causes a plausible reason to assume that the CLIC chloride channel family participate in an equally wide variety of physiological processes. Some of these include cell division, kidney function, bone resorption, transepithelial transport, and signal transduction. <ref name="Cromer">PMID:12202911</ref>
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	== Structure ==		== Structure ==
-
-	<applet load='1k0o' size='300' frame='true' align='right' caption='Dimer view of CLIC1' />

	The CLIC family is defined by a COOH-terminal core segment of ~230 amino acids that are highly conserved among the family members. CLIC1 only contains a few amino acids upstream of the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/3'>conserved core</scene>.<ref name="Tulk">PMID:11940526</ref>		The CLIC family is defined by a COOH-terminal core segment of ~230 amino acids that are highly conserved among the family members. CLIC1 only contains a few amino acids upstream of the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/3'>conserved core</scene>.<ref name="Tulk">PMID:11940526</ref>
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	At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>		At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>

		+	</StructureSection>
	==3D structure of Chloride ion channel==		==3D structure of Chloride ion channel==

Michal Harel at 06:38, 22 May 2011

2011-05-22T06:38:21Z

←Older revision		Revision as of 06:38, 22 May 2011
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	At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>		At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>
		+
		+	==3D structure of Chloride ion channel==
		+
		+	[[Ion channels]]

	==Additional Resources==		==Additional Resources==

David Canner at 07:43, 2 October 2010

2010-10-02T07:43:21Z

←Older revision		Revision as of 07:43, 2 October 2010
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	At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>		At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>
-
-	== References ==

	==Additional Resources==		==Additional Resources==
-	For additional information, see: [[Membrane Channels & Pumps]	+	For additional information, see: [[Membrane Channels & Pumps]]
	<br />		<br />
		+
		+	== References ==

	<references/>		<references/>
	--[[User:Amy Kerzmann\|Amy Kerzmann]] 00:37, 31 March 2010 (IDT)Content by Laura Fountain		--[[User:Amy Kerzmann\|Amy Kerzmann]] 00:37, 31 March 2010 (IDT)Content by Laura Fountain

David Canner at 07:42, 2 October 2010

2010-10-02T07:42:45Z

←Older revision		Revision as of 07:42, 2 October 2010
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	== References ==		== References ==
		+
		+	==Additional Resources==
		+	For additional information, see: [[Membrane Channels & Pumps]
		+	<br />

	<references/>		<references/>
	--[[User:Amy Kerzmann\|Amy Kerzmann]] 00:37, 31 March 2010 (IDT)Content by Laura Fountain		--[[User:Amy Kerzmann\|Amy Kerzmann]] 00:37, 31 March 2010 (IDT)Content by Laura Fountain

Amy Kerzmann: New page: {{STRUCTURE_1k0o | PDB=1k0o | SCENE=User:Laura_Fountain/Sandbox_1/1k0o/1}} == CLIC1: A Chloride Ion Channel == The CLIC family consists of seven members: CLIC1-5, p64, and parchorin. CL...

2010-03-30T21:37:02Z

New page: {{STRUCTURE_1k0o | PDB=1k0o | SCENE=User:Laura_Fountain/Sandbox_1/1k0o/1}} == CLIC1: A Chloride Ion Channel == The CLIC family consists of seven members: CLIC1-5, p64, and parchorin. CL...

New page

{{STRUCTURE_1k0o | PDB=1k0o | SCENE=User:Laura_Fountain/Sandbox_1/1k0o/1}}
== CLIC1: A Chloride Ion Channel ==

The CLIC family consists of seven members: CLIC1-5, p64, and parchorin. CLIC1 is the most commonly studied member of the CLIC family because it is expressed to some extent in most tissues and cell types that have been studied and is particularly highly expressed in muscle.<ref name="Tulk">PMID:11940526</ref> Along with being present in the plasma membrane, CLIC1 has been found in various intracellular membranes, such as those of the mitochondria, nucleus (where it is designated NCC27), vesicles, and the endoplasmic reticulum.<ref name="Cromer">PMID:12202911</ref><ref name="Harrop">PMID:11551966</ref>

This wide range of locations in the cell causes a plausible reason to assume that the CLIC chloride channel family participate in an equally wide variety of physiological processes. Some of these include cell division, kidney function, bone resorption, transepithelial transport, and signal transduction. <ref name="Cromer">PMID:12202911</ref>

CLIC1 is a member of the highly conserved class of chloride ion channels that exist in both soluble and integral membrane forms. When disrupted cells are washed approximately half of the CLIC1 proteins will remain within the fractioned membrane as would be expected from an integral membrane protein. Atypically, the other half will behave as a soluble cytoplasmic protein and exist within the aqueous extract.<ref name="Tulk">PMID:11940526</ref> Tulk et. al. showed that functionality of the protein isn't greatly effected by the method with which the protein inserts itself into the membrane.

This is part of the evidence which leads Tulk et. al. to postulate that CLIC1 is among the small group of proteins which are assembled as soluble cytoplasmic proteins, which will then insert themselves into the appropriate membrane via their own mechanism.

== Structure ==

<applet load='1k0o' size='300' frame='true' align='right' caption='Dimer view of CLIC1' />

The CLIC family is defined by a COOH-terminal core segment of ~230 amino acids that are highly conserved among the family members. CLIC1 only contains a few amino acids upstream of the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/3'>conserved core</scene>.<ref name="Tulk">PMID:11940526</ref>

It has a homodimeric structure with one pore per subunit, which creates an incredibly unique "double barreled" channel. The <scene name='User:Laura_Fountain/Sandbox_1/1k0o/4'>N-domain</scene> of CLIC1 (~ amino acids 1-90) consists of <scene name='User:Laura_Fountain/Sandbox_1/1k0o/5'>4 beta-sheets</scene> and <scene name='User:Laura_Fountain/Sandbox_1/1k0o/6'>3 alpha-helices</scene>, and the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/7'>C-domain</scene> consists entirely of alpha-helices. The <scene name='User:Laura_Fountain/Sandbox_1/1k0o/9'>long loop between helices</scene> at the foot of CLIC1 (Pro147–Gln164) is a distinctive feature of the CLICs. It is highly negatively charged with seven acidic residues.<ref name="Harrop">PMID:11551966</ref>

Integration of CLIC1 into the membrane is a highly prospect mechanism, but it is likely to require a major structural rearrangement, probably of the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/4'>N-domain</scene><ref name="Harrop">PMID:11551966</ref>, which would insert itself and then allow the <scene name='User:Laura_Fountain/Sandbox_1/1k0o/7'>C-domain</scene> helices to insert and form the pore.

== Selectivity for Chloride ==

Based on the similarity of CLIC1's <scene name='User:Laura_Fountain/Sandbox_1/Channel/1'>antiparallel alpha helical loop</scene> (residues 101-145) to those of other better understood proteins which are able to insert themselves into the membrane, Tulk et. al. propose that this is the single area of the protein which is able to transverse the membrane and also serve as a pore. The <scene name='User:Laura_Fountain/Sandbox_1/Channel/3'>5 positively</scene> and <scene name='User:Laura_Fountain/Sandbox_1/Channel/4'>5 negatively</scene> charged amino acids on each end of the alpha helices could be part of the ion selectivity of this channel.<ref name="Tulk">PMID:11940526</ref>

== Potential Ion Gating ==

At its binding site in the pore, chloride could interact with the ends of four helices that come from both sides of the membrane. A <scene name='User:Laura_Fountain/Sandbox_1/Channel/5'>glutamate residue</scene> that protrudes into the pore is proposed to participate in gating due to its negative charge.<ref name="CLC">PMID:12163078</ref>

== References ==

<references/>
--[[User:Amy Kerzmann|Amy Kerzmann]] 00:37, 31 March 2010 (IDT)Content by Laura Fountain