1jo6: Difference between revisions

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[[Image:1jo6.gif|left|200px]]<br />

[[Image:1jo6.gif|left|200px]]<br /><applet load="1jo6" size="350" color="white" frame="true" align="right" spinBox="true"

<applet load="1jo6" size="~~450~~" color="white" frame="true" align="right" spinBox="true"

caption="1jo6" />

'''Solution structure of the cytoplasmic N-terminus of the BK beta-subunit KCNMB2'''<br />

==Overview==

The auxiliary beta-subunit KCNMB2 (beta(2)) endows the non-inactivating, large conductance Ca(2+)- and voltage-dependent potassium (BK) channel, with fast inactivation. This process is mediated by the N terminus of, KCNMB2 and closely resembles the "ball-and-chain"-type inactivation, observed in voltage-gated potassium channels. Here we investigated the, solution structure and function of the KCNMB2 N terminus (amino acids, 1-45, BKbeta(2)N) using NMR spectroscopy and patch clamp recordings., BKbeta(2)N completely inactivated BK channels when applied to the, cytoplasmic side; its interaction with the BK alpha-subunit is, characterized by a particularly slow dissociation rate and an affinity in, the upper nanomolar range. The BKbeta(2)N structure comprises two domains, connected by a flexible linker: the pore-blocking "ball domain" (formed by, residues 1-17) and the "chain domain" (between residues 20-45) linking it, to the membrane segment of KCNMB2. The ball domain is made up of a, flexible N terminus anchored at a well ordered loop-helix motif. The chain, domain consists of a 4-turn helix with an unfolded linker at its C, terminus. These structural properties explain the functional, characteristics of BKbeta(2)N-mediated inactivation.

The auxiliary beta-subunit KCNMB2 (beta(2)) endows the non-inactivating large conductance Ca(2+)- and voltage-dependent potassium (BK) channel with fast inactivation. This process is mediated by the N terminus of KCNMB2 and closely resembles the "ball-and-chain"-type inactivation observed in voltage-gated potassium channels. Here we investigated the solution structure and function of the KCNMB2 N terminus (amino acids 1-45, BKbeta(2)N) using NMR spectroscopy and patch clamp recordings. BKbeta(2)N completely inactivated BK channels when applied to the cytoplasmic side; its interaction with the BK alpha-subunit is characterized by a particularly slow dissociation rate and an affinity in the upper nanomolar range. The BKbeta(2)N structure comprises two domains connected by a flexible linker: the pore-blocking "ball domain" (formed by residues 1-17) and the "chain domain" (between residues 20-45) linking it to the membrane segment of KCNMB2. The ball domain is made up of a flexible N terminus anchored at a well ordered loop-helix motif. The chain domain consists of a 4-turn helix with an unfolded linker at its C terminus. These structural properties explain the functional characteristics of BKbeta(2)N-mediated inactivation.

==About this Structure==

1JO6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://~~ispc~~.weizmann.ac.il/oca-bin/ocashort?id=1JO6 OCA].

1JO6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JO6 OCA].

==Reference==

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[[Category: ion channel]]

''Page seeded by [http://~~ispc~~.weizmann.ac.il/oca OCA ] on ~~Mon Nov 12 17~~:42:~~57 2007~~''

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:24:47 2008''

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@@ Line 1: / Line 1: @@
-[[Image:1jo6.gif|left|200px]]<br />
+[[Image:1jo6.gif|left|200px]]<br /><applet load="1jo6" size="350" color="white" frame="true" align="right" spinBox="true"
-<applet load="1jo6" size="450" color="white" frame="true" align="right" spinBox="true"
 caption="1jo6" />
 '''Solution structure of the cytoplasmic N-terminus of the BK beta-subunit KCNMB2'''<br />
 ==Overview==
-The auxiliary beta-subunit KCNMB2 (beta(2)) endows the non-inactivating, large conductance Ca(2+)- and voltage-dependent potassium (BK) channel, with fast inactivation. This process is mediated by the N terminus of, KCNMB2 and closely resembles the "ball-and-chain"-type inactivation, observed in voltage-gated potassium channels. Here we investigated the, solution structure and function of the KCNMB2 N terminus (amino acids, 1-45, BKbeta(2)N) using NMR spectroscopy and patch clamp recordings., BKbeta(2)N completely inactivated BK channels when applied to the, cytoplasmic side; its interaction with the BK alpha-subunit is, characterized by a particularly slow dissociation rate and an affinity in, the upper nanomolar range. The BKbeta(2)N structure comprises two domains, connected by a flexible linker: the pore-blocking "ball domain" (formed by, residues 1-17) and the "chain domain" (between residues 20-45) linking it, to the membrane segment of KCNMB2. The ball domain is made up of a, flexible N terminus anchored at a well ordered loop-helix motif. The chain, domain consists of a 4-turn helix with an unfolded linker at its C, terminus. These structural properties explain the functional, characteristics of BKbeta(2)N-mediated inactivation.
+The auxiliary beta-subunit KCNMB2 (beta(2)) endows the non-inactivating large conductance Ca(2+)- and voltage-dependent potassium (BK) channel with fast inactivation. This process is mediated by the N terminus of KCNMB2 and closely resembles the "ball-and-chain"-type inactivation observed in voltage-gated potassium channels. Here we investigated the solution structure and function of the KCNMB2 N terminus (amino acids 1-45, BKbeta(2)N) using NMR spectroscopy and patch clamp recordings. BKbeta(2)N completely inactivated BK channels when applied to the cytoplasmic side; its interaction with the BK alpha-subunit is characterized by a particularly slow dissociation rate and an affinity in the upper nanomolar range. The BKbeta(2)N structure comprises two domains connected by a flexible linker: the pore-blocking "ball domain" (formed by residues 1-17) and the "chain domain" (between residues 20-45) linking it to the membrane segment of KCNMB2. The ball domain is made up of a flexible N terminus anchored at a well ordered loop-helix motif. The chain domain consists of a 4-turn helix with an unfolded linker at its C terminus. These structural properties explain the functional characteristics of BKbeta(2)N-mediated inactivation.
 ==About this Structure==
-JO6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1JO6 OCA].
+JO6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JO6 OCA].
 ==Reference==
@@ Line 21: / Line 20: @@
 [[Category: ion channel]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 12 17:42:57 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:24:47 2008''