1lnq: Difference between revisions

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

Ion channels exhibit two essential biophysical properties; that is, selective ion conduction, and the ability to gate-open in response to an appropriate stimulus. Two general categories of ion channel gating are defined by the initiating stimulus: ligand binding (neurotransmitter- or second-messenger-gated channels) or membrane voltage (voltage-gated channels). Here we present the structural basis of ligand gating in a K(+) channel that opens in response to intracellular Ca(2+). We have cloned, expressed, analysed electrical properties, and determined the crystal structure of a K(+) channel (MthK) from Methanobacterium thermoautotrophicum in the Ca(2+)-bound, opened state. Eight RCK domains (regulators of K(+) conductance) form a gating ring at the intracellular membrane surface. The gating ring uses the free energy of Ca(2+) binding in a simple manner to perform mechanical work to open the pore.

1LNQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanothermobacter_thermautotrophicus Methanothermobacter thermautotrophicus] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. The following page contains interesting information on the relation of 1LNQ with [[http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb38_1.html Potassium Channels]]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LNQ OCA].  

[[Category: Chait, B T.]]

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