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1jba
From Proteopedia
(New page: 200px<br /><applet load="1jba" size="450" color="white" frame="true" align="right" spinBox="true" caption="1jba" /> '''UNMYRISTOYLATED GCAP-2 WITH THREE CALCIUM IO...) |
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| - | [[Image:1jba.jpg|left|200px]]<br /><applet load="1jba" size=" | + | [[Image:1jba.jpg|left|200px]]<br /><applet load="1jba" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1jba" /> | caption="1jba" /> | ||
'''UNMYRISTOYLATED GCAP-2 WITH THREE CALCIUM IONS BOUND'''<br /> | '''UNMYRISTOYLATED GCAP-2 WITH THREE CALCIUM IONS BOUND'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Guanylyl cyclase activating protein-2 (GCAP-2) is a Ca2+-sensitive | + | Guanylyl cyclase activating protein-2 (GCAP-2) is a Ca2+-sensitive regulator of phototransduction in retinal photoreceptor cells. GCAP-2 activates retinal guanylyl cyclases at low Ca2+ concentration (<100 nM) and inhibits them at high Ca2+ (>500 nM). The light-induced lowering of the Ca2+ level from approximately 500 nM in the dark to approximately 50 nM following illumination is known to play a key role in visual recovery and adaptation. We report here the three-dimensional structure of unmyristoylated GCAP-2 with three bound Ca2+ ions as determined by nuclear magnetic resonance spectroscopy of recombinant, isotopically labeled protein. GCAP-2 contains four EF-hand motifs arranged in a compact tandem array like that seen previously in recoverin. The root mean square deviation of the main chain atoms in the EF-hand regions is 2.2 A in comparing the Ca2+-bound structures of GCAP-2 and recoverin. EF-1, as in recoverin, does not bind calcium because it contains a disabling Cys-Pro sequence. GCAP-2 differs from recoverin in that the calcium ion binds to EF-4 in addition to EF-2 and EF-3. A prominent exposed patch of hydrophobic residues formed by EF-1 and EF-2 (Leu24, Trp27, Phe31, Phe45, Phe48, Phe49, Tyr81, Val82, Leu85, and Leu89) may serve as a target-binding site for the transmission of calcium signals to guanylyl cyclase. |
==About this Structure== | ==About this Structure== | ||
| - | 1JBA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Guanylate_cyclase Guanylate cyclase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.6.1.2 4.6.1.2] Full crystallographic information is available from [http:// | + | 1JBA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Guanylate_cyclase Guanylate cyclase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.6.1.2 4.6.1.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JBA OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Guanylate cyclase]] | [[Category: Guanylate cyclase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Ames, J | + | [[Category: Ames, J B.]] |
| - | [[Category: Dizhoor, A | + | [[Category: Dizhoor, A M.]] |
[[Category: Ikura, M.]] | [[Category: Ikura, M.]] | ||
[[Category: Palczewski, K.]] | [[Category: Palczewski, K.]] | ||
| Line 24: | Line 24: | ||
[[Category: guanylyl cyclase regulation]] | [[Category: guanylyl cyclase regulation]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:20:48 2008'' |
Revision as of 11:20, 21 February 2008
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UNMYRISTOYLATED GCAP-2 WITH THREE CALCIUM IONS BOUND
Overview
Guanylyl cyclase activating protein-2 (GCAP-2) is a Ca2+-sensitive regulator of phototransduction in retinal photoreceptor cells. GCAP-2 activates retinal guanylyl cyclases at low Ca2+ concentration (<100 nM) and inhibits them at high Ca2+ (>500 nM). The light-induced lowering of the Ca2+ level from approximately 500 nM in the dark to approximately 50 nM following illumination is known to play a key role in visual recovery and adaptation. We report here the three-dimensional structure of unmyristoylated GCAP-2 with three bound Ca2+ ions as determined by nuclear magnetic resonance spectroscopy of recombinant, isotopically labeled protein. GCAP-2 contains four EF-hand motifs arranged in a compact tandem array like that seen previously in recoverin. The root mean square deviation of the main chain atoms in the EF-hand regions is 2.2 A in comparing the Ca2+-bound structures of GCAP-2 and recoverin. EF-1, as in recoverin, does not bind calcium because it contains a disabling Cys-Pro sequence. GCAP-2 differs from recoverin in that the calcium ion binds to EF-4 in addition to EF-2 and EF-3. A prominent exposed patch of hydrophobic residues formed by EF-1 and EF-2 (Leu24, Trp27, Phe31, Phe45, Phe48, Phe49, Tyr81, Val82, Leu85, and Leu89) may serve as a target-binding site for the transmission of calcium signals to guanylyl cyclase.
About this Structure
1JBA is a Single protein structure of sequence from Bos taurus with as ligand. Active as Guanylate cyclase, with EC number 4.6.1.2 Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of guanylyl cyclase activating protein-2, a calcium-sensitive modulator of photoreceptor guanylyl cyclases., Ames JB, Dizhoor AM, Ikura M, Palczewski K, Stryer L, J Biol Chem. 1999 Jul 2;274(27):19329-37. PMID:10383444
Page seeded by OCA on Thu Feb 21 13:20:48 2008
