1t4y

<StructureSection load='1t4y' size='340' side='right' caption='[[1t4y]], [[NMR_Ensembles_of_Models | 1 NMR models]]' scene=''>

<table><tr><td colspan='2'>[[1t4y]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Anacystis_nidulans_r2 Anacystis nidulans r2]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T4Y OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1T4Y FirstGlance]. <br>

</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1t4z|1t4z]]</td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">SASA, SARS ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1140 Anacystis nidulans R2])</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1t4y FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1t4y OCA], [http://pdbe.org/1t4y PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1t4y RCSB], [http://www.ebi.ac.uk/pdbsum/1t4y PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1t4y ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/SASA_SYNE7 SASA_SYNE7]] May be involved in signal transduction. Participates in the KaiABC clock protein complex, which constitutes the main circadian regulator in cyanobacteria, via its interaction with KaiC. Required for robustness of the circadian rhythm of gene expression and is involved in clock outputs.<ref>PMID:10786837</ref>

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== Publication Abstract from PubMed ==

Circadian oscillators are endogenous biological systems that generate the approximately 24 hour temporal pattern of biological processes and confer a reproductive fitness advantage to their hosts. The cyanobacterial clock is the simplest known and the only clock system for which structural information for core component proteins, in this case KaiA, KaiB and KaiC, is available. SasA, a clock-associated histidine kinase, is necessary for robustness of the circadian rhythm of gene expression and implicated in clock output. The N-terminal domain of SasA (N-SasA) interacts directly with KaiC and likely functions as the sensory domain controlling the SasA histidine kinase activity. N-SasA and KaiB share significant sequence similarity and, thus, it has been proposed that they would be structurally similar and may even compete for KaiC binding. Here, we report the NMR structure of N-SasA and show it to be different from that of KaiB. The structural comparisons provide no clear details to suggest competition of SasA and KaiB for KaiC binding. N-SasA adopts a canonical thioredoxin fold but lacks the catalytic cysteine residues. A patch of conserved, solvent-exposed residues is found near the canonical thioredoxin active site. We suggest that this surface is used by N-SasA for protein-protein interactions. Our analysis suggests that the structural differences between N-SasA and KaiB are the result of only a few critical amino acid substitutions.

Structure of the N-terminal domain of the circadian clock-associated histidine kinase SasA.,Vakonakis I, Klewer DA, Williams SB, Golden SS, LiWang AC J Mol Biol. 2004 Sep 3;342(1):9-17. PMID:15313603<ref>PMID:15313603</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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<div class="pdbe-citations 1t4y" style="background-color:#fffaf0;"></div>

[[Category: Anacystis nidulans r2]]

[[Category: Klewer, D A]]

[[Category: LiWang, A C]]

[[Category: Vakonakis, I]]

[[Category: Alpha/beta protein]]

[[Category: Transferase]]