3la3

<StructureSection load='3la3' size='340' side='right' caption='[[3la3]], [[Resolution|resolution]] 2.40&Aring;' scene=''>

<table><tr><td colspan='2'>[[3la3]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Anabaena_7120 Anabaena 7120]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LA3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3LA3 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=2FT:2,2-DIFLUOROPENTANEDIOIC+ACID'>2FT</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3la2|3la2]], [[3la7|3la7]]</td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">alr4392, bifA, ntcA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=103690 Anabaena 7120])</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=3la3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3la3 OCA], [http://pdbe.org/3la3 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3la3 RCSB], [http://www.ebi.ac.uk/pdbsum/3la3 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3la3 ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/NTCA_NOSS1 NTCA_NOSS1]] Required for full expression of proteins subject to ammonium repression. Transcriptional activator of genes subject to nitrogen control. Has affinity for the xisA upstream region. Binds to a 66 bp region containing three repeats of the consensus recognition sequence 5'-ACATT-3'.

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== Publication Abstract from PubMed ==

2-oxogluatarate (2-OG), a metabolite of the highly conserved Krebs cycle, not only plays a critical role in metabolism, but also constitutes a signaling molecule in a variety of organisms ranging from bacteria to plants and animals. In cyanobacteria, the accumulation of 2-OG constitutes the signal of nitrogen starvation and NtcA, a global transcription factor, has been proposed as a putative receptor for 2-OG. Here we present three crystal structures of NtcA from the cyanobacterium Anabaena: the apoform, and two ligand-bound forms in complex with either 2-OG or its analogue 2,2-difluoropentanedioic acid. All structures assemble as homodimers, with each subunit composed of an N-terminal effector-binding domain and a C-terminal DNA-binding domain connected by a long helix (C-helix). The 2-OG binds to the effector-binding domain at a pocket similar to that used by cAMP in catabolite activator protein, but with a different pattern. Comparative structural analysis reveals a putative signal transmission route upon 2-OG binding. A tighter coiled-coil conformation of the two C-helices induced by 2-OG is crucial to maintain the proper distance between the two F-helices for DNA recognition. Whereas catabolite activator protein adopts a transition from off-to-on state upon cAMP binding, our structural analysis explains well why NtcA can bind to DNA even in its apoform, and how 2-OG just enhances the DNA-binding activity of NtcA. These findings provided the structural insights into the function of a global transcription factor regulated by 2-OG, a metabolite standing at a crossroad between carbon and nitrogen metabolisms.

Structural basis for the allosteric control of the global transcription factor NtcA by the nitrogen starvation signal 2-oxoglutarate.,Zhao MX, Jiang YL, He YX, Chen YF, Teng YB, Chen Y, Zhang CC, Zhou CZ Proc Natl Acad Sci U S A. 2010 Jul 13;107(28):12487-92. Epub 2010 Jun 28. PMID:20616047<ref>PMID:20616047</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 3la3" style="background-color:#fffaf0;"></div>

== References ==

<references/>

[[Category: Anabaena 7120]]

[[Category: Chen, Y F]]

[[Category: Chen, Y X]]

[[Category: He, Y X]]

[[Category: Jiang, Y L]]

[[Category: Teng, Y B]]

[[Category: Zhang, C C]]

[[Category: Zhao, M X]]

[[Category: Zhou, C Z]]

[[Category: Transcription regulation]]