4r22

<StructureSection load='4r22' size='340' side='right' caption='[[4r22]], [[Resolution|resolution]] 2.60&Aring;' scene=''>

<table><tr><td colspan='2'>[[4r22]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4R22 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4R22 FirstGlance]. <br>

</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4r24|4r24]], [[4r25|4r25]]</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=4r22 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4r22 OCA], [http://pdbe.org/4r22 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4r22 RCSB], [http://www.ebi.ac.uk/pdbsum/4r22 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4r22 ProSAT]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

All cells must sense and adapt to changing nutrient availability. However, detailed molecular mechanisms coordinating such regulatory pathways remain poorly understood. In Bacillus subtilis, nitrogen homeostasis is controlled by a unique circuitry composed of the regulator TnrA, which is deactivated by feedback-inhibited glutamine synthetase (GS) during nitrogen excess and stabilized by GlnK upon nitrogen depletion, and the repressor GlnR. Here we describe a complete molecular dissection of this network. TnrA and GlnR, the global nitrogen homeostatic transcription regulators, are revealed as founders of a new structural family of dimeric DNA-binding proteins with C-terminal, flexible, effector-binding sensors that modulate their dimerization. Remarkably, the TnrA sensor domains insert into GS intersubunit catalytic pores, destabilizing the TnrA dimer and causing an unprecedented GS dodecamer-to-tetradecamer conversion, which concomitantly deactivates GS. In contrast, each subunit of the GlnK trimer "templates" active TnrA dimers. Unlike TnrA, GlnR sensors mediate an autoinhibitory dimer-destabilizing interaction alleviated by GS, which acts as a GlnR chaperone. Thus, these studies unveil heretofore unseen mechanisms by which inducible sensor domains drive metabolic reprograming in the model Gram-positive bacterium B. subtilis.

 

Structures of regulatory machinery reveal novel molecular mechanisms controlling B. subtilis nitrogen homeostasis.,Schumacher MA, Chinnam NB, Cuthbert B, Tonthat NK, Whitfill T Genes Dev. 2015 Feb 15;29(4):451-64. doi: 10.1101/gad.254714.114. PMID:25691471<ref>PMID:25691471</ref>

 

[[Category: Schumacher, M A]]

[[Category: G]]

[[Category: New family of transcription regulator]]

[[Category: Transcription]]

[[Category: Transcription-dna complex]]