View source for 7xbr


==Crystal structure of phosphorylated AtMKK5==
<StructureSection load='7xbr' size='340' side='right'caption='[[7xbr]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7xbr]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7XBR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7XBR FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SEP:PHOSPHOSERINE'>SEP</scene>, <scene name='pdbligand=TPO:PHOSPHOTHREONINE'>TPO</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7xbr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7xbr OCA], [https://pdbe.org/7xbr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7xbr RCSB], [https://www.ebi.ac.uk/pdbsum/7xbr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7xbr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/M2K5_ARATH M2K5_ARATH] Mitogen-activated protein kinase kinase (MAPKK) which regulates abscisic acid (ABA) responses in a MAPKKK20-MKK5-MPK6 cascade involved in root growth (e.g. root cell division and elongation) and stomatal response, probably via MAPK6 activation by protein phosphorylation (PubMed:27913741). Involved in the second phase of hydrogen peroxide generation during hypersensitive response-like cell death. Involved in the innate immune MAP kinase signaling cascade (MEKK1, MKK4/MKK5 and MPK3/MPK6) downstream of bacterial flagellin receptor FLS2. Activates by phosphorylation the downstream MPK3 and MPK6. YDA-MKK4/MKK5-MPK3/MPK6 module regulates stomatal cell fate before the guard mother cell (GMC) is specified. This MAPK cascade also functions downstream of the ER receptor in regulating coordinated local cell proliferation, which shapes the morphology of plant organs. MKK4 and MKK5 participate in the regulation of floral organ abscission. Target of the Pseudomonas syringae type III effector HopF2, that inhibits the activation of the downstream MPK6 and PAMP-triggered immunity. Plays a critical role in high light stress tolerance by the mediation of the Cu/Zn SODs CSD1 and CSD2 gene expression. Phosphorylates BZR1 in vitro.<ref>PMID:11687590</ref> <ref>PMID:11875555</ref> <ref>PMID:17259259</ref> <ref>PMID:18268539</ref> <ref>PMID:18809915</ref> <ref>PMID:20571112</ref> <ref>PMID:23263767</ref> <ref>PMID:23341468</ref> <ref>PMID:23677921</ref> <ref>PMID:24019147</ref> <ref>PMID:27913741</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The mitogen-activated protein kinase (MAPK) signaling pathways are highly conserved in eukaryotes, regulating various cellular processes. The MAPK kinases (MKKs) are dual specificity kinases, serving as convergence and divergence points of the tripartite MAPK cascades. Here, we investigate the biochemical characteristics and three-dimensional structure of MKK5 in Arabidopsis (AtMKK5). The recombinant full-length AtMKK5 is phosphorylated and can activate its physiological substrate AtMPK6. There is a conserved kinase interacting motif (KIM) at the N-terminus of AtMKK5, indispensable for specific recognition of AtMPK6. The kinase domain of AtMKK5 adopts active conformation, of which the extended activation segment is stabilized by the phosphorylated Ser221 and Thr215 residues. In line with sequence divergence from other MKKs, the alphaD and alphaK helices are missing in AtMKK5, suggesting that the AtMKK5 may adopt distinct modes of upstream kinase/substrate binding. Our data shed lights on the molecular mechanisms of MKK activation and substrate recognition, which may help design specific inhibitors targeting human and plant MKKs.

Crystal structure of the phosphorylated Arabidopsis MKK5 reveals activation mechanism of MAPK kinases.,Pei CJ, He QX, Luo Z, Yao H, Wang ZX, Wu JW Acta Biochim Biophys Sin (Shanghai). 2022 Aug 25;54(8):1159-1170. doi: , 10.3724/abbs.2022089. PMID:35866601<ref>PMID:35866601</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7xbr" style="background-color:#fffaf0;"></div>

==See Also==
*[[Mitogen-activated protein kinase kinase 3D structures|Mitogen-activated protein kinase kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Arabidopsis thaliana]]
[[Category: Large Structures]]
[[Category: Luo ZP]]
[[Category: Pei CJ]]
[[Category: Wang ZX]]
[[Category: Wu JW]]