View source for 4jhh


==Crystal Structure of Medicago truncatula Nodulin 13 (MtN13) in complex with kinetin==
<StructureSection load='4jhh' size='340' side='right'caption='[[4jhh]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4jhh]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Medicago_truncatula Medicago truncatula]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4JHH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4JHH 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=H35:N-(FURAN-2-YLMETHYL)-7H-PURIN-6-AMINE'>H35</scene>, <scene name='pdbligand=MLI:MALONATE+ION'>MLI</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=4jhh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4jhh OCA], [https://pdbe.org/4jhh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4jhh RCSB], [https://www.ebi.ac.uk/pdbsum/4jhh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4jhh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NOD13_MEDTR NOD13_MEDTR] May be involved in nodule organogenesis rather in the processes related to nitrogen fixation or interactions with the bacteria. May regulate nodulation by controlling the levels of freely available cytokinins.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Nodulation is an extraordinary symbiotic interaction between leguminous plants and nitrogen-fixing bacteria (rhizobia) that assimilate atmospheric nitrogen (in root nodules) and convert it into compounds suitable for the plant host. A class of plant hormones called cytokinins are involved in the nodulation process. In the model legume Medicago truncatula, nodulin 13 (MtN13), which belongs to the pathogenesis-related proteins of class 10 (PR-10), is expressed in the outer cortex of the nodules. In general, PR-10 proteins are small and monomeric and have a characteristic fold with an internal hydrophobic cavity formed between a seven-stranded antiparallel beta-sheet and a C-terminal alpha-helix. Previously, some PR-10 proteins not related to nodulation were found to bind cytokinins such as trans-zeatin. Here, four crystal structures of the MtN13 protein are reported in complexes with several cytokinins, namely trans-zeatin, N(6)-isopentenyladenine, kinetin and N(6)-benzyladenine. All four phytohormones are bound in the hydrophobic cavity in the same manner and have excellent definition in the electron-density maps. The binding of the cytokinins appears to be strong and specific and is reinforced by several hydrogen bonds. Although the binding stoichiometry is 1:1, the complex is actually dimeric, with a cytokinin molecule bound in each subunit. The ligand-binding site in each cavity is formed with the participation of a loop element from the other subunit, which plugs the only entrance to the cavity. Interestingly, a homodimer of MtN13 is also formed in solution, as confirmed by small-angle X-ray scattering (SAXS).

The landscape of cytokinin binding by a plant nodulin.,Ruszkowski M, Szpotkowski K, Sikorski M, Jaskolski M Acta Crystallogr D Biol Crystallogr. 2013 Dec;69(Pt 12):2365-80. doi:, 10.1107/S0907444913021975. Epub 2013 Nov 19. PMID:24311578<ref>PMID:24311578</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4jhh" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Medicago truncatula]]
[[Category: Jaskolski M]]
[[Category: Ruszkowski M]]
[[Category: Sikorski M]]