View source for 9nnz


==Structure of rod opsin in complex with a megabody==
<StructureSection load='9nnz' size='340' side='right'caption='[[9nnz]], [[Resolution|resolution]] 3.94&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9nnz]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9NNZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9NNZ FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.94&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=9nnz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9nnz OCA], [https://pdbe.org/9nnz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9nnz RCSB], [https://www.ebi.ac.uk/pdbsum/9nnz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9nnz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/OPSD_BOVIN OPSD_BOVIN] Photoreceptor required for image-forming vision at low light intensity. Required for photoreceptor cell viability after birth. Light-induced isomerization of 11-cis to all-trans retinal triggers a conformational change leading to G-protein activation and release of all-trans retinal (By similarity).<ref>PMID:16908857</ref> <ref>PMID:17060607</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Rhodopsin, the most intensively studied G protein-coupled receptor (GPCR), is activated by light-induced isomerization of its chromophore 11-cis-retinal. This study employed cryogenic electron microscopy (cryo-EM) to investigate rhodopsin structure using a megabody (Mb7) as a negative allosteric modulator. Three distinct cryo-EM structures were solved: ground-state rhodopsin, photoactivated rhodopsin, and apo-rhodopsin, all in complex with Mb7. Photoactivated rhodopsin and apo-rhodopsin, both in complex with Mb7, maintain a conformation remarkably similar to ground-state rhodopsin rather than adopting a Meta-II-like conformation. Structural elements, including the conserved residues of the NPxxY motif and the ionic lock, remain in positions corresponding to inactive rhodopsin. The megabody forms extensive interactions with rhodopsin's extracellular loop 2, N terminus, and glycans. The findings demonstrate that Mb7 stabilizes photoactivated rhodopsin in a Meta-I-like conformation, preventing progression to the active Meta-II state through specific immobilization of the extracellular domain. This work establishes a foundation for cryo-EM-guided discovery of ligands modulating rhodopsin.

Structural analysis of rhodopsin states in megabody complexes.,Salom D, Suder DS, Huang W, Wu A, Pardon E, Steyaert J, Kiser PD, Taylor DJ, Gonen S, Palczewski K Proc Natl Acad Sci U S A. 2026 Feb 10;123(6):e2532336123. doi: , 10.1073/pnas.2532336123. Epub 2026 Feb 6. PMID:41650224<ref>PMID:41650224</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9nnz" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Bos taurus]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Gonen S]]
[[Category: Suder DS]]