View source for 8vw5


==Crystal structure of Cbl-b TKB bound to compound 2==
<StructureSection load='8vw5' size='340' side='right'caption='[[8vw5]], [[Resolution|resolution]] 1.76&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8vw5]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8VW5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8VW5 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]] 1.76&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=A1AD4:[5-(2-{(2R,5S)-2-[2-(carboxymethoxy)-3-methoxy-5-nitrophenyl]-3,5-dimethyl-4-oxoimidazolidin-1-yl}-2-oxoethyl)-3,6-dimethoxy-9,9-dimethyl-9H-xanthen-4-yl]acetic+acid'>A1AD4</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=8vw5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8vw5 OCA], [https://pdbe.org/8vw5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8vw5 RCSB], [https://www.ebi.ac.uk/pdbsum/8vw5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8vw5 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CBLB_HUMAN CBLB_HUMAN] E3 ubiquitin-protein ligase which accepts ubiquitin from specific E2 ubiquitin-conjugating enzymes, and transfers it to substrates, generally promoting their degradation by the proteasome. Negatively regulates TCR (T-cell receptor), BCR (B-cell receptor) and FCER1 (high affinity immunoglobulin epsilon receptor) signal transduction pathways. In naive T-cells, inhibits VAV1 activation upon TCR engagement and imposes a requirement for CD28 costimulation for proliferation and IL-2 production. Also acts by promoting PIK3R1/p85 ubiquitination, which impairs its recruitment to the TCR and subsequent activation. In activated T-cells, inhibits PLCG1 activation and calcium mobilization upon restimulation and promotes anergy. In B-cells, acts by ubiquitinating SYK and promoting its proteasomal degradation. May also be involved in EGFR ubiquitination and internalization.<ref>PMID:10022120</ref> <ref>PMID:10086340</ref> <ref>PMID:11087752</ref> <ref>PMID:11526404</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
We were attracted to the therapeutic potential of inhibiting Casitas B-lineage lymphoma proto-oncogene-b (Cbl-b), a RING E3 ligase that plays a critical role in regulating the activation of T cells. However, given that only protein-protein interactions were involved, it was unclear whether inhibition by a small molecule would be a viable approach. After screening an approximately 6 billion member DNA-encoded library (DEL) using activated Cbl-b, we identified compound 1 as a hit for which the cis-isomer (2) was confirmed by biochemical and surface plasmon resonance (SPR) assays. Our hit optimization effort was greatly accelerated when we obtained a cocrystal structure of 2 with Cbl-b, which demonstrated induced binding at the substrate binding site, namely, the Src homology-2 (SH2) domain. This was quite noteworthy given that there are few reports of small molecule inhibitors that bind to SH2 domains and block protein-protein interactions. Structure- and property-guided optimization led to compound 27, which demonstrated measurable cell activity, albeit only at high concentrations.

Optimization of a Novel DEL Hit That Binds in the Cbl-b SH2 Domain and Blocks Substrate Binding.,Liang J, Lambrecht MJ, Arenzana TL, Aubert-Nicol S, Bao L, Broccatelli F, Cai J, Eidenschenk C, Everett C, Garner T, Gruber F, Haghshenas P, Huestis MP, Hsu PL, Kou P, Jakalian A, Larouche-Gauthier R, Leclerc JP, Leung DH, Martin A, Murray J, Prangley M, Rutz S, Kakiuchi-Kiyota S, Satz AL, Skelton NJ, Steffek M, Stoffler D, Sudhamsu J, Tan S, Wang J, Wang S, Wang Q, Wendorff TJ, Wichert M, Yadav A, Yu C, Wang X ACS Med Chem Lett. 2024 May 29;15(6):864-872. doi: , 10.1021/acsmedchemlett.4c00068. eCollection 2024 Jun 13. PMID:38894924<ref>PMID:38894924</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8vw5" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Hsu PL]]
[[Category: Murray J]]
[[Category: Yu C]]