View source for 8fd9


==Structure of BTK kinase domain with the second-generation inhibitor acalabrutinib==
<StructureSection load='8fd9' size='340' side='right'caption='[[8fd9]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8fd9]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8FD9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8FD9 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]] 1.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BR:BROMIDE+ION'>BR</scene>, <scene name='pdbligand=XQQ:4-[8-azanyl-3-[(2~{S})-1-[(~{E})-but-2-enoyl]pyrrolidin-2-yl]imidazo[1,5-a]pyrazin-1-yl]-~{N}-pyridin-2-yl-benzamide'>XQQ</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=8fd9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8fd9 OCA], [https://pdbe.org/8fd9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8fd9 RCSB], [https://www.ebi.ac.uk/pdbsum/8fd9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8fd9 ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/BTK_MOUSE BTK_MOUSE] Defects in Btk are the cause of murine X-linked immunodeficiency (XID).
== Function ==
[https://www.uniprot.org/uniprot/BTK_MOUSE BTK_MOUSE] Non-receptor tyrosine kinase indispensable for B lymphocyte development, differentiation and signaling. Binding of antigen to the B-cell antigen receptor (BCR) triggers signaling that ultimately leads to B-cell activation. After BCR engagement and activation at the plasma membrane, phosphorylates PLCG2 at several sites, igniting the downstream signaling pathway through calcium mobilization, followed by activation of the protein kinase C (PKC) family members. PLCG2 phosphorylation is performed in close cooperation with the adapter protein B-cell linker protein BLNK. BTK acts as a platform to bring together a diverse array of signaling proteins and is implicated in cytokine receptor signaling pathways. Plays an important role in the function of immune cells of innate as well as adaptive immunity, as a component of the Toll-like receptors (TLR) pathway. The TLR pathway acts as a primary surveillance system for the detection of pathogens and are crucial to the activation of host defense. Especially, is a critical molecule in regulating TLR9 activation in splenic B-cells. Within the TLR pathway, induces tyrosine phosphorylation of TIRAP which leads to TIRAP degradation. BTK plays also a critical role in transcription regulation. Induces the activity of NF-kappa-B, which is involved in regulating the expression of hundreds of genes. BTK is involved on the signaling pathway linking TLR8 and TLR9 to NF-kappa-B. Transiently phosphorylates transcription factor GTF2I on tyrosine residues in response to BCR. GTF2I then translocates to the nucleus to bind regulatory enhancer elements to modulate gene expression. ARID3A and NFAT are other transcriptional target of BTK. BTK is required for the formation of functional ARID3A DNA-binding complexes. There is however no evidence that BTK itself binds directly to DNA. BTK has a dual role in the regulation of apoptosis.<ref>PMID:10852954</ref> <ref>PMID:11120822</ref> <ref>PMID:16738337</ref> <ref>PMID:17725607</ref> <ref>PMID:7538439</ref> <ref>PMID:8629002</ref> 
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== Publication Abstract from PubMed ==
Bruton's tyrosine kinase (BTK) is the target of the therapeutic agent, Ibrutinib, that treats chronic lymphocyte leukemia (CLL), mantle cell lymphoma (MCL) and other B cell malignancies. Ibrutinib is a first in class, covalent BTK inhibitor that limits B-cell survival and proliferation. Designing new inhibitors of BTK has been an important objective for advancing development of improved therapeutic agents against cancer and autoimmune disorders. Based on the success of Ibrutinib, several second-generation irreversible BTK inhibitors have been developed that exhibit fewer off-target effects. However, the binding-mode and their interaction with Btk have not been experimentally determined and evaluated at atomic resolution. Here we determined the first crystal structure of the BTK kinase domain in complex with acalabrutinib. In addition, we report a structure of the BTK/tirabrutinib complex and compare these structures with previously solved structures. The structures provide insight in the superior selectivity reported for acalabrutinb and guide future BTK inhibitor development.

Structure of BTK kinase domain with the second-generation inhibitors acalabrutinib and tirabrutinib.,Lin DY, Andreotti AH PLoS One. 2023 Aug 31;18(8):e0290872. doi: 10.1371/journal.pone.0290872. , eCollection 2023. PMID:37651403<ref>PMID:37651403</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 8fd9" style="background-color:#fffaf0;"></div>

==See Also==
*[[Tyrosine kinase 3D structures|Tyrosine kinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Andreotti AH]]
[[Category: Lin DY]]