1QLY

NMR Study of the SH3 Domain From Bruton's Tyrosine Kinase, 20 Structures

1QLY の概要

• エントリーDOI: 10.2210/pdb1qly/pdb
• 関連するPDBエントリー: 1AWW 1AWX 1BTK
• 分子名称: TYROSINE-PROTEIN KINASE BTK (1 entity in total)
• 機能のキーワード: transferase, tyrosine-protein kinase, phosphorylation, sh3 domain
• 由来する生物種: HOMO SAPIENS (HUMAN)
• 細胞内の位置: Cytoplasm (By similarity): Q06187
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 6890.70

構造登録者

Tzeng, S.R.,Lou, Y.C.,Pai, M.T.,Chen, C.,Chen, S.H.,Cheng, J.Y. (登録日: 1999-09-20, 公開日: 1999-12-14, 最終更新日: 2024-05-15)

主引用文献

Tzeng, S.R.,Lou, Y.C.,Pai, M.T.,Chen, C.P.,Chen, S.H.,Cheng, J.W.
Solution Structure of the Human Btk SH3 Domain Complexed with a Proline-Rich Peptide from P120Cbl
J.Biomol.NMR, 16:303-, 2000

PubMed Abstract: X-linked agammaglobulinemia (XLA), an inherited disease, is caused by mutations in the Bruton's tyrosine kinase (BTK). The absence of functional BTK leads to failure of B cell differentiation which incapacitates antibody production in XLA patients leading to, sometimes lethal, bacterial infections. Point mutation in the BTK gene that leads to deletion of C-terminal 14 aa residues of BTK SH3 domain was found in one patient family. To understand the role of BTK in B cell development, we have determined the solution structure of BTK SH3 domain complexed with a proline-rich peptide from the protein product of c-cbl protooncogene (p120cbl). Like other SH3 domains, BTK SH3 domain consists of five beta-strands packed in two beta-sheets forming a beta-barrel-like structure. The rmsd calculated from the averaged coordinates for the BTK SH3 domain residues 218-271 and the p120cbl peptide residues 6-12 of the complex was 0.87 A (+/-0.16 A) for the backbone heavy atoms (N, C, and Calpha) and 1.64 A (+/-0.16 A) for all heavy atoms. Based on chemical shift changes and inter-molecular NOEs, we have found that the residues located in the RT loop, n-Src loop and helix-like loop between beta4 and beta5 of BTK SH3 domain are involved in ligand binding. We have also determined that the proline-rich peptide from p120cbl binds to BTK SH3 domain in a class I orientation. These results correlate well with our earlier observation that the truncated BTK SH3 domain (deletion of beta4, beta5 and the helix-like loop) exhibits weaker affinity for the p120cbl peptide. It is likely that the truncated SH3 domain fails to present to the ligand the crucial residues in the correct context and hence the weaker binding. These results delineate the importance of the C-terminus in the binding of SH3 domains and also indicate that improper folding and the altered binding behavior of mutant BTK SH3 domain likely lead to XLA.

PubMed: 10826882
DOI: 10.1023/A:1008376624863

実験手法

SOLUTION NMR