3KG5

Crystal structure of human Ig-beta homodimer

3KG5 の概要

• エントリーDOI: 10.2210/pdb3kg5/pdb
• 分子名称: B-cell antigen receptor complex-associated protein beta chain (2 entities in total)
• 機能のキーワード: cd79b, ig-beta, bcr, immunoglobulin domain, protein binding
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Cell membrane; Single-pass type I membrane protein: P40259
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 30999.10

構造登録者

Radaev, S.,Sun, P.D. (登録日: 2009-10-28, 公開日: 2010-08-25, 最終更新日: 2024-10-16)

主引用文献

Radaev, S.,Zou, Z.,Tolar, P.,Nguyen, K.,Nguyen, A.,Krueger, P.D.,Stutzman, N.,Pierce, S.,Sun, P.D.
Structural and Functional Studies of Igalphabeta and Its Assembly with the B Cell Antigen Receptor.
Structure, 18:934-943, 2010

PubMed Abstract: The B cell antigen receptor (BCR) plays an essential role in all phases of B cell development. Here we show that the extracellular domains of murine and human Igbeta form an I-set immunoglobulin-like structure with an interchain disulfide between cysteines on their G strands. Structural and sequence analysis suggests that Igalpha displays a similar fold as Igbeta. An Igalphabeta heterodimer model was generated based on the unique disulfide-bonded Igbeta dimer. Solution binding studies showed that the extracellular domains of Igalphabeta preferentially recognize the constant region of BCR with mu chain specificity, suggesting a role for Igalphabeta to enhance BCRmu chain signaling. Cluster mutations on Igalpha, Igbeta, and a membrane-bound form of immunoglobulin (mIgM) based on the structural model identified distinct areas of potential contacts involving charged residues on both subunits of the coreceptor and the Cmu4 domain of mIgM. These studies provide the first structural model for understanding BCR function.

PubMed: 20696394
DOI: 10.1016/j.str.2010.04.019

実験手法

X-RAY DIFFRACTION (3.2 Å)