气候变化领域集成服务门户(CCPortal): A symmetric geometry of transmembrane domains inside the B cell antigen receptor complex

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DOI	10.1073/pnas.1907481116
	A symmetric geometry of transmembrane domains inside the B cell antigen receptor complex
	Gottwick C.; He X.; Hofmann A.; Vesper N.; Reth M.; Yang J.
发表日期	2019
ISSN	0027-8424
起始页码	13468
结束页码	13473
卷号	116 期号:27
英文摘要	B lymphocytes have the ability to sense thousands of structurally different antigens and produce cognate antibodies against these molecules. For this they carry on their surface multiple copies of the B cell antigen receptor (BCR) comprising the membrane-bound Ig (mIg) molecule and the Igα/Igβ heterodimer functioning as antigen binding and signal transducing components, respectively. The mIg is a symmetric complex of 2 identical membrane-bound heavy chains (mHC) and 2 identical light chains. How the symmetric mIg molecule is asymmetrically associated with only one Igα/Igβ heterodimer has been a puzzle. Here we describe that Igα and Igβ both carry on one side of their α-helical transmembrane domain a conserved amino acid motif. By a mutational analysis in combination with a BCR rebuilding approach, we show that this motif is required for the retention of unassembled Igα or Igβ molecules inside the endoplasmic reticulum and the binding of the Igα/Igβ heterodimer to the mIg molecule. We suggest that the BCR forms within the lipid bilayer of the membrane a symmetric Igα-mHC:mHC-Igβ complex that is stabilized by an aromatic proline-tyrosine interaction. Outside the membrane this symmetry is broken by the disulfide-bridged dimerization of the extracellular Ig domains of Igα and Igβ. However, symmetry of the receptor can be regained by a dimerization of 2 BCR complexes as suggested by the dissociation activation model. © 2019 National Academy of Sciences. All rights reserved.
英文关键词	Assembly; B cell antigen receptor; ER retention; Symmetry
语种	英语
scopus关键词	B lymphocyte antigen; B lymphocyte receptor; CRISPR associated endonuclease Cas9; immunoglobulin G; lymphocyte antigen receptor; animal cell; Article; binding affinity; controlled study; CRISPR-CAS9 system; cytokine production; disulfide bond; flow cytometry; genetic procedures; hydrophobicity; lipid bilayer; mutagenesis; mutational analysis; nonhuman; phenotype; plasmid; priority journal; protein analysis; protein binding; protein domain; protein function; protein motif; protein protein interaction; protein stability; signal transduction; site directed mutagenesis
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160393
作者单位	Gottwick, C., BIOSS Centre For Biological Signaling Studies, Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany; He, X., BIOSS Centre For Biological Signaling Studies, Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany, Department of Molecular Immunology, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, 79108, Germany; Hofmann, A., BIOSS Centre For Biological Signaling Studies, Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany, Department of Molecular Immunology, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, 79108, Germany; Vesper, N., BIOSS Centre For Biological Signaling Studies, Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany; Reth, M., BIOSS Centre For Biological Signaling Studies, Department of Mole...
推荐引用方式 GB/T 7714	Gottwick C.,He X.,Hofmann A.,et al. A symmetric geometry of transmembrane domains inside the B cell antigen receptor complex[J],2019,116(27).
APA	Gottwick C.,He X.,Hofmann A.,Vesper N.,Reth M.,&Yang J..(2019).A symmetric geometry of transmembrane domains inside the B cell antigen receptor complex.Proceedings of the National Academy of Sciences of the United States of America,116(27).
MLA	Gottwick C.,et al."A symmetric geometry of transmembrane domains inside the B cell antigen receptor complex".Proceedings of the National Academy of Sciences of the United States of America 116.27(2019).