4HDI

Crystal Structure of 3E5 IgG3 FAB from mus musculus

4HDI の概要

• エントリーDOI: 10.2210/pdb4hdi/pdb
• 分子名称: Kappa light chain variable region, Anti-colorectal carcinoma light chain, Ig heavy chain V region RF, Ig gamma-3 chain C region (3 entities in total)
• 機能のキーワード: igg, fab, immune system
• 由来する生物種: Mus musculus (mouse); 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 95863.11

構造登録者

Janda, A.,Eryilmaz, E.,Kim, J.,Cordero, R.J.B.,Cowburn, D.,Casadevall, A. (登録日: 2012-10-02, 公開日: 2013-04-17, 最終更新日: 2024-10-09)

主引用文献

Eryilmaz, E.,Janda, A.,Kim, J.,Cordero, R.J.,Cowburn, D.,Casadevall, A.
Global structures of IgG isotypes expressing identical variable regions.
Mol.Immunol., 56:588-598, 2013

PubMed Abstract: Until relatively recently the immunoglobulin molecule was viewed as composed of two independent domains comprised of the variable (V) and constant (C) regions. However, recent work has established that the C region mediates allosteric changes in the V region that can influence specificity and affinity. To further explore cross-domain interrelationship in murine IgG structure we carried out solution small angle X-ray scattering (SAXS) measurements for four V region identical IgG isotypes. SAXS analysis revealed elongated Y-shaped structures in solution with significantly different, isotype-dependent domain orientations. To further explore local C region effects on the V region, the IgG₃ Fab crystal structure from the same family was determined to 2.45 Å resolution. The IgG₃ Fab crystal structure differs from a closely related previously solved IgG1 Fab revealing significant structural differences, which may account for isotype-related specificity differences in V region identical Abs. Among the four murine isotypes, IgG₃ was the most different in solution with regards to overall structure as well as aggregate formation in solution suggesting that the greater apparent affinity of this isotype resulted from polyvalent complexes with enhanced avidity. Our results provide additional evidence that Ig V and C domains influence each other structurally and suggest that V region structure can have significant effects on overall Ig structure.

PubMed: 23911417
DOI: 10.1016/j.molimm.2013.06.006

実験手法

X-RAY DIFFRACTION (2.449 Å)