ジャーナル: Structure / 年: 2013 タイトル: Structural insights into the intrinsic self-assembly of Par-3 N-terminal domain. 著者: Yan Zhang / Wenjuan Wang / Jia Chen / Kai Zhang / Feng Gao / Bingquan Gao / Shuai Zhang / Mingdong Dong / Flemming Besenbacher / Weimin Gong / Mingjie Zhang / Fei Sun / Wei Feng / 要旨: Par-3, the central organizer of the Par-3/Par-6/atypical protein kinase C complex, is a multimodular scaffold protein that is essential for cell polarity establishment and maintenance. The N-terminal ...Par-3, the central organizer of the Par-3/Par-6/atypical protein kinase C complex, is a multimodular scaffold protein that is essential for cell polarity establishment and maintenance. The N-terminal domain (NTD) of Par-3 is capable of self-association to form filament-like structures, although the underlying mechanism is poorly understood. Here, we determined the crystal structure of Par-3 NTD and solved the filament structure by cryoelectron microscopy. We found that an intrinsic "front-to-back" interaction mode is important for Par-3 NTD self-association and that both the lateral and longitudinal packing within the filament are mediated by electrostatic interactions. Disruptions of the lateral or longitudinal packing significantly impaired Par-3 NTD self-association and thereby impacted the Par-3-mediated epithelial polarization. We finally demonstrated that a Par-3 NTD-like domain from histidine ammonia-lyase also harbors a similar self-association capacity. This work unequivocally provides the structural basis for Par-3 NTD self-association and characterizes one type of protein domain that can self-assemble via electrostatic interactions.
This protein forms helical filament in solution. Cryo-electron microscopic reconstruction revealed that the dimer in the crystallographic asymmetric unit is the same as the building block of the helical filament.
解像度: 2.9→39.94 Å / Cor.coef. Fo:Fc: 0.918 / Cor.coef. Fo:Fc free: 0.86 / SU B: 19.255 / SU ML: 0.35 / 交差検証法: THROUGHOUT / σ(F): 0 / ESU R: 1.008 / ESU R Free: 0.415 / 立体化学のターゲット値: MAXIMUM LIKELIHOOD / 詳細: HYDROGENS HAVE BEEN USED IF PRESENT IN THE INPUT
Rfactor
反射数
%反射
Selection details
Rfree
0.29361
301
4.7 %
RANDOM
Rwork
0.23005
-
-
-
obs
0.23296
6058
96.33 %
-
all
-
6289
-
-
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK