Electron microscopic evidence for a mucin‐like region in chick muscle α‐dystroglycan

FEBS Letters

Engel, Jürgen¹  Schulthess, Therese¹  Gesemann, Matthias²  Brancaccio, Andrea¹ 

[1] Department of Biophysical Chemistry, Biozentrum, University of Basel, Klingelbergstr. 70, CH 4056 Basel, Switzerland;Department of Pharmacology, Biozentrum, University of Basel, Klingelbergstr. 70, CH 4056 Basel, Switzerland

关键词: Dystroglycan;    Mucin;    Laminin;    Electron microscopy;    Chick muscle;   

DOI  :  10.1016/0014-5793(95)00628-M

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

α-Dystroglycan has been isolated from chicken cardiac muscle and its molecular weight was estimated to be ≈135 kDa. The avian protein interacts with murine Engelbreth-Holm-Swarm (EHS) tumor laminin via interaction with the C-terminal LG4 and LG5 domains (fragment E3) of the laminin α-chain. This laminin binding is calcium-dependent and can be competed by heparin. Electron microscopy investigation on the shape of α-dystroglycan suggests that the core protein consists of two roughly globular domains connected by a segment which most likely corresponds to a mucin-like central region also predicted by sequence analysis on mammalian isoforms. This segment may act as a spacer in the dystrophin-associated glycoproteins complex exposing the N-terminal domain of α-dystroglycan to laminin in the extracellular space.

【 授权许可】

Unknown