1A8Y

CRYSTAL STRUCTURE OF CALSEQUESTRIN FROM RABBIT SKELETAL MUSCLE SARCOPLASMIC RETICULUM AT 2.4 A RESOLUTION

Summary for 1A8Y

• Entry DOI: 10.2210/pdb1a8y/pdb
• Descriptor: CALSEQUESTRIN (2 entities in total)
• Functional Keywords: calsequestrin, calcium-binding protein, sarcoplasmic reticulum, rabbit skeletal muscle
• Biological source: Oryctolagus cuniculus (rabbit)
• Total number of polymer chains: 1
• Total formula weight: 42468.17

Authors

Wang, S.,Trumble, W.R.,Liao, H.,Wesson, C.R.,Dunker, A.K.,Kang, C. (deposition date: 1998-03-31, release date: 1999-03-30, Last modification date: 2024-02-07)

Primary citation

Wang, S.,Trumble, W.R.,Liao, H.,Wesson, C.R.,Dunker, A.K.,Kang, C.H.
Crystal structure of calsequestrin from rabbit skeletal muscle sarcoplasmic reticulum.
Nat.Struct.Biol., 5:476-483, 1998

PubMed Abstract: Calsequestrin, the major Ca2+ storage protein of muscle, coordinately binds and releases 40-50 Ca2+ ions per molecule for each contraction-relaxation cycle by an uncertain mechanism. We have determined the structure of rabbit skeletal muscle calsequestrin. Three very negative thioredoxin-like domains surround a hydrophilic center. Each monomer makes two extensive dimerization contacts, both of which involve the approach of many negative groups. This structure suggests a mechanism by which calsequestrin may achieve high capacity Ca2+ binding. The suggested mechanism involves Ca2+-induced collapse of the three domains and polymerization of calsequestrin monomers arising from three factors: N-terminal arm exchange, helix-helix contacts and Ca2+ cross bridges. This proposed structure-based mechanism accounts for the observed coupling of high capacity Ca2+ binding with protein precipitation.

PubMed: 9628486
DOI: 10.1038/nsb0698-476

Experimental method

X-RAY DIFFRACTION (2.4 Å)