From Proteopedia

proteopedia linkproteopedia link

spinqualitylabelsall models 3ctn Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

STRUCTURE OF CALCIUM-SATURATED CARDIAC TROPONIN C, NMR, 30 STRUCTURES

Overview

The regulation of cardiac muscle contraction must differ from that of, skeletal muscles to effect different physiological and contractile, properties. Cardiac troponin C (TnC), the key regulator of cardiac muscle, contraction, possesses different functional and Ca2+-binding properties, compared with skeletal TnC and features a Ca2+-binding site I, which is, naturally inactive. The structure of cardiac TnC in the Ca2+-saturated, state has been determined by nuclear magnetic resonance spectroscopy. The, regulatory domain exists in a "closed" conformation even in the Ca2+-bound, (the "on") state, in contrast to all predicted models and differing, significantly from the calcium-induced structure observed in skeletal TnC., This structure in the Ca2+-bound state, and its subsequent interaction, with troponin I (TnI), are crucial in determining the specific regulatory, mechanism for cardiac muscle contraction. Further, it will allow for an, understanding of the action of calcium-sensitizing drugs, which bind to, cardiac TnC and are known to enhance the ability of cardiac TnC to, activate cardiac muscle contraction.

About this Structure

3CTN is a Single protein structure of sequence from Gallus gallus with CA as ligand. Full crystallographic information is available from OCA.

Reference

Structure of cardiac muscle troponin C unexpectedly reveals a closed regulatory domain., Sia SK, Li MX, Spyracopoulos L, Gagne SM, Liu W, Putkey JA, Sykes BD, J Biol Chem. 1997 Jul 18;272(29):18216-21. PMID:9218458

Page seeded by OCA on Tue Nov 20 19:38:10 2007