X-ray structure of a human cardiac muscle troponin C/troponin I chimera in two crystal forms.

Chunhong Yan, John S Sack

Acta crystallographica. Section F, Structural biology communications 2022 Jan 01

filter terms:

The X-ray crystal structure of a human cardiac muscle troponin C/troponin I chimera has been determined in two different crystal forms and shows a conformation of the complex that differs from that previously observed by NMR. The chimera consists of the N-terminal domain of troponin C (cTnC; residues 1-80) fused to the switch region of troponin I (cTnI; residues 138-162). In both crystal forms, the cTnI residues form a six-turn α-helix that lays across the hydrophobic groove of an adjacent cTnC molecule in the crystal structure. In contrast to previous models, the cTnI helix runs in a parallel direction relative to the cTnC groove and completely blocks the calcium desensitizer binding site of the cTnC-cTnI interface.

Citation

Chunhong Yan, John S Sack. X-ray structure of a human cardiac muscle troponin C/troponin I chimera in two crystal forms. Acta crystallographica. Section F, Structural biology communications. 2022 Jan 01;78(Pt 1):17-24