Troponin Cis a protein which is part of thetroponincomplex. It contains four calcium-bindingEF hands,although different isoforms may have fewer than four functional calcium-binding subdomains. It is a component ofthin filaments,along withactinandtropomyosin.It contains an N lobe and a C lobe. The C lobe serves a structural purpose and binds to the N domain oftroponin I(TnI). The C lobe can bind either Ca2+or Mg2+.The N lobe, which binds only Ca2+,is the regulatory lobe and binds to the C domain of troponin I after calcium binding.
Point mutations can occur in troponin C inducing alterations to Ca2+and Mg2+binding and protein structure,[1]leading to abnormalities in muscle contraction.[2][3]In cardiac muscle, they are related todilated cardiomyopathy(DCM) andhypertrophic cardiomyopathy(HCM).
^Kalyva A, Parthenakis FI, Marketou ME, Kontaraki JE, Vardas PE (April 2014). "Biochemical characterisation of Troponin C mutations causing hypertrophic and dilated cardiomyopathies".Journal of Muscle Research and Cell Motility.35(2): 161–78.doi:10.1007/s10974-014-9382-0.PMID24744096.S2CID1726747.
