There is considerable rearrangement and lengthening of the "linker" region of cTnC, residues 87 through 97 upon phosphorylation. This has an effect on the disposition of the NcTnC domain relative to the CcTnC domain, with the two domains becoming closer. There are also changes in the interaction of the CcTnT and the EF3 and 4 hands of CcTnC resulting in the close coupling of the CcTnT and CcTnC.