Bio Background |
Creatine kinase (CK1) plays an important role transferring phosphate groups from phosphocreatine to ADP in the cytosol of tissues having high, fluctuating energy demands like skeletal muscle, heart, and brain. Mitochondrial CK1, CK1Mt, has two isoforms, sarcomeric CK1Mt and ubiquitous CK1Mt. CK1Mt is localized between the MIM (mitochondrial inner membrane) and MOM (mitochondrial outer membrane) and bound to the cardiolipin-rich inner leaflet (Muller et al., 1985) and along the cristae membranes (Wegmann et al., 1991). CK1Mt exists in two forms; a homo dimer and an octamer consisting of four homodimers. The CK1Mt octamer forms permanent contact sites and maintains a complex structure including porin and ANT (adenine nucleotide translocase) within MIM and MOM (Speer et al, 2005). There have been several phospho-serine, threonine, and tyrosine sites identified within CK1Mt, the role of each one has yet to be determined. |