The protein encoded by this gene, CK-BB, consists of a homodimer of two identical brain-type CK-B subunits. BB-CK is a cytoplasmic enzyme involved in cellular energy homeostasis, with certain fractions of the enzyme being bound to cell membranes, ATPases, and a variety of ATP-requiring enzymes in the cell. There, CK-BB forms tightly coupled microcompartments for in situ regeneration of ATP that has been used up. The encoded protein reversibly catalyzes the transfer of "energy-rich" phosphate between ATP and creatine or between phospho-creatine (PCr) and ADP. Its functional entity is a homodimer (CK-BB) in brain and smooth muscle as well as in other tissues and cells such as neuronal cells, retina, kidney, bone, etc. In heart, a heterodimer (CK-MB) shahil consisting of one CK-B brain-type CK subunit and one CK-M muscle-type CK subunit is prominently expressed. The encoded CK-BB and CK-MB proteins are members of the ATP:guanido phosphotransferase protein family.
^Bong SM, Moon JH, Nam KH, Lee KS, Chi YM, Hwang KY (November 2008). "Structural studies of human brain-type creatine kinase complexed with the ADP-Mg2+-NO3- -creatine transition-state analogue complex". FEBS Lett.582 (28): 3959–65. doi:10.1016/j.febslet.2008.10.039. PMID18977227.
^Kotz R, Leber H, Ramach W, Arbes H, Wolf A (July 1977). "[Clinical observations on the use of high-dose methotrexate treatment in osteogenic sarcoma (author's transl)]". Wien. Klin. Wochenschr. (in German) 89 (14): 474–9. PMID70889.
^Wienker TF, Ulferts A, Ott J, Bender K, Scheuerbrandt G, Arnold H, Ropers HH (1985). "A dominant mutation causing ectopic expression of the creatine kinase B gene maps on chromosome 14". Cytogenet. Cell Genet40: 776.