CABYR Proteins

Protein Information

Spermatozoa gain fertilization capacitation and hyperactivation after residing in the uterus or oviduct. Calcium, cAMP and protein tyrosine phosphorylation are necessary for the molecular mechanisms that allow for this transformation. CABYR (Calcium-binding tyrosine phosphorylation-regulated protein), also known as Fibrousheathin-2 or Cancer/testis antigen 88, is a 493 amino acid protein that is expressed in sperm flagella and exhibits increased tyrosine phosphorylation during capacitation. There are six named isoforms of CABYR that are produced as a result of alternative slicing events. Specifically, isoform 1 is expressed in the testis, while isoform 3 and isoform 5 are expressed in pancreas, brain and various brain tumors. Isoforms 1, 2 and 6 most likely bind calcium, whereas isoforms 3, 4 and 5 probably do not bind calcium.

Synonyms

1700016C01Rik; 4933421A18Rik; Cabyr; CABYRa; CABYRc; CABYRc/d; CABYRe; calcium binding tyrosine phosphorylation regulated; calcium binding tyrosine-(Y)-phosphorylation regulated; calcium binding tyrosine-(Y)-phosphorylation regulated (fibrousheathin 2); calcium-binding protein 86; Calcium-binding tyrosine phosphorylation-regulated protein; calcium-binding tyrosine-(Y)-phosphorylation regulated (fibrousheathin 2); calcium-binding tyrosine-phosphorylation regulated protein; cancer/testis antigen 88; CBP86; CT88; fibrousheathin 2; fibrousheathin II; Fibrousheathin-2; FSP2; FSP-2; testis tissue sperm-binding protein Li 84P; Testis-specific calcium-binding protein CBP86