Sperm-associated antigen 1 (SPAG1)

Sperm-associated antigen 1 (SPAG1) is a cytoskeletal-associated GTPase protein encoded by the SPAG1 gene located on chromosome 8q22.2. It was originally identified as a component of the sperm tail and is involved in the structural integrity and motility of spermatozoa[2][3]. SPAG1 binds GTP and possesses GTPase activity, playing a key role in the regulation of GTP-mediated signal transduction pathways important for spermatogenesis and fertilization[3][4]. It is also implicated in the cytoplasmic assembly of ciliary dynein arms and is necessary for meiotic progression in germ cells[3]. SPAG1 has clinical significance outside reproduction, with high expression levels observed in several cancers, including breast cancer, where it promotes tumor cell proliferation and is associated with worse prognosis[1]. Mutations in SPAG1 are linked to primary ciliary dyskinesia (a ciliopathy, CILD28) and certain forms of epilepsy[3]. SPAG1 is being studied both as a potential biomarker for infertility and cancer prognosis and as an immunogen in autoimmunity or contraception research[1][2][4].

Other names

SPAG1CILD28CT140HSD-3.8SP75TPISHEL-S-268DNAAF13