Cylicin-2 (CYLC2)

Cylicin-2 (CYLC2) is a testis-specific cytoskeletal protein uniquely expressed during the process of spermiogenesis in mammals[1][2][3]. It is a highly basic protein, mainly present in the calyx region of the perinuclear theca at the posterior part of mature sperm nuclei[1][2][3]. Cylicin-2, together with its paralog Cylicin-1, is required for proper assembly and structural integrity of the sperm head, especially supporting the architecture required for normal acrosome formation and attachment[1][2][3]. Genetic disruption of the CYLC2 gene in mice leads to infertility characterized by malformed sperm due to defects in calyx structure, loss of perinuclear theca integrity, improper acrosome attachment, and faulty removal of excess cytoplasm[1][2]. Variants in CYLC2 have also been identified in infertile men with severely abnormal sperm morphology[1].\nWhile CYLC2 is essential for sperm development and male fertility, it is not currently considered a therapeutic target like a receptor or enzyme[1][2][3]. There are currently no known drugs, biomarker applications, or safety/efficacy issues associated with targeting this protein, and its relevance is primarily structural and not pharmacological[1][2][3].

Other names

Cylicin-2CYLC2CYL2Cylicin IIMultiple-band polypeptide IIcylicin-2cylicin IIcylicinbasic protein of sperm head cytoskeleton 2multiple-band polypeptide II