Defensin Beta 118 (DEFb118)

ESC42 has a signal peptide and a cysteine-rich N-terminal half containing a CCHC-type DNA-binding zinc finger and an epidermal growth factor (EGF)-like 3-loop trefoil domain. There is an N-glycosylation site and several putative phosphorylation sites. ESC42 has a calculated molecular mass of 11.2 kD after signal peptide removal. Northern blot analysis of diverse rhesus monkey tissues detected ESC42 expression only in epididymis. Western blot analysis detected a protein of about 20 kD in human ejaculated sperm. COS-1 cells transfected with rhesus ESC42 detected a protein of 18.5 kD and several multimeric species with higher molecular masses. Immunohistochemical localization of ESC42 in monkey epididymis detected abundant protein in epithelial cells of the caput, in efferent duct epithelial cells, and in sperm.