Serine Peptidase Inhibitor Like, With Kunitz And WAP Domains 1 (SPINLW1)

SPINLW1 contains an N-terminal secretory signal sequence, a central Kunitz-type sequence, and a C-terminal WAP-type sequence, as well as 14 cysteine residues. The EPPIN2 transcript differs from EPPIN1 and EPPIN3 in the 5-prime UTR and in a short part of the N-terminal coding region. The deduced 117-amino acid EPPIN2 protein has a calculated molecular mass of 13.5 kD. It contains the 2 protease inhibitor consensus sequences, but lacks the N-terminal secretory signal sequence. Northern blot analysis detected EPPIN1 expressed as a single band in epididymis and as 2 bands in testis, but not in any other tissue examined. PCR using transcript-specific primers detected EPPIN1 in testis and epididymis, EPPIN2 only in epididymis, and EPPIN3 only in testis.