Defensin Beta 121 (DEFb121)

Defensins are members of a large diverse family of cationic antimicrobial peptides that share a signature pattern consisting of six conserved cysteine residues. Defensins have a wide variety of functions and their disruption has been implicated in various human diseases.The genomic structures of DEFB121 and DEFB122 were determined in silico. Sequences of the five macaque orthologs were obtained and expression patterns of the genes were analyzed in humans and macaque by semiquantitative reverse transcription polymerase chain reaction. Expression was restricted to the male reproductive tract. Evolutionary analyses suggest that this cluster originated by a series of duplication events and by positive selection. The evolutionary forces driving the proliferation and diversification of these defensins may be related to reproductive specialization and/or the host–parasite coevolutionary process.