The common marmoset (Callithrix jacchus) as a model for histone and protamine expression during human spermatogenesis

conclusions: The common marmoset represents a suitable animal model for studies on nuclear protein expression during human spermatogenesis. The two species exhibit a similar organization of seminiferous epithelium and an identical expression pattern of protamine-1 and protamine-2 mRNA in round and elongating spermatids. The presence of specifically acetylated histones H4 in testicular spermatids and ejaculated spermatozoa demonstrates an incomplete histone to protamine exchange in both species. As acetylated histones are known to be associated with genes involved in gene expression, the common marmoset may, in future, be used as a model for investigations on early embryo development which, in man, are not possible for ethical reasons.