Spermatid nuclear transition protein 1 is a protein that in humans is encoded by the TNP1 gene. Transition protein-1 is a spermatid-specific product of the haploid genome which replaces histone and is itself replaced in the mature sperm by the protamines (see PRM1, MIM 182880; PRM2, MIM 182890) (Luerssen et al., 1990 [PubMed 2249851]).[supplied by OMIM]. Sequence Note: removed 4 bases from the 5' end that did not align to the reference genome assembly. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Gene record to access additional publications.
Function: In the elongating spermatids of mammals, the conversion of nucleosomal chromatin to the compact, non-nucleosomal form found in the sperm nucleus is associated with the appearance of a small set of basic chromosomal transition proteins.