ACR, Official Symbol ACRprovided by HGNC Official Full Name acrosinprovided by HGNC Primary source HGNC:HGNC:126 See related Ensembl:ENSG00000100312 MIM:102480; AllianceGenome:HGNC:126 Gene type protein coding RefSeq status REVIEWED Organism Homo sapiens Lineage Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo Also known as SPGF87 Summary Acrosin is the major proteinase present in the acrosome of mature spermatozoa. It is a typical serine proteinase with trypsin-like specificity. It is stored in the acrosome in its precursor form, proacrosin. The active enzyme functions in the lysis of the zona pellucida, thus facilitating penetration of the sperm through the innermost glycoprotein layers of the ovum. The mRNA for proacrosin is synthesized only in the postmeiotic stages of spermatogenesis. In humans proacrosin first appears in the haploid spermatids. [provided by RefSeq, Jul 2008] Expression Restricted expression toward testis (RPKM 44.8) See more Orthologs mouse all