Acrosin, the peculiar sperm-specific serine protease.pdfVIP

Hum Genet (1991) 87:635-641 9 Springer-Verlag 1991 Review article Acrosin, the peculiar sperm-specific serine protease Uwe Klemm I, Werner Miiller-Esterl 2, and Wolfgang Engel 1 l Institut for Humangenetik der Universitfit, Gosslerstrasse 12d, W-3400 G6ttingen, Federal Republic of Germany 2Institut for Physiologische Chemie und Pathobiochemie der Universit~it, Duesbergweg 6, W-6500 Mainz, Federal Republic of Germany Received January 8, 1991 / Revised April 10, 1991 Summary. The sperm enzyme acrosin has long been known as one of the key enzymes in the mammalian fer- tilization process. Elucidation of primary structures of preproacrosin from various species have allowed a deeper insight into the structural organization and the complex evolution of the sperm proteinase acrosin. In addition to the typical elements of serine proteases, the acrosin mol- ecule possesses one novel domain that might convey DNA-binding properties. Introduction The long history of the study of proteolytic enzymes of the sperm cell was initiated in 1935 by a report of Yamane (Yamane 1935), describing the solubilizing effect of rab- bit sperm extracts on the outer investments of oocytes. These findings stimulated the isolation and purification of sperm enzymes in the following decades. Many inves- tigators focused on the major component of the ac- rosomal content, a trypsin-like enzyme called acrosin (EC 3.4.21.10) (Zaneveld et al. 1971). Following de- tailed analysis with natural and artifical substrates and inhibitors (Stambaugh and Buckley 1968), acrosin was classified as a member of the serine protease superfam- ily. This classification was supported by limited amino acid sequence information from boar (Fock-Ntizel et al. 1980, 1984) and goat acrosin (Hardy et al. 1989) ob- tained by the classical Edmann degradation method. Using the methods of recombinant DNA technology, difficulties in protein sequencing were bypassed and the primary structures for huma