Oviductins possess chitinase- and mucin-like domains: a lead in the search for the biological function of these oviduct-specific ZP-associating glycoproteins.

摘要: Over the last 10 years considerable progress has been made in immunological and biochemical characterization of oviduct-specific glycoproteins. It is now well established that a subclass these secretory products, designated as oviductins, associate with zona pellucida ovulated oocyte early embryo. Recent reports on cloning cDNAs oviductins from various species, including golden hamster (Mesocricetus auratus) oviductin by our laboratory, allowed us to compare their deduced amino acid sequences those other proteins. Optimal alignment analysis showed contain regions significant similarity catalytically inactive mammalian members bacterial microfilarial chitinase protein family. Most importantly, close examination human revealed both glycoproteins possess contiguous Ser/Thr rich repeated units, clustered carboxy-terminal portions. These mucin-type motifs are similar glycoprotein, although contains more complete units. This striking feature might indicate molecules play role glycoproteins, e.g., protecting embryo against attacks environment. We propose model whereby targeted via interaction chitinase-like domains specific oligosaccharide moieties pellucida. Once localized this structure, would act protective shield around virtue densely glycosylated domains. © 1995 Wiley-Liss, Inc.