IUBMB Enzyme Nomenclature


Accepted name: oviductin

Reaction: Preferential cleavage at Gly-Ser-Arg373 of glycoprotein gp43 in Xenopus laevis coelemic egg envelope to yield gp41

Other name(s): oviductal protease

Comments: The egg envelope of the South African clawed frog (Xenopus laevis) is modified during transit of the egg through the pars rectus oviduct, changing the egg envelope from an unfertilizable form to a fertilizable form. This process involves the conversion of glycoprotein p43 to p41 by the pars recta protease oviductin. It is thought that the enzymatically active protease molecule comprises the N-terminal protease domain coupled to two C-terminal CUB domains, which are related to the mammalian spermadhesin molecules implicated in mediating sperm-envelope interactions [2]. The enzyme is also found in the Japanese toad (Bufo japonicus) [3]. Belongs in peptidase family S1.

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, CAS registry number: 342900-44-1


1. Hardy, D.M. and Hedrick, J.L. Oviductin. Purification and properties of the oviductal protease that processes the molecular weight 43,000 glycoprotein of the Xenopus laevis egg envelope. Biochemistry 31 (1992) 4466-4472. [PMID: 1581303]

2. Lindsay, L.L., Wieduwilt, M.J. and Hedrick, J.L. Oviductin, the Xenopus laevis oviductal protease that processes egg envelope glycoprotein gp43, increases sperm binding to envelopes, and is translated as part of an unusual mosaic protein composed of two protease and several CUB domains. Biol. Reprod. 60 (1999) 989-995. [PMID: 10084976]

3. Hiyoshi, M., Takamune, K., Mita, K., Kubo, H., Sugimoto, Y. and Katagiri, C. Oviductin, the oviductal protease that mediates gamete interaction by affecting the vitelline coat in Bufo japonicus: its molecular cloning and analyses of expression and posttranslational activation. Dev. Biol. 243 (2002) 176-184. [PMID: 11846486]

[EC created 2007]

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