A disintegrin & metalloproteinase domain 21 (ADAM21)

Function

• may be involved in sperm maturation &/or fertilization
• may also be involved in epithelia functions
• associated with establishing & maintaining gradients of ions or nutrients
• no obvious cleavage site for furin endopeptidase, suggesting that the proteolytic processing is regulated

Cofactor: binds 1 Zn+2 per subunit (putative)

Structure

• a tripeptide motif (VGE) within disintegrin-like domain could be involved in binding to egg integrin receptor & thus could mediate sperm/egg binding
• cysteine-rich domain encodes putative cell-fusion peptides, which could be involved in sperm-egg fusion
• conserved Cys present in the cysteine-switch motif binds the catalytic Zn+2, thus inhibiting the enzyme
• dissociation of Cys from Zn+2 upon activation- peptide release activates the enzyme
• contains 1 disintegrin domain
• contains 1 EGF-like domain
• contains 1 peptidase M12B domain

Compartment

membrane

Notes

• may be the functional equivalent of fertilin alpha (ADAM1) which is a pseudogene in human

More general terms

• ADAM protease
• glycoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=8747
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:8747
• OMIM: https://mirror.omim.org/entry/603713
• UniProt: http://www.uniprot.org/uniprot/Q9UKJ8.html