thioredoxin reductase 3 (thioredoxin reductase TR2, thioredoxin & glutathione reductase, TXNRD3, TGR, TRXR3)

Function

• displays thioredoxin reductase, glutaredoxin & glutathione reductase activities
• catalyzes disulfide bond isomerization
• promotes disulfide bond formation between GPX4 & various sperm proteins & may play a role in sperm maturation by promoting formation of sperm structural components

thioredoxin + NADP+ <--> thioredoxin disulfide + NADPH

Cofactor: binds 1 FAD per subunit (putative)

Structure

• homodimer (putative)
• N-terminal glutaredoxin domain does not contain the C-X-X-C redox-active motif normally found in glutaredoxins but activity may be mediated through a single Cys
• C-terminal Cys-sec motif of one subunit of the homodimer may transfer electrons from the thiol-disulfide center to the glutaredoxin domain of the other subunit (putative)
• belongs to the class-1 pyridine nucleotide-disulfide oxidoreductase family
• contains 1 glutaredoxin domain
• thioredoxin reductase active site is a redox-active disulfide bond
• selenocysteine residue is also essential for catalytic activity (putative)

Compartment

• cytoplasm, nucleus, microsome (putative)
• detected in cytoplasm & nucleus in late spermatids (putative)

More general terms

• oxidoreductase

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:1141
• OMIM: https://mirror.omim.org/entry/606235
• UniProt: http://www.uniprot.org/uniprot/Q86VQ6.html