TXNRD1

{{Short description|Protein-coding gene in the species Homo sapiens}}

{{Infobox_gene}}

Thioredoxin reductase 1, cytoplasmic is an enzyme that in humans is encoded by the TXNRD1 gene.{{cite journal | vauthors = Gasdaska PY, Gasdaska JR, Cochran S, Powis G | title = Cloning and sequencing of a human thioredoxin reductase | journal = FEBS Lett | volume = 373 | issue = 1 | pages = 5–9 |date=Nov 1995 | pmid = 7589432 | doi = 10.1016/0014-5793(95)01003-W| s2cid = 735874 | doi-access = free }}

This gene encodes a member of the family of pyridine nucleotide oxidoreductases. This protein reduces thioredoxins as well as other substrates, and plays a role in selenium metabolism and protection against oxidative stress. The functional enzyme is thought to be a homodimer which uses FAD as a cofactor. Each subunit contains a selenocysteine (Sec) residue which is required for catalytic activity. The selenocysteine is encoded by the UGA codon that normally signals translation termination. The 3' UTR of selenocysteine-containing genes have a common stem-loop structure, the sec insertion sequence (SECIS), that is necessary for the recognition of UGA as a Sec codon rather than as a stop signal. Alternative splicing results in several transcript variants encoding the same or different isoforms.{{cite web | title = Entrez Gene: TXNRD1 thioredoxin reductase 1| url = https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=7296}}