CBR1
Description
The CBR1 (carbonyl reductase 1) is a protein-coding gene located on chromosome 21.
Carbonyl reductase 1, also known as CBR1, is an enzyme which in humans is encoded by the CBR1 gene. The protein encoded by this gene belongs to the short-chain dehydrogenases/reductases (SDR) family, which function as NADPH-dependent oxidoreductases having wide specificity for carbonyl compounds, such as quinones, prostaglandins, and various xenobiotics. Alternatively spliced transcript variants have been found for this gene. Carbonyl reductase is one of several monomeric, NADPH-dependent oxidoreductases having wide specificity for carbonyl compounds. This enzyme is widely distributed in human tissues. Another carbonyl reductase gene, CBR3, lies close to this gene on chromosome 21q22.12. CBR1 metabolizes many toxic environmental quinones and pharmacological relevant substrates such as the anticancer doxorubicin. Several studies have shown that CBR1 plays a protective role in oxidative stress, neurodegeneration, and apoptosis. In addition, CBR1 inactivates lipid aldehydes during oxidative stress in cells. Therefore, CBR1 may play a beneficial role in protecting against cellular damage resulting from oxidative stress.
CBR1 is an NADPH-dependent reductase with broad substrate specificity. It catalyzes the reduction of a wide variety of carbonyl compounds, including quinones, prostaglandins, menadione, and various xenobiotics. It also catalyzes the reduction of the antitumor anthracyclines doxorubicin and daunorubicin to the cardiotoxic compounds doxorubicinol and daunorubicinol. CBR1 can convert prostaglandin E to prostaglandin F2-alpha. It can bind glutathione, which explains its higher affinity for glutathione-conjugated substrates. CBR1 catalyzes the reduction of S-nitrosoglutathione. In addition, it participates in the glucocorticoid metabolism by catalyzing the NADPH-dependent cortisol/corticosterone into 20beta-dihydrocortisol (20b-DHF) or 20beta-corticosterone (20b-DHB), which are weak agonists of NR3C1 and NR3C2 in adipose tissue.
CBR1 is also known as CBR, PG-9-KR, SDR21C1, hCBR1.
