BLVRB

Biliverdin reductase (hBVR) is a serine/threonine kinase that catalyzes reduction of the heme oxygenase (HO) activity product, biliverdin, to bilirubin. BVR consists of an N-terminal dinucleotide-binding domain (Rossmann-fold) and a C-terminal domain that contains a six-stranded β-sheet that is flanked on one face by several α-helices. The C-terminal and N-terminal domains interact extensively, forming the active site cleft at their interface. Biliverdin reductase (BVR) catalyzes the last step in heme degradation by reducing the γ-methene bridge of the open tetrapyrrole, biliverdin IXα, to bilirubin with the concomitant oxidation of a β-nicotinamide adenine dinucleotide (NADH) or β-nicotinamide adenine dinucleotide phosphate (NADPH) cofactor. It is now recognized that human BVR (hBVR) is a dual-specificity kinase (Ser / Thr and Tyr) upstream activator of the insulin/insulin growth factor-1 (IGF-1) and mitogen-activated protein kinase (MAPK) signaling pathways. Human BVR (hBVR) is essential for MAPK-extracellular signal-regulated kinase (ERK)1/2 (MEK)-eukaryotic-like protein kinase (Elk) signaling and has been identified as the cytoplasm-nuclear heme transporter of ERK1/2 and hematin, the key components of stress-responsive gene expression.

BLVRB Related Areas

Enzyme >>Protease & Regulator >>Serine Protease & Regulator >>Serpin Superfamily >>BLVRB

Enzyme>>Oxidoreductase>> BLVRB

BLVRB Alternative Names

BVRB, FLR, MGC117413, SDR43U1[Homo sapiens]

MGC11726, MGC27866[Mus musculus]

Summaries for BLVRB

Entrez Gene summary for BLVRB:

The final step in heme metabolism in mammals is catalyzed by the cytosolic biliverdin reductase enzymes A and B (EC 1.3.1.24).

OMIM - description for BLVRB:

The final step in heme metabolism in mammals is catalyzed by the cytosolic biliverdin reductase enzymes A and B

Wikipedia summary for BLVRB:

Biliverdin reductase (BVR) is an enzyme (EC 1.3.1.24) found in the liver that facilitates the conversion of biliverdin to bilirubin. It accomplishes this through the reduction of a double-bond between the second and third pyrrole ring into a single-bond. There are two isozymes, in humans, each encoded by its own gene, biliverdin reductase A (BLVRA) and biliverdin reductase B (BLVRB).

Human BLVRB Protein General Information

• Protein names: Recommended name: Flavin reductase (NADPH) Short name=FR
• Sequence length: 206 AA.
• Catalytic activity: Reduced riboflavin + NADP+ = riboflavin + NADPH. Bilirubin + NAD(P)+ = biliverdin + NAD(P)H.
• Subunit structure: Monomer.
• Subcellular location: Cytoplasm
• Tissue specificity: Predominantly expressed in liver and erythrocytes. At lower levels in heart, lung, adrenal gland and cerebrum
• Enzyme regulation: Mesobiliverdin acts as competitve inhibitor for flavin reduction, indicating that flavin and tetrapyrrole substrates compete for the same site

General information above from UniProt

Function for BLVRB Protein

UniProtKB:

Broad specificity oxidoreductase that catalyzes the NADPH-dependent reduction of a variety of flavins, such as riboflavin, FAD or FMN, biliverdins, methemoglobin and PQQ (pyrroloquinoline quinone). Contributes to heme catabolism and metabolizes linear tetrapyrroles. Can also reduce the complexed Fe3+ iron to Fe2+ in the presence of FMN and NADPH. In the liver, converts biliverdin to bilirubin.

Genatlas:

• flavin reductase (NADPH), catalyzing electron transfer from reduced pyridine nucleotides to flavins as well as methylene blue, pyrroloquinoline quinone, riboflavin, or methemoglobin
• BLVRB possible role in protecting cells from oxidative damage or in regulating iron metabolism
• In the liver, BLVRB converte biliverdin to bilirubin
• BLVRB displays an alpha/beta dinucleotide binding fold