CYB5R3
Function
Catalyzes the reduction of two molecules of cytochrome b5 using NADH as the electron donor.
Involvement in disease
Methemoglobinemia CYB5R3-related
METHB-CYB5R3
A form of methemoglobinemia, a hematologic disease characterized by the presence of excessive amounts of methemoglobin in blood cells, resulting in decreased oxygen carrying capacity of the blood, cyanosis and hypoxia. There are two types of methemoglobinemia CYB5R3-related. In type 1, the defect affects the soluble form of the enzyme, is restricted to red blood cells, and causes well-tolerated methemoglobinemia. In type 2, the defect affects both the soluble and microsomal forms of the enzyme and is thus generalized, affecting red cells, leukocytes and all body tissues. Type 2 methemoglobinemia is associated with mental deficiency and other neurologic symptoms.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the flavoprotein pyridine nucleotide cytochrome reductase family.
Tissue Specificity
Isoform 2
Expressed at late stages of erythroid maturation.
Cellular localization
- Isoform 1
- Endoplasmic reticulum membrane
- Lipid-anchor
- Cytoplasmic side
- Mitochondrion outer membrane
- Lipid-anchor
- Cytoplasmic side
- Isoform 2
- Cytoplasm
Alternative names
DIA1, CYB5R3, NADH-cytochrome b5 reductase 3, B5R, Cytochrome b5 reductase, Diaphorase-1