CLPX

The protein encoded by this gene is part of a protease found in mitochondria. This protease is ATP-dependent and targets specific proteins for degradation. The protease consists of two heptameric rings of the CLPP catalytic subunit sandwiched between two hexameric rings of the chaperone subunit encoded by this gene. Targeted proteins are unwound by this protein and then passed on to the CLPP subunit for degradation. Two transcript variants, one protein-coding and the other non-protein coding, have been found for this gene. [provided by RefSeq, Nov 2015]

Full Name

caseinolytic mitochondrial matrix peptidase chaperone subunit

Function

ATP-dependent specificity component of the Clp protease complex. Hydrolyzes ATP (PubMed:28874591).

Targets specific substrates for degradation by the Clp complex (PubMed:11923310, PubMed:22710082).

Can perform chaperone functions in the absence of CLPP. Enhances the DNA-binding activity of TFAM and is required for maintaining a normal mitochondrial nucleoid structure (PubMed:22841477).

ATP-dependent unfoldase that stimulates the incorporation of the pyridoxal phosphate cofactor into 5-aminolevulinate synthase, thereby activating 5-aminolevulinate (ALA) synthesis, the first step in heme biosynthesis (PubMed:28874591).

Important for efficient erythropoiesis through upregulation of heme biosynthesis (PubMed:25957689, PubMed:28874591).

Biological Process

ATP metabolic process Source: UniProtKB
Protein catabolic process Source: GO_Central
Protein folding Source: InterPro
Proteolysis Source: GO_Central
Proteolysis involved in cellular protein catabolic process Source: UniProtKB

Cellular Location

Mitochondrion; Mitochondrion nucleoid

Involvement in disease

Protoporphyria, erythropoietic, 2 (EPP2):
An autosomal dominant form of porphyria with onset in infancy. Porphyrias are inherited defects in the biosynthesis of heme, resulting in the accumulation and increased excretion of porphyrins or porphyrin precursors. They are classified as erythropoietic or hepatic, depending on whether the enzyme deficiency occurs in red blood cells or in the liver. Erythropoietic protoporphyria is marked by excessive protoporphyrin in erythrocytes, plasma, liver and feces, and by widely varying photosensitive skin changes ranging from a burning or pruritic sensation to erythema, edema and wheals.