MPC1 | |||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
Aliases | MPC1 , BRP44L, MPYCD, dJ68L15.3, CGI-129, mitochondrial pyruvate carrier 1, SLC54A1 | ||||||||||||||||||||||||||||||||||||||||||||||||||
External IDs | OMIM: 614738; MGI: 1915240; HomoloGene: 9384; GeneCards: MPC1; OMA:MPC1 - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
|
Mitochondrial pyruvate carrier 1 (MPC1), also known as brain protein 44-like (BRP44L) and SLC54A1, is a protein that in humans is encoded by the MPC1 gene. [5] It is part of the Mitochondrial Pyruvate Carrier (MPC) protein family. This protein is involved in transport of pyruvate across the inner membrane of mitochondria in preparation for the pyruvate dehydrogenase reaction.
Click on genes, proteins and metabolites below to link to respective articles. [§ 1]
Mitochondrial pyruvate carrier deficiency (MPYCD) is an autosomal recessive disease due to mutations in the MPC1 gene on chromosome 6q27. It is an inborn error of carbohydrate metabolism that blocks aerobic glycolysis by preventing the transport of pyruvate from the cytosol into the mitochondrion for oxidative phosphorylation; however, anaerobic glycolysis is preserved. Common signs and symptoms include poor growth, normal lactate/pyruvate ratio (however both lactate and pyruvate are in higher than normal concentrations), hepatomegaly, lactic acidosis, hypoglycemia, neurological problems, and hypotonia. [6] A disease with comparable symptoms is also seen in autosomal recessive mutations of the MPC2 gene. [7]
Glycolysis is the metabolic pathway that converts glucose into pyruvate and, in most organisms, occurs in the liquid part of cells. The free energy released in this process is used to form the high-energy molecules adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide (NADH). Glycolysis is a sequence of ten reactions catalyzed by enzymes.
Gluconeogenesis (GNG) is a metabolic pathway that results in the biosynthesis of glucose from certain non-carbohydrate carbon substrates. It is a ubiquitous process, present in plants, animals, fungi, bacteria, and other microorganisms. In vertebrates, gluconeogenesis occurs mainly in the liver and, to a lesser extent, in the cortex of the kidneys. It is one of two primary mechanisms – the other being degradation of glycogen (glycogenolysis) – used by humans and many other animals to maintain blood sugar levels, avoiding low levels (hypoglycemia). In ruminants, because dietary carbohydrates tend to be metabolized by rumen organisms, gluconeogenesis occurs regardless of fasting, low-carbohydrate diets, exercise, etc. In many other animals, the process occurs during periods of fasting, starvation, low-carbohydrate diets, or intense exercise.
Pyruvate carboxylase (PC) encoded by the gene PC is an enzyme of the ligase class that catalyzes the physiologically irreversible carboxylation of pyruvate to form oxaloacetate (OAA).
Pyruvate dehydrogenase deficiency is a rare neurodegenerative disorder associated with abnormal mitochondrial metabolism. PDCD is a genetic disease resulting from mutations in one of the components of the pyruvate dehydrogenase complex (PDC). The PDC is a multi-enzyme complex that plays a vital role as a key regulatory step in the central pathways of energy metabolism in the mitochondria. The disorder shows heterogeneous characteristics in both clinical presentation and biochemical abnormality.
Glycine encephalopathy is a rare autosomal recessive disorder of glycine metabolism. After phenylketonuria, glycine encephalopathy is the second most common disorder of amino acid metabolism. The disease is caused by defects in the glycine cleavage system, an enzyme responsible for glycine catabolism. There are several forms of the disease, with varying severity of symptoms and time of onset. The symptoms are exclusively neurological in nature, and clinically this disorder is characterized by abnormally high levels of the amino acid glycine in bodily fluids and tissues, especially the cerebrospinal fluid.
Aldolase B also known as fructose-bisphosphate aldolase B or liver-type aldolase is one of three isoenzymes of the class I fructose 1,6-bisphosphate aldolase enzyme, and plays a key role in both glycolysis and gluconeogenesis. The generic fructose 1,6-bisphosphate aldolase enzyme catalyzes the reversible cleavage of fructose 1,6-bisphosphate (FBP) into glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (DHAP) as well as the reversible cleavage of fructose 1-phosphate (F1P) into glyceraldehyde and dihydroxyacetone phosphate. In mammals, aldolase B is preferentially expressed in the liver, while aldolase A is expressed in muscle and erythrocytes and aldolase C is expressed in the brain. Slight differences in isozyme structure result in different activities for the two substrate molecules: FBP and fructose 1-phosphate. Aldolase B exhibits no preference and thus catalyzes both reactions, while aldolases A and C prefer FBP.
E3 binding protein also known as pyruvate dehydrogenase protein X component, mitochondrial is a protein that in humans is encoded by the PDHX gene. The E3 binding protein is a component of the pyruvate dehydrogenase complex found only in eukaryotes. Defects in this gene are a cause of pyruvate dehydrogenase deficiency which results in neurological dysfunction and lactic acidosis in infancy and early childhood. This protein is also a minor antigen for antimitochondrial antibodies. These autoantibodies are present in nearly 95% of patients with primary biliary cholangitis, an autoimmune disease of the liver. In primary biliary cholangitis, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. Primary biliary cholangitis eventually leads to liver failure.
GLUT5 is a fructose transporter expressed on the apical border of enterocytes in the small intestine. GLUT5 allows for fructose to be transported from the intestinal lumen into the enterocyte by facilitated diffusion due to fructose's high concentration in the intestinal lumen. GLUT5 is also expressed in skeletal muscle, testis, kidney, fat tissue (adipocytes), and brain.
Pyruvate dehydrogenase E1 component subunit alpha, somatic form, mitochondrial is an enzyme that in humans is encoded by the PDHA1 gene.The pyruvate dehydrogenase complex is a nuclear-encoded mitochondrial matrix multienzyme complex that provides the primary link between glycolysis and the tricarboxylic acid (TCA) cycle by catalyzing the irreversible conversion of pyruvate into acetyl-CoA. The PDH complex is composed of multiple copies of 3 enzymes: E1 (PDHA1); dihydrolipoyl transacetylase (DLAT) ; and dihydrolipoyl dehydrogenase (DLD). The E1 enzyme is a heterotetramer of 2 alpha and 2 beta subunits. The E1-alpha subunit contains the E1 active site and plays a key role in the function of the PDH complex.
Lactate dehydrogenase A (LDHA) is an enzyme which in humans is encoded by the LDHA gene. It is a monomer of Lactate dehydrogenase, which exists as a tetramer. The other main subunit is lactate dehydrogenase B (LDHB).
Lactate dehydrogenase (LDH or LD) is an enzyme found in nearly all living cells. LDH catalyzes the conversion of pyruvate to lactate and back, as it converts NAD+ to NADH and back. A dehydrogenase is an enzyme that transfers a hydride from one molecule to another.
Enolase 3 (ENO3), more commonly known as beta-enolase (ENO-β), is an enzyme that in humans is encoded by the ENO3 gene.
Mitochondrial pyruvate carrier 2 (MPC2) also known as brain protein 44 (BRP44) is a protein that in humans is encoded by the MPC2 gene. It is a member of the Mitochondrial Pyruvate Carrier (MPC) protein family. This protein is involved in transport of pyruvate across the inner membrane of mitochondria in preparation for the pyruvate dehydrogenase reaction.
Forkhead box protein K1 is a transcription factor of the forkhead box family that in humans is encoded by the FOXK1 gene.
Iron-sulfur cluster assembly enzyme ISCU, mitochondrial is a protein that in humans is encoded by the ISCU gene. It encodes an iron-sulfur (Fe-S) cluster scaffold protein involved in [2Fe-2S] and [4Fe-4S] cluster synthesis and maturation. A deficiency of ISCU is associated with a mitochondrial myopathy with lifelong exercise intolerance where only minor exertion causes tachycardia, shortness of breath, muscle weakness and myalgia.
Methylmalonate-semialdehyde dehydrogenase [acylating], mitochondrial (MMSDH) is an enzyme that in humans is encoded by the ALDH6A1 gene.
Inborn errors of carbohydrate metabolism are inborn error of metabolism that affect the catabolism and anabolism of carbohydrates.
Pyruvate dehydrogenase (lipoamide) beta, also known as pyruvate dehydrogenase E1 component subunit beta, mitochondrial or PDHE1-B is an enzyme that in humans is encoded by the PDHB gene. The pyruvate dehydrogenase (PDH) complex is a nuclear-encoded mitochondrial multienzyme complex that catalyzes the overall conversion of pyruvate to acetyl-CoA and CO2, and provides the primary link between glycolysis and the tricarboxylic acid (TCA) cycle. The PDH complex is composed of multiple copies of three enzymatic components: pyruvate dehydrogenase (E1), dihydrolipoamide acetyltransferase (E2) and lipoamide dehydrogenase (E3). The E1 enzyme is a heterotetramer of two alpha and two beta subunits. This gene encodes the E1 beta subunit. Mutations in this gene are associated with pyruvate dehydrogenase E1-beta deficiency.
Dehydrogenase E1 and transketolase domain containing 1 is a protein that in humans is encoded by the DHTKD1 gene. This gene encodes a component of a mitochondrial 2-oxoglutarate-dehydrogenase-complex-like protein involved in the degradation pathways of several amino acids, including lysine. Mutations in this gene are associated with 2-aminoadipic 2-oxoadipic aciduria and Charcot-Marie-Tooth Disease Type 2Q.
The citrate-malate shuttle is a series of chemical reactions, commonly referred to as a biochemical cycle or system, that transports acetyl-CoA in the mitochondrial matrix across the inner and outer mitochondrial membranes for fatty acid synthesis. Mitochondria are enclosed in a double membrane. As the inner mitochondrial membrane is impermeable to acetyl-CoA, the shuttle system is essential to fatty acid synthesis in the cytosol. It plays an important role in the generation of lipids in the liver.