Sandbox 212: Difference between revisions

From Proteopedia
Jump to navigationJump to search
No edit summary
No edit summary
Line 54: Line 54:
The first system of regulation involves inhibition by malonyl-CoA, an intermediate in the synthesis of fatty acids. Malonyl-CoA inhibits long-chain carnitine acyltransferase activity by all three enzymes at similar concentrations in the physiological range. In addition, the mitochondrial ( CAT) and peroxisomal (COT) enzymes are known to be regulated at the level of mRNA transcription by a number of shared factors. Although the microsomal enzyme is less well studied, there does, indeed, appear to be a pattern of coordinate regulation for this system.
The first system of regulation involves inhibition by malonyl-CoA, an intermediate in the synthesis of fatty acids. Malonyl-CoA inhibits long-chain carnitine acyltransferase activity by all three enzymes at similar concentrations in the physiological range. In addition, the mitochondrial ( CAT) and peroxisomal (COT) enzymes are known to be regulated at the level of mRNA transcription by a number of shared factors. Although the microsomal enzyme is less well studied, there does, indeed, appear to be a pattern of coordinate regulation for this system.
== Carnitine acetyltransferase deficiency and diseases ==
== Carnitine acetyltransferase deficiency and diseases ==
Mutation and dysregulation of CPTs are linked to serious human diseases. Recessive mutations of CPT-I and CPT-II can produce hypoketonemia and hypoglycemia in patients, while CPT-II deficiency is the most common cause of abnormal lipid metabolism in skeletal muscle.Single-point mutations as well as insertions/deletions in the CPT genes can produce the clinical phenotype. The hypoglycemia observed in patients with reduced CPT-I activity suggests that antagonists of CPT-Is may be able to lower blood glucose levels. A covalent CPT-I inhibitor, etomoxir, can lower blood glucose levels in diabetic animals and humans, showing that such inhibitors may be efficacious for the treatment of type 2 diabetes.
Mutation and dysregulation of CPTs are linked to serious human diseases. Recessive mutations of CPT-I and CPT-IICPT-I and CPT-II are crucial for the beta-oxidation of long-chain fatty acids in the mitochondria by enabling their transport across the mitochondrial membrane.  can produce hypoketonemia and hypoglycemia in patients, while CPT-II deficiency is the most common cause of abnormal lipid metabolism in skeletal muscle.Single-point mutations as well as insertions/deletions in the CPT genes can produce the clinical phenotype. The hypoglycemia observed in patients with reduced CPT-I activity suggests that antagonists of CPT-Is may be able to lower blood glucose levels. A covalent CPT-I inhibitor, etomoxir, can lower blood glucose levels in diabetic animals and humans, showing that such inhibitors may be efficacious for the treatment of type 2 diabetes.
== References ==
== References ==