SLC25A22
Solute carrier family 25 member 22 is a protein that in humans is encoded by the "SLC25A22" gene. This gene encodes a mitochondrial glutamate carrier. Mutations in this gene are associated with early infantile epileptic encephalopathy. Expression of this gene is increased in colorectal tumor cells. Structure. The "SLC25A22" gene is located on the p arm of chromosome 11 in position 15.5 and has 9 exons spanning 7,807 base pairs. The gene produces a 34.5 kDa protein composed of 323 amino acids. The encoded protein is a multi-pass transmembrane protein located in the mitochondrial inner membrane. Function. The  protein encoded by "SLC25A22" is involved in the transport of glutamate, cotransported with H+, across the inner mitochondrial membrane. Both "SLC25A22" and "SLC25A18" are mitochondrial glutamate/H+ symporters. Clinical significance. Epileptic encephalopathy. Mutations in the "SLC25A22" gene cause early infantile epileptic encephalopathy 3 (EIEE3), a severe form of epilepsy characterized by frequent tonic seizures or spasms beginning in infancy with a specific EEG finding of suppression-burst patterns, characterized by high-voltage bursts alternating with almost flat suppression phases. Epileptic encephalopathy early infantile type 3 is characterized by a very early onset, erratic and fragmentary myoclonus, massive myoclonus, partial motor  seizures and late tonic spasms. The prognosis is poor, with no effective treatment, and children with the condition either die within 1 to 2 years after birth or survive in a persistent vegetative state. Migrating partial seizures in infancy, caused by a specific G110R mutation in the "SLC25A22" gene, can be inherited. Although expression of "SLC25A22" is high in most tissues, expression is particularly strong in the developing brain, with regions of the brain involved in the genesis and control of myoclonic seizures specifically expressing "SLC25A22" during human development. Colorectal cancer. "SLC25A22" expression is increased in colorectal tumor tissues compared  to matched nontumor colon tissues. Increased expression of the encoded protein was associated with decreased survival times in colorectal cancer patients. Knockdown of this gene in mutant colorectal cells decreased their migration, proliferation, and invasion. Interactions. The encoded protein interacts with SLC38A1, NDUFAF4, and 43 other proteins.