LRRC37A

Leucine rich repeat containing 37A is a protein in humans that is encoded by the LRRC37A gene.

The LRRC37 gene family has been expanded in the genome of the simians through segmental duplications leading to new genes in simian, hominid and human species. Most of these new genes belong to the ancestral LRRC37A-type. The human genomes contains at least 4 encoding gene paralogs with 3 of the ancestral type: LRRC37A, LRRC37A2, LRRC37A3 and a new type of receptor shared between hominid species: LRRC37B.

In the human cerebral cortex, LRRC37B is selectively expressed in pyramidal neurons at the level of the axon initial segment, which is not found in other nonhuman primate species (chimpanzees, macaques). It decreases there the excitability of the neurons, a feature specific to the human species compared to other mammalian species. It acts by binding to secreted FGF13A and SCN1B which leads to an inhibition of the voltage-gate sodium channels which generate the action potentials.