HOMER1/A0104

HOMER1 (homer homolog 1 (Drosophila)), also known as A0104, is an immediate-early gene that binds to the intracellular C-terminus of metabotropic glutamate receptors at excitatory synapses.

HOMER1 (homer homolog 1 (Drosophila)), also known as A0104, is an immediate-early gene that binds to the intracellular C-terminus of metabotropic glutamate receptors at excitatory synapses. The binding of HOMER1 to metabotropic glutamate receptors via proline-rich motifs directly regulates their activity. HOMER1 acts as a biochemical link between metabotropic glutamate receptors and inositol trisphosphate receptors. HOMER1 is widely expressed in the brain, particularly in the cortex and olfactory bulb. Sleep deprivation is noted to significantly alter HOMER1 expression in the brain. HOMER1 is selectively up-regulated in the spinal cord following N-methyl-D-aspartate (NMDA) receptor-dependent peripheral inflammation. As well as learning deficits, HOMER1 knock-out mice show enhanced conditioned reward and locomotory behavior following cocaine administration. HOMER1 knock-outs show a 50% decrease in extracellular gluatamate in the nucleus accumbens. This phenotype expression decrease can be rescued by cocaine injection.