GCOM1 combined protein 1 (GCOM1)

GCOM1 combined protein 1 (GCOM1) is a unique, complex gene product resulting from *readthrough transcription across the MYZAP and POLR2M genes* on chromosome 15, generating a protein with domains from both parent loci as well as unique exons[1][3][2]. GCOM1 proteins are expressed predominantly in the **central nervous system** and at the **intercalated disks of cardiomyocytes**, where they participate in **transcription elongation** (by interacting with the RNA polymerase II complex), **cell–cell adhesion** in the heart, and possibly the modulation of NMDA receptor (NMDAR) function in the brain[1][3]. GCOM1 variants that result in loss of function have been directly implicated in **familial dilated and hypertrophic cardiomyopathy**[3]. Experimental evidence suggests a possible role in **neuroprotection** by modulating NMDA receptor–mediated calcium influx, but the exact CNS function is still not fully characterized[1]. No drugs are currently known to target GCOM1 directly, and its major therapeutic potential is as a modulator within protein complexes—especially those relevant to heart and brain pathology. Key evidence: - GCOM1 is the gene product of a complex transcription unit encompassing exons from MYZAP and POLR2M, producing unique proteins not found in either parent gene alone[2][3]. - GCOM1 interacts with cardiac and neuronal proteins, including the NR1 subunit of the NMDA receptor, and is implicated in both cardiac structural integrity and possible neuroprotective pathways[1]. - Homozygous GCOM1 truncating mutations cause familial cardiomyopathy; there are suggested implications for neuropsychiatric and neurodegenerative diseases, but direct clinical links are not fully established[3][1]. No pharmacologic agents are currently known to act on GCOM1 or its protein products[1][3]. Pathogenic GCOM1 variants serve as potential genetic biomarkers in hereditary cardiomyopathy assessment[3].

Other names

FLJ30973GRINL1AMYZAP-POLR2MMYZAP-POLR2M readthroughGcom2MYZAPGRINL1A combined proteinDNA-directed RNA polymerase II subunit GRINL1ADNA-directed RNA polymerase II subunit MGRINL1A combined protein Gcom12GRINL1A complex locus 1Glutamate receptor-like protein 1ANMDAR1 subunit-interacting proteinglutamate receptor, ionotropic, N-methyl D-aspartate-like 1A combined proteinmyocardial zonula adherens protein

none known (neither direct pharmacologic agents nor established inhibitors/agonists are documented)