COPS9

Chr 2

COP9 signalosome subunit 9

Also known as: CSNAP, MYEOV2

NCBI Gene: 150678 ENSG00000172428 UniProt: Q8WXC6 OMIM: 619349

The COPS9 protein is a component of the COP9 signalosome complex that regulates protein degradation pathways by controlling the activity of cullin-RING E3 ubiquitin ligase complexes through deneddylation. Pathogenic variants in COPS9 cause autosomal recessive developmental and epileptic encephalopathy with microcephaly, characterized by early-onset seizures, severe developmental delay, and progressive microcephaly. This gene shows tolerance to loss-of-function variation (pLI 0.001), suggesting the disease mechanism may involve specific damaging variants rather than simple protein loss.

OMIM ResearchSummary from RefSeq, UniProt

Involved in several processes, including cellular response to UV; negative regulation of protein localization to nucleolus; and negative regulation of protein neddylation. Located in chromatin; cytoplasm; and nucleus. [provided by Alliance of Genome Resources, Jun 2026]

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

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P/LP missense

1.48

LOEUF

Multiple*

Mechanism· predicted