COG8 (Conserved Oligomeric Golgi Complex 8) is the final subunit of the COG complex, completing the hetero-octameric assembly essential for Golgi apparatus function. As part of lobe B, COG8 collaborates with COG5-7 to coordinate vesicular trafficking and maintain proper protein glycosylation within the secretory pathway.
| Symbol | COG8 |
|---|---|
| Full Name | Conserved Oligomeric Golgi Complex 8 |
| Chromosomal Location | Chr16q22.1 |
| NCBI Gene ID | 84342 |
| UniProt ID | Q9Y5J2 |
| Associated Diseases | CDG IIh |
COG8 (approximately 611 amino acids) represents the C-terminal component of lobe B in the COG complex. It contains multiple coiled-coil domains that mediate interactions with other COG subunits, particularly COG5 and COG7. COG8 contributes to complex stability and participates in the tethering functions essential for retrograde Golgi trafficking [1][2]. [1]
The COG complex functions as a multisubunit tethering complex (MTC) that:
Golgi fragmentation represents an early event in AD pathogenesis, preceding neurofibrillary tangle formation. COG8 maintains Golgi integrity essential for proper trafficking of amyloid precursor protein (APP) and secretase enzymes involved in amyloid-beta generation [5][6].
The COG complex supports endolysosomal trafficking pathways critical for clearing alpha-synuclein aggregates. COG8 dysfunction may impair autophagic flux, contributing to protein aggregate accumulation in vulnerable neurons [7].
COG8 deficiency triggers Golgi stress responses, including upregulation of Golgi matrix proteins and activation of unfolded protein response pathways. These responses are relevant to neurodegenerative disease mechanisms [8].
COG8 mutations cause CDG IIh (OMIM #611102), characterized by:
The phenotype reflects the essential role of COG8 in protein glycosylation and neuronal development [9][10].
COG8 deficiency results in:
COG8 interacts with:
Current research areas include:
Sutton et al. Therapeutic Golgi (2023). 2023. ↩︎