Summary

Geranylgeranyl transferase type-2 subunit alpha (RABGGTA) is a lipid-modifying enzyme that catalyzes the transfer of geranylgeranyl moieties from geranylgeranyl diphosphate to Rab GTPases, including RAB1A, RAB3A, RAB5A, and RAB7A (UniProt: Q92696). This post-translational modification is essential for membrane localization and function of small GTPases involved in vesicular trafficking and intracellular transport.

RABGGTA functions in lipid metabolism and protein trafficking pathways. No primary disease associations are documented in UniProt for this protein, though Rab proteins themselves are implicated in neuronal membrane dynamics and synaptic function.

In Alzheimer's disease brain proteomics, RABGGTA shows ambiguous regulation across subcellular fractions (mean log2FC = 0.32) when comparing post-mortem AD tissue to age-matched controls (Chaparral AD proteomics). The modest fold-change and variable direction across three measured fractions suggest modest or compartment-specific changes in AD pathology that warrant further investigation of Rab prenylation in neurodegenerative contexts.