Ras-related protein Rab-6A

RAB6A encodes Rab-6, a small GTPase that functions as a key regulator of intracellular membrane trafficking (UniProt: P20340). The protein cycles between inactive GDP-bound and active GTP-bound states to recruit effector proteins responsible for vesicle formation, movement, tethering, and fusion. RAB6A specifically regulates COPI-independent retrograde transport from the Golgi apparatus back to the endoplasmic reticulum and has been implicated in neuron projection development.

RAB6A is broadly expressed and functions in fundamental membrane trafficking pathways essential for cellular homeostasis. UniProt records no primary disease association; however, the protein's role in vesicle dynamics and neuronal development suggests relevance to neurobiological processes.

In Alzheimer's disease, RAB6A is upregulated in post-mortem AD brain tissue compared to age-matched controls (Chaparral AD proteomics, mean log2FC = +0.2004). This elevation was detected via TMT-labeled proteomics across subcellular fractions from human AD brain, suggesting potential dysregulation of retrograde trafficking or vesicular transport in the disease state, though the functional significance remains to be elucidated.