Charged multivesicular body protein 2b

Charged multivesicular body protein 2b (CHMP2B) is a core component of the ESCRT-III complex involved in multivesicular body formation and endosomal cargo sorting (UniProt: Q9UQN3). It functions in delivering intraluminal vesicles to lysosomes for degradation of membrane proteins and participates in membrane fission events including cytokinesis and enveloped virus budding, often in conjunction with the AAA ATPase VPS4.

CHMP2B is associated with frontotemporal dementia and/or amyotrophic lateral sclerosis 7 (FTDALS7), an autosomal dominant neurodegenerative disorder characterized by progressive frontal and temporal lobe atrophy or motor neuron death, with high intrafamilial phenotypic variation (UniProt: Q9UQN3).

In Alzheimer's disease, CHMP2B is significantly upregulated in post-mortem AD brain tissue compared to age-matched controls (Chaparral AD proteomics). The protein shows a mean log2 fold-change of 0.65, consistent with elevated expression across the measured subcellular fractions in TMT-labeled proteomics analysis.