Amyloid Beta Displaces Tau in Neurons, Study Finds
Get the Health newsletter
Daily health & science — research, biotech, public health, the studies worth knowing. Free.
- UC Riverside researchers published a study in PNAS Nexus proposing that amyloid beta (a-beta) displaces tau from microtubules inside neurons, disrupting the cell's internal transport network and potentially triggering Alzheimer's.
- Lead author Ryan Julian, a UCR chemistry professor, said a-beta and tau bind to microtubules with similar strength, meaning a-beta accumulation can push tau out of its normal position.
- Scientists attached fluorescent markers to a-beta and confirmed it binds directly to microtubules — the tube-like structures that carry essential materials inside neurons.
- The model could explain why thousands of clinical trials targeting a-beta plaques have failed to stop or reverse the disease: the critical damage may begin inside neurons, not from external plaque buildup.
- The proposed mechanism aligns with age-related decline in autophagy, the brain's natural protein-recycling process, which could allow a-beta to accumulate inside neurons over time.
- The researchers noted their theory fits with observations that lithium may reduce Alzheimer's risk, since lithium also helps stabilize microtubules — raising the possibility of microtubule-protecting treatments.
Why it matters: This reframes Alzheimer's as a microtubule-binding competition rather than a plaque disease, suggesting decades of amyloid-clearing drugs may have targeted the wrong stage of the disease. Future treatments could shift toward protecting microtubules or boosting the brain's protein-recycling autophagy process instead of dissolving clumps.
