Transfer of memory via RNA injection in Aplysia—trained donor RNA enhanced the siphon-withdrawal reflex in untrained recipients—offers the strongest challenge to date to the synaptic plasticity hypothesis¶

Claim · All claims
Evidence · 1 study · review r3 · q2
Currency · newest study 2019 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? Untrained Aplysia injected with RNA from sensitization-trained donors showed significant enhancement of the siphon-withdrawal reflex, an effect blocked by a DNMT inhibitor; sensory neurons incubated in trained donor RNA showed enhanced excitability, with no effect on motor neurons. → Wickliffe C. Abraham 2019

Evidence¶

Wickliffe C. Abraham 2019¶

Wickliffe C. Abraham, Owen D. Jones and David L. Glanzman. (2019). Is plasticity of synapses the mechanism of long-term memory storage? npj Science of Learning 4:9. https://doi.org/10.1038/s41539-019-0048-y

q2 · i? · review · r3

Narrative review attributing this experiment to Bédécarrats et al. Tail-shock-trained donors' RNA was injected into untrained recipients; recipients of trained donor RNA showed significant SWR enhancement while untrained donor RNA recipients did not. The effect depended on DNA methylation, blocked by RG108.

"When tested 24 h post-injection, the animals that received the trained donor RNA exhibited significant enhancement of the SWR, whereas the recipients of the untrained donor RNA did not"

Discussion¶

Related Claims¶

• DNMT inhibitors block memory formation and/or consolidation and disrupt well-consolidated memory, implicating DNA methylation in memory processes — related
• Memories can persist and be reinstated in the absence of learning-induced synaptic alterations, supporting cell-intrinsic storage — related
• Retrograde intervention experiments—reversing LTP or depotentiating learning-strengthened synapses—cause memory loss, lending strong support to the synaptic plasticity and memory hypothesis — reports the opposite
• Non-coding RNAs participate in learning and memory: microRNAs in fear-related learning and memory, and long non-coding RNAs regulated by experience in behavioural adaptation, as the review reports — related