Do you remember the name of your fourth-grade teacher? How about what you had for lunch last Thursday? Highschool Prom date? Yeah, we went stag too, but if you’re having a hard time remebering key events, ncRNAs may be to blame! The human brain expresses high numbers of ncRNAs, and mounting evidence indicates important contributions of ncRNAs to memory formation and maintenance.
In a recent review in The Neuroscientist, John Mattick and colleagues at the University of Queensland, the Université Pierre et Marie Curie−Paris, the University of California at Santa Barbara, and the Albert Einstein College of Medicine describe various roles of ncRNAs in the molecular mechanisms that underlie long-term memory.
Memories are thought to arise from changes in the strength or plasticity of synapses, the junctions between neurons across which nerve impulses are transmitted. In response to synaptic activity, miRNAs and siRNAs can affect the stability and translation of specific mRNA transcripts, which enables rapid changes in protein synthesis. NcRNAs can regulate memory-associated gene transcription by directing chromatin modification and DNA methylation. Some evidence suggests that ncRNAs also serve as signaling molecules by trafficking across synapses, similar to neurotransmitters. These results suggest a pivotal role for ncRNAs in memory formation. For more thought-provoking details, see Neuroscientist, November 2008.