Article

Non-coding RNA

Non-coding RNAs (ncRNAs) are RNA molecules transcribed from the genome that are not translated into protein but have regulatory or structural roles. Examples include:

microRNAs (miRNAs): regulate mRNA stability and translation.
small interfering RNAs (siRNAs) and piwi‑interacting RNAs (piRNAs): involved in transposon silencing and genome defence.
long non‑coding RNAs (lncRNAs): diverse roles in chromatin regulation and nuclear architecture (for example, XIST in X‑chromosome inactivation).

ncRNAs are important epigenetic regulators because they guide chromatin modifiers, control transcript stability and mediate intercellular signalling in some contexts.