Final answer:
An ncRNA functions as a decoy by physically blocking a cellular process, often by binding to proteins or other RNA molecules. This interaction can regulate gene expression by altering the stability and degradation of mRNA, which affects protein synthesis.
Step-by-step explanation:
When an ncRNA functions as a decoy, it may physically prevent or block a cellular process from happening. Non-coding RNA molecules, including antisense RNA, miRNAs, and siRNAs, play a major role in RNA interference (RNAi), which is a natural regulatory mechanism where mRNA molecules are prevented from guiding protein synthesis. NC-RNAs can bind to proteins or other RNAs, thereby blocking their interaction with their intended targets, or leading to the degradation or stabilization of RNA molecules, ultimately controlling the expression of genes.
RNA stability is influenced by RNA-binding proteins (RBPs), which bind to the untranslated regions (UTRs) of RNA. This interaction can either increase or decrease the stability of the RNA, affecting how long the RNA remains intact in the cytoplasm and thus influencing protein synthesis. By binding to these proteins and RNAs, ncRNAs can modulate the stability of certain mRNA molecules, acting as a decoy that alters the normal function of cellular processes.