Riboregulator refers to a class of RNA molecules that act as regulators for gene expression. These molecules can be called different names depending on their specific functions. For instance, small non-coding RNAs that interact with mRNA to repress translation are known as microRNAs. Similarly, small RNAs that catalyze RNA cleavage to regulate gene expression are called small interfering RNAs. Riboswitches are another type of riboregulator that control gene expression by binding to small molecules or other metabolites. Finally, ribozymes are catalytic RNA molecules that regulate gene expression by cleaving or modifying RNA molecules. These different types of riboregulators play an important role in cellular functions and their diverse mechanisms contribute to the complexity of gene regulation.