Final answer:
Non-coding RNAs (ncRNAs) such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) have vital cis functions that include regulating gene expression within close proximity to where they are transcribed. Small ncRNAs like microRNAs (miRNAs) and small interfering RNAs (siRNAs) also play critical roles in post-transcriptional regulation, impacting various cellular processes and disease development.
Step-by-step explanation:
Non-Coding RNAs with Cis Function
Non-coding RNAs (ncRNAs) that have a cis function often play a crucial role in regulating gene expression within the same molecule of DNA from which they are transcribed. For example, long non-coding RNAs (lncRNAs) may arise from various regions of the genome, such as antisense, intronic, or intergenic areas, and can influence the activity of nearby genes. Another form of ncRNAs, circular RNAs (circRNAs), are known to have stable levels that vary during certain developmental processes like neural development or synapse formation in mice, indicating their functional role as regulators of gene expression, potentially affecting the genes from which they originated.
MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) are other examples of ncRNAs with regulatory functions. These small RNAs can bind to the RNA-Induced Silencing Complex (RISC) and target specific mRNAs for degradation or repression, controlling gene expression post-transcriptionally. Interestingly, the dysregulation of these ncRNAs has been linked to various human diseases, including cancer, highlighting their significance beyond basic cellular functions.
ncRNAs, gene expression, and RNA regulation are essential in understanding how cells control the flow of genetic information and maintain homeostasis. The diverse functions of ncRNAs, particularly those with a cis regulatory role, underscore their importance in cellular processes and disease pathogenesis.