Fig. 5.

—Effects of microsatellites at the level of RNA. Long noncoding RNAs (lncRNAs) predominantly consisting of microsatellites have been observed to function in the nuclear matrix and to aggregate into nuclear foci with indications of functional significance. They have also been shown to associate with DNA microsatellites in UTRs. Microsatellite-dominated microRNAs have been observed, but their function is not yet clear. Intronic microsatellites can modulate splicing efficiency, including exon skipping and splice site selection, and UTR repeats can influence the locations of the sites of transcription initiation and termination. Transcribed microsatellites can also affect mRNA half-life, which may be due to formation of secondary structures such as hairpins.