Small non-coding RNAs are typically only ~18–40 nucleotides in length; however their effect on cellular processes is profound. Small RNA has been shown to play critical roles in developmental timing, cell fate, tumor progression, and neurogenesis. Animals, plants, and fungi contain several distinct classes of small RNA, including:
- microRNA (miRNA)
- short interfering RNA (siRNA)
- piwi-interacting RNA (piRNA)
- siRNA RNA (rasiRNA)
