Members of this family are involved in rDNA transcription and rRNA processing. They probably also cleave a stem-loop structure at the 3' end of U2 snRNA to ensure formation of the correct U2 3' end; they are involved in polyadenylation-independent transcription termination. Some members may be mitochondrial ribosomal protein subunit L15, others may be 60S ribosomal protein L3.
This domain is found in eukaryotic, bacterial and archeal ribonuclease III (RNAse III) proteins. RNAse III is a double stranded RNA-specific endonuclease [PUBMED:11738048, PUBMED:15016361]. Prokaryotic RNAse III is important in post-transcriptional control of mRNA stability and translational efficiency. It is involved in the processing of ribosomal RNA precursors. Prokaryotic RNAse III also plays a role in the maturation of tRNA precursors and in the processing of phage and plasmid transcripts. Eukaryotic RNase III's participate (through direct cleavage) in rRNA processing, in processing of small nucleolar RNAs (snoRNAs) and snRNA's (components of the spliceosome). In eukaryotes RNase III or RNaseIII like enzymes such as Dicer are involved in RNAi (RNA interference) and miRNA (micro-RNA) gene silencing [PUBMED:14983173, PUBMED:15066275, PUBMED:11809414].