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PROSITE documentation PDOC00448

Ribonuclease III family signature and profile


Prokaryotic ribonuclease III (EC (gene rnc) [1] is an enzyme that digests double-stranded RNA. It is involved in the processing of ribosomal RNA precursors and of some mRNAs. RNase III is evolutionary related [2] to the following proteins:

  • Fission yeast pac1, a ribonuclease that probably inhibits mating and meiosis by degrading a specific mRNA required for sexual development.
  • Yeast ribonuclease III (gene RNT1), a dsRNA-specific nuclease that cleaves eukaryotic preribosomal RNA at various sites.
  • Caenorhabditis elegans hypothetical protein F26E4.13.
  • Paramecium bursaria chlorella virus 1 protein A464R.
  • Synechocystis strain PCC 6803 hypothetical protein slr0346.
  • Fission yeast hypothetical protein SpAC8A4.08c, a protein with a N-terminal helicase domain and a C-terminal RNase III domain.
  • Caenorhabditis elegans hypothetical protein K12H4.8, a protein with the same structure as SpAC8A4.08c.

These proteins share regions of sequence similarity; one of which is a highly conserved stretch of 9 residues which we use as a signature pattern.

Last update:

December 2004 / Pattern and text revised.

Technical section

PROSITE methods (with tools and information) covered by this documentation:

RNASE_3_2, PS50142; Ribonuclease III family domain profile  (MATRIX)

RNASE_3_1, PS00517; Ribonuclease III family signature  (PATTERN)


1AuthorsNashimoto H., Uchida H.
TitleDNA sequencing of the Escherichia coli ribonuclease III gene and its mutations.
SourceMol. Gen. Genet. 201:25-29(1985).
PubMed ID3903434

2AuthorsMian I.S.
TitleComparative sequence analysis of ribonucleases HII, III, II PH and D.
SourceNucleic Acids Res. 25:3187-3195(1997).
PubMed ID9241229

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