IUBMB Enzyme Nomenclature


Accepted name: ribonuclease III

Reaction: Endonucleolytic cleavage to a 5'-phosphomonoester

Other name(s): RNase III; ribonuclease 3

Comments: This is an endoribonuclease that cleaves double-stranded RNA molecules [4]. The cleavage can be either a single-stranded nick or double-stranded break in the RNA, depending in part upon the degree of base-pairing in the region of the cleavage site [5]. Specificity is conferred by negative determinants, i.e., the presence of certain Watson-Crick base-pairs at specific positions that strongly inhibit cleavage [6]. RNase III is involved in both rRNA processing and mRNA processing and decay.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9073-62-5


1. Crouch, R.J. Ribonuclease 3 does not degrade deoxyribonucleic acid-ribonucleic acid hybrids. J. Biol. Chem. 249 (1974) 1314-1316. [PMID: 4592261]

2. Rech, J., Cathala, G. and Jeanteur, P. Isolation and characterization of a ribonuclease activity specific for double-stranded RNA (RNase D) from Krebs II ascites cells. J. Biol. Chem. 255 (1980) 6700-6706. [PMID: 6248530]

3. Robertson, H.D., Webster, R.E. and Zinder, N.D. Purification and properties of ribonuclease III from Escherichia coli. J. Biol. Chem. 243 (1968) 82-91. [PMID: 4865702]

4. Grunberg-Manago, M. Messenger RNA stability and its role in control of gene expression in bacteria and phages. Annu. Rev. Genet. 33 (1999) 193-227. [PMID: 10690408]

5. Court, D. RNA processing and degradation by RNase III in control of mRNA stability. In: Belasco, J.G. and Brawerman, G. (Ed.), Control of Messenger RNA Stability, vol. , Academic Press, New York, 1993, pp. 71-116.

6. Zhang, K. and Nicholson, A.W. Regulation of ribonuclease III processing by double-helical sequence antideterminants. Proc. Natl. Acad. Sci. USA 94 (1997) 13437-13441. [PMID: 9391043]

[EC created 1978, modified 2006]

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