RNA pol III fidelity-determined by selectivity and proofreading activity

Range 10^3 times the error rate determined solely by selectivity correct/incorrect nucleotide
Organism Budding yeast Saccharomyces cerevisiae
Reference Alic N, Ayoub N, Landrieux E, Favry E, Baudouin-Cornu P, Riva M, Carles C. Selectivity and proofreading both contribute significantly to the fidelity of RNA polymerase III transcription. Proc Natl Acad Sci U S A. 2007 Jun 19 104(25):10400-5 AbstractPubMed ID17553959
Method Selectivity was measured as ratio between incorporation of correct to incorrect nucleotide to tRNA gene, 1.8×10^-4 (BNID 105213). Fidelity is the product of selectivity and proofreading. See figure 5 and equation 3. Pol III?, an Incomplete form of Pol III lacking RNA-cleavage activity, can quantitatively incorporate an incorrect nucleotide.
Comments "Determination of relative rates of the reactions producing correct and erroneous transcripts at a specific position on a tRNA gene, combined with computational methods, demonstrated that Pol III has a highly efficient proofreading activity increasing its transcriptional fidelity by a factor of 10^(3) over the error rate determined solely by selectivity (1.8×10^(-4) [BNID 105213])." Proofreading decreases transcription error rate a 1000 fold.
Entered by Uri M
ID 105214