Table 2.

Variables that can modulate the efficiency of correcting replication errors.

Reduced proofreading by:

Mutational inactivation of 3′ exonuclease

Inhibiting 3′ exonuclease activity - dNMPs

Suppressing proofreading by:

Reducing switching from polymerase to exonuclease active site

Promoting MM extension by:

Polymerase active site mutations

High concentration of next correct dNTPs

Mismatch mimicry of correct base pairing

Internalizing a mismatch in a repetitive sequence

Reduced mismatch repair by:

Mutational inactivation of MMR proteins

Cadmium inhibition of MMR in S. cerevisiae

Promoter hypermethylation to silence expression of human Mlh1

Saturation of MMR

Rapid replication in proofreading-defective E. coli (MutD)

DNA damage

Imbalanced expression of MMR proteins

human Msh3

S. cerevisiae Mlh1