Table 3.

Kinds and locations of unequivocally independent point mutations induced in the lacZα gene during replication of UV-irradiated M13mp2-oriL by XP variant cell extractsa

MutantPosition(s)bMutationPhotoproduct context (5′→3′)dStrandc
XU6584C · G→A · TCAGTCACGALeading
XU4990C · G→A · TTTTTCCCAGLeading
XU10190C · G→A · TTTTTCCCAGLeading
XU4190C · G→A · TTTTTCCCAGLeading
XU81145C · G→A · TCCAGCTGGCLeading
XU84145C · G→A · TCCAGCTGGCLeading
XU97148C · G→A · TACGCCAGCTLeading
XU47159C · G→A · TTCTTCGCTALeading
XU59162C · G→A · TGCCTCTTCGLeading
XU10588C · G→T · ATTCCCAGTCLeading
XU107107–108C · G→T · A, C · G→T · ATTACCCAACLagging
XU102108C · G→T · ATACCCAACTLagging
XU91108C · G→T · ATACCCAACTLagging
XU66108C · G→T · ATACCCAACTLagging
XU732T · A→A · TCTGTTTCCTLeading
XU7354T · A→A · TGAATTCGTALeading
XU10656T · A→A · TCGAATTCACLagging
XU6767T · A→A · TGCCGTCGTTLagging
XU7473T · A→A · TGTTTTACAALagging
XU2954T · A→C · GGAATTCGTALeading
XU5574–75ΔACTTTTACAACLagging
XU69132–136ΔCCATCCCCCTLagging
  • a The target genes from 45 mutants were sequenced by standard methods. Of these, 10 had no mutation in the target gene and 2 had large deletions. Twelve mutants had mutations that were also found in unreplicated templates, i.e., that represented background mutations. These 12 were omitted from the analysis and from calculations of UV-induced mutant frequency.

  • b The lacZα gene comprises positions −84 to +174, with +40 being the first transcribed nucleotide.

  • c “Strand” refers to the newly synthesized DNA that contains a mutation as a result of error-prone bypass of photoproducts that were located in the corresponding template strand.

  • d The site of the mutation is underlined.