Figure 6.

Extension of dinucleotides. The products of dinucleotide extension assays containing [α-³²P]CTP and 10 μM 20-base oligonucleotide (5′-GGGTCX₁₅) were analyzed as described in Fig. 4. The relative amounts of tri- and tetranucleotide synthesized were normalized assuming one labeled nucleotide per two labeled nucleotides per trinucleotide (ACC) and three labeled nucleotides per tetranucleotide (ACCC). Rates of dinucleotide extension are reported at various dinucleotide (AC) concentrations for reactions containing the primase fragment (○), the 63-kDa gene 4 protein (•), or the 63-kDa gene 4 protein in the presence of 1 mM dTTP (▴).