Figure 6.
The Depletion of the Regulatory Subunit of Primase Is Specific to HU Treatment
(A–C) The upper panel shows plating of 10-fold serial dilutions either mock-treated (−) or treated (+) with (A) 200 J/m2 of UV light (254 nm) or (B) 30 μM or (C) 100 μM hydrogen peroxide for the indicated times. The lower panels contain western blots to determine levels of primase and TBP proteins.
(D) Treatment of 13.5 μM recombinant primase (upper panel), MCM (middle panel), or PolB1 (bottom panel) with the indicated concentrations of HU for 4 hr at 78°C leads to selective precipitation of primase. Following treatment, samples were centrifuged to separate soluble (s) and precipitated (p) material and corresponding fractions analyzed by SDS-PAGE and stained with Coomassie brilliant blue.