DNA replication profiling by BrdU Immunoprecipitation of S.cerevisiae wild-type versus H3K37R mutant under over-expression of MCM activators.

Wild-type and isogenic H3K37R yeast cultures were grown in medium containing 2% raffinose as carbone source. Cells were synchronized in G1 with alpha factor. To half culture (100ml), glucose (2% final concentration) and 1.3ml BrdU (50mg/ml stock) and 1.3ml BrdU (50mg/ml stock) was added. To the other half, galactose (2% final concentration) and 1.3ml BrdU (50mg/ml stock). Both flasks were incubated for further 30min at 30C, then cell were collected by centrifugation and resuspended into 100ml of 30C warmed YPA-2%Glucose or YPA-2%Galactose medium containing 25ml HU (2M stock) plus 1.2 ml BrdU (50mg/ml stock) and incubated for 1 hour and 10minutes. YPA-Glucose and YPA-Galactose cultures were immediately transferred to ice/water bath and replication was stopped by addition of NaN3 and cells were processed for DNA immunoprecipitation with anti BrdU antibody.