Since ,70% of the strains in this library exhibit growth defects in the presence of dox (,20% of which exhibit growth defects even in the absence of dox, presumably as a result of endogenous promoter replacement) [27] and because BMV RNA replication levels are often non-specifically enhanced in slow-growing cells, stringent growth requirements were employed to minimize false positives. Additionally, because we expected some strains to exhibit either immediate dox-induced growth defects and/or transcriptional defects from the GAL promoter, Fluc values in untreated vs. dox-treated strains were closely monitored. Accordingly, to be included in the final data analysis for potentially specific effects on BMV replication, each strain was required to: 1) double at least twice between 0-24 hr in galactose-containing media; 2) double at least one additional time between 24-48 hr in galactose-containing media; 3) and have an Fluc dox-treated value within 20% of its Fluc untreated value. As a reference, wild type strain R1158 doubled 3 times between 0-24 hr and 2 times between 24-48 hr and had comparable Fluc untreated and Fluc dox-treated values. Strains that did not meet these growth or Fluc value requirements in both passes were excluded from further analysis (Tables S2 and S3 ). The remaining strains that satisfied these growth and Fluc requirements and were included in analysis (Table S4) showed .90% overlap between pass 1 and 2 at the 24 hr time point and .80% overlap between passes at the 48 hr time point, confirming good reproducibility of screen conditions (e.g. growth, dox-treatment, etc.) and assay performance.