10.1371/journal.pgen.1002282.g001 Alan J. Herr Alan J. Herr Masanori Ogawa Masanori Ogawa Nicole A. Lawrence Nicole A. Lawrence Lindsey N. Williams Lindsey N. Williams Julie M. Eggington Julie M. Eggington Mallika Singh Mallika Singh Robert A. Smith Robert A. Smith Bradley D. Preston Bradley D. Preston Evidence for a threshold of error-induced extinction. Public Library of Science 2011 error-induced 2011-10-06 02:01:07 Figure https://plos.figshare.com/articles/figure/_Evidence_for_a_threshold_of_error_induced_extinction_/397267 <p>A) Entry into error-induced extinction. Mutated <i>pol3</i> alleles were introduced into haploid <i>MSH6</i> and <i>msh6Δ</i> yeast by plasmid shuffling (<a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002282#pgen.1002282.s001" target="_blank">Figure S1</a>), and mutation rates were measured by fluctuation assays and calculated using the maximum likelihood method. Each bar represents the spontaneous mutation rate, expressed as canavanine-resistant (Can<sup>r</sup>) mutants per cell division, conferred by a specific <i>POL3</i> allele in <i>MSH6</i> or <i>msh6Δ</i> cells. Mutation rate values (x 10<sup>−7</sup>) are indicated on each column. Error bars show 95% confidence intervals. WT, wild-type <i>POL3</i>; black, <i>MSH6</i>; gray, <i>msh6Δ</i>; <b>X</b>, no growth. B) Synthetic lethality of strong <i>pol3</i> mutator alleles with <i>msh6Δ</i>. Serial dilutions of haploid yeast containing <i>POL3–URA3</i> and <i>pol3–LEU2</i> plasmids were plated on SC FOA medium to select for cells that spontaneously lost <i>POL3–URA3</i>. Similar numbers of cells (∼10<sup>5</sup>, 10<sup>4</sup> and 10<sup>3</sup>) were plated for each set of alleles in the <i>MSH6</i> and <i>msh6Δ</i> strains. Failed growth of <i>msh6Δ</i> cells carrying <i>pol3-D407A</i> or <i>pol3-01</i> indicates synthetic lethality (right two panels). <i>pol3-F406A</i> and <i>pol3-Y516F</i> also failed to support colony formation in <i>msh6Δ</i> cells (not shown). Note the small size of <i>pol3-D463A msh6Δ</i> colonies.</p>