Fitness effects of the Spok block. (A) Diagram of the genotypes and phenotypes of strains used for the fitness assay. Genotypes are illustrated with location of the Spok genes and Spok blocks on their respective chromosomes. Within the Spok block, Spok3 is marked in green and Spok4 is marked with red. Spok2 (orange) is not located within a Spok block but is present in all strains, so it does not cause spore killing. (B) Violin plots showing the total amount of ascospores collected from crosses of the isogenic strains possessing various iterations of the Spok block, where Psk1 and Psk7 refer to strains Psk1xS14 and Psk7xS14, respectively. The mating type is indicated by a + or − after the strain name. The mat+ parent was always used as the maternal strain in crosses. Yields obtained in crosses where spore killing occurs are shown in red; crosses with no spore killing are in blue. Letters mark the results of an ANOVA as analyzed with a Tukey's HSD test. Dots indicate replicate values (jittered).
