Misexpression of adv-1 suppresses the phenotype of the Δpp-1 mutant. (A) qRT-PCR data showing mRNA expression levels of adv-1 and pp-1 in Δadv-1 (Ptef1-adv-1-v5; his-3 (MEadv-1)) and Δadv-1 (Ptef1-pp-1-v5; his-3 (MEpp-1)) germlings (left panel) and in Δpp-1 (Ptef1-adv-1-v5; his-3 (MEadv-1)) and Δpp-1 (Ptef1-pp1-v5;his-3 (MEpp-1)) germlings (right panel) compared to the wild-type parental strain. (B) Mean height of aerial hyphae of strains in (A) 3 days after inoculation (ANOVA + Tukey HSD, P < 0.0001, n = 6). (C) Mean growth rate per 24 hr of strains in (A) measured over 4 days (ANOVA + Tukey HSD, P < 0.01, n = 3). (D) Mean frequency of communication and fusion between pairs of germlings for each strain in A (n = 3, 400–700 germling pairs counted per sample). For all bar plots, error bars indicate SD. Photos of the (E) germlings (Bar, 5 μm) and (F) hyphae (Bar, 10 μm) are shown for each strain in A. Arrows indicate chemotropic interactions and successful cell fusion. Lowercase letters in panels B and C denote the result of the ANOVA + Tukey HSD statistical tests.