Figure 5: Effector secretion and pathogenicity are impaired in hok1 null mutants.
From: Long-distance endosome trafficking drives fungal effector production during plant infection
(a) Phenotype of hok1 deletion mutants. Scale bar, 20 μm. (b) EE localization and motility in hok1 deletion mutants. Upper panel shows EE clusters (GFP-Rab5a, green, arrowheads) at the poles of the short mutant cells. Lower kymograph shows the absence of EE motility in Δhok1 mutants. Scale bars, 20 μm (upper panel), 3 s (vertical, lower panel) and 1 μm (horizontal, lower panel). (c) Plant disease symptoms at 9 days after infection of maize plants with control and Δhok1 strains. (d) Plant symptoms at 14 days after infection with control and hok1 deletion mutants. Mean±s.e. and sample sizes n (=number of experiments (exp)) are shown. *Different from control at error probability P=0.019; **different from control at error probability P=0.0047; unpaired Student’s t-test. (e) Secretion of fluorescent effectors, indicated by the signal intensity at the periphery of the invasive hyphae in plants at 2 d.p.i. Mean±s.e. and sample sizes from one experiment are shown. The result was confirmed by a non-quantitative experiment. *Different from control at Ppep1=0.0184, ***different from control at Pcmu1=0.0002 and Ppit2<0.0001; unpaired Student’s t-test. (f) Relative transcript levels of cmu1, pep1 and pit2 in cells grown in infected plant tissue at 1–2 d.p.i. Effector expression in infecting control strains was set as 100%. Mean±s.e. and sample sizes n (=number of experiments) are shown. **Significance at error probability Pcmu1=0.0021 and Ppep1=0.0096; ***significance at error probability Ppit2<0.0001; unpaired Student’s t-test. (g) Secretion of Cmu1-mCherry in control and Δhok1 mutants. Note that secretion of the effector in Δhok1 mutants is reduced compared with control strain. Scale bar, 5 μm.
