The susceptible phenotype of selected mutant lines. (A) Three-week-old NB, pish mutant lines, NC8589 andND2043, and ttm mutant lines were inoculated with M. oryzae containing avrPish. The photographs were taken 7 days post inoculation. (B) Expression of the Pish gene. Total RNA was extracted from leaf tissues of NB and each mutant. Samples (1 μg) of poly(A)+ RNA were separated by gel electrophoresis, blotted, and hybridized with radiolabeled probes as indicated. The Actin probe was used as a loading control. The closed arrowhead indicates the size of the Pish mRNA. The asterisk indicates a non-specific signal detected by the Pish probe.