Fig. 1

Lack of Phr1p affects morphology and constitutively activates MAP kinase signaling pathways during induction of hyphal growth in C. albicans. a Western blot analysis of Phr1p accumulation. At time zero, blastospores of the wild type (CAI10) were shifted to M199-150 mM HEPES buffered at pH 7.5 at 37 °C. Total protein extracts (125 μg) were analyzed using cross-reacting anti-ScGas1p antibodies and anti-actin mAb. The extract from phr1Δ (CAS10) corresponds to 5 h after the shift and shows the absence of Phr1p. b Morphology of the indicated strains during induction of hyphal growth. c Activation of the Map kinases Mkc1p and Cek1p during induction of hyphal growth. Western blot analysis was performed as described in Methods. Mkc1p and Cek1p migrated as bands of ~ 59 kDa and 48 kDa respectively. Their identity was confirmed using MKC1 and CEK1 null mutants (data not shown). d Activation of Hog1p during induction of hyphal growth. Sample “C” represents a control of an extract from vegetative CAI10 cells exposed for 2 min to hyperosmotic shock (0.6 M KCl in minimal medium)