Fig. 6

Growth and Secretion defects in cdc42 mutant alleles. a Temperature-dependent growth of cdc42 mutants. Equal densities of wild-type or cdc42 mutant cells were spotted in tenfold serial dilutions from left to right on YPD plates and incubated at 25 °C or 37 °C. cdc42-303 and cdc42-305 had severe growth defects at 37 °C. b cdc42-303 and cdc42-305 have Bgl2 secretion defects at both 25 °C and 37 °C. Wild-type and cdc42 mutants are grown in YPD at 25 °C to early log phase and then grown at 25 °C or shifted to 37 °C for 90 min. The internal and external pools of Bgl2 are detected by Western blot using anti-Bgl2p antibody. c cdc42-303 has invertase secretion defects at both 25 °C and 37 °C. *p < 0.001 d Thin-section transmission EM of wild type, cdc42-303 and cdc42-305. Cells were grown at 25 °C and shifted at 37 °C for 90 min. e Quantification of cells who have large amount of secretion vesicles in GY3670 (cdc42-303) and GY3672 (cdc42-305). 10 cells were counted for each group. Error bars represent standard deviations. The representative results from three independent experiments are shown