DspA/E-induced growth arrest and Orm protein dephosphorylation require a functional Cdc55-PP2A phosphatase.
A, serial dilutions of strains BY, Δppm1, and Δcdc55 harboring DspA/E or the EV were spotted on SD-Ura Doxy or SD-Ura plates. Photographs were taken after 48 h of growth. B, FLAG-Orm1 was expressed in BY and Δcdc55 mutant cells expressing DspA/E or not (EV). After 6 h on SD-Ura medium, the cells were lysed, and the resulting extracts were resolved by Phos-tag gels and analyzed by immunoblotting with anti-FLAG. Loading controls on SDS-polyacrylamide gels were analyzed by anti-FLAG or anti-actin antibodies. Controls of BY and Δcdc55 mutant treated with myriocin are also shown.