Fig. 2.

S-nitrosylation of SCE1 Cys139 inhibits SUMOylation in vivo. (A) Protein extracts from 35S::FLAG-SCE1 plants were subjected to the BST with or without preincubation with 1 mM GSNO. Biotinylated proteins were enriched by streptavidin affinity pull-down, followed by Western blot analysis against FLAG. (B) Protein extracts from controls or plants inoculated with 10⁷ cfu/mL Pst DC3000 or Pst DC3000 (avrB) (6 hpi) were subjected to the BST, and both SNO-SCE1 and total SCE1 were detected by Western blot against FLAG. (C) Plants were inoculated as in B, and leaf tissue was collected at 6 hpi. Protein extracts were then analyzed by Western blot analysis against SUMO1/2. Ponceau S staining of the large subunit of Rubisco indicates equal loading. (D) Liquid-grown seedlings of the stated lines were exposed to 37 °C for the indicated times and analyzed as in C.