C, Phosphorylation of TOC1 is eliminated or largely reduced in 5X and S175A. Total protein extracts (ZT13) from 10-day-old seedlings grown under 12h/12h light/dark cycles were subject to heat (30ºC 20min), pyrophosphatase (PP) and NaF/Na3VO4 (phosphatase inhibitors) treatments. TOC1-GFP at different phosphorylation states were separated by 8% SDS-PAGE (acrylamide:bisacrylamide 150:1) and subsequently detected by α-GFP. 