Total protein extraction and immunoblot analysis
The leaves of seedlings were harvested, and total protein was prepared following the methods of Sun et al. (2016). For immunoblot analyses, the proteins were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) (15% acrylamide) (Schägger and von Jagow, 1987). Proteins were then transferred to polyvinylidene difluoride membranes (Ihnatowicz et al., 2004) and probed with their corresponding antibodies. Enhanced chemiluminescence was used for signal detection (GE Healthcare Biosciences).