Figure 1. EIN2 phosphorylation and cleavage products based on Qiao et al.3(A) EIN2 in absence of ET (ambient air exposure) and digested with trypsin. EIN2 is phosphorylated (circled p) and remains anchored at the ER. (B) EIN2 in the presence of ET. EIN2 is not phosphorylated and is cleaved in vivo at S645 and the EIN2 C-terminus translocates to the nucleus (prior to trypsin digestion). The bottom bar shows the approximate molecular weight of native EIN2 as measured from the C-terminus. The author contends that the ET-induced cleavage site in model in B is not sufficiently proven by published results.