Crosstalk between Met and Ser/Thr/Tyr might be related to the nature/extent of conservation of Met in proteins. (I) Met could play a regulatory role (crosstalk) (for example, senescence associate protein: AT1G66580) when it is conserved across species. (II) It might play only a structural role in a protein (for example, ATPase F1º AT4G04640), present as a hydrophobic residue. (III-V) If either the phosphorylation site or the Met residue itself is not conserved, it is unlikely that crosstalk will evolve in such proteins (for example, Poly(A) binding protein: AT3G16380.1; peptidylprolyl cis/trans isomerase: AT2G18040.1; P450 reductase: AT4G24520.1). Crosstalk can also depend on the distance between phosphorylation site and Met residue in the 1° sequence, and the 3° structural context. (ara: Arabidopsis thaliana, gly: Glycine max, ory: Oryza sativa, pin: Pinus Taeda, Sel: Selaginella moellendorffii, phy: Physcomitrella patens, chl: Chlamydomonas reinhardtii, and cya: Cyanidioschyzon merolae).