Fig. 1
From: Inferring Methionine Sulfoxidation and serine Phosphorylation crosstalk from Phylogenetic analyses
Diagram of the Markovian model of evolution for a pair of PTM sites. For two binary traits, four combined states are possible. Each state is defined by an ordered pair where the first entry is either 0 or 1 depending on the absence or presence, respectively, of a phophorylatable residue at the considered position (trait X). The second entry of the pair again will be 0 or 1 depending now on the absence or presence of a methionyl residue at the analyzed position (trait Y). The allowed transitions between states are indicated by the arrows and their associated rate parameters, qij