Figure 8
From: Co-evolutionary networks of genes and cellular processes across fungal species
An illustrative example involves the category of methionine biosynthesis, which has a negative rERP correlation with phosphatidylcholine (PC) biosynthesis, an important and abundant structural component of the membranes of eukaryotic cells. PC is synthesized by three successive transfers of methyl groups from S-adenosyl-methionine to phosphatidyl-ethanolamine [36, 37]; thus, the evolution of PC biosynthetic pathways may be conditioned by the evolution of methionine biosynthesis pathways, and follow it by some time lag. This phenomenon is demonstrated in the subtree below internal node 11 (a). The rERPs of these two GO functions are shown in (b).