Skip to main content
Figure 7 | BMC Evolutionary Biology

Figure 7

From: Molecular co-evolution of a protease and its substrate elucidated by analysis of the activity of predicted ancestral hatching enzyme

Figure 7

Model of co-evolution of hatching enzyme and egg envelope protein. (A) Ancestral hatching enzyme (LCE) and egg envelope protein (P2) co-evolved in both Fundulus and medaka lineages. (B) In the medaka lineage, mutation in LCE introduced lower P2 site preference while maintaining the activity of LCE in solubilizing the egg envelope. (C) Then, mutation in egg envelope protein occurred in the medaka lineage, and ancestral Fundulus LCE became unable to digest ancestral medaka egg envelope. (D) In both Fundulus and medaka lineages further substitutions occurred, and strict species specificity was established between the two species.

Back to article page