Pulsed-labeling hydrogen exchange on the ribonuclease H family show that the major folding intermediate is conserved over three billion years of evolution, but the path leading to this intermediate varies.
Reconstructing ancestral enzymes has revealed that a switch in kinase substrate preference evolved via an expanded specificity intermediate that is tolerated in vivo, thus providing a path for kinase diversification.
Experimentally reconstructing the evolution of the molecular complex that animals use to orient the mitotic spindle establishes a simple genetic and physical mechanism for the emergence of a function essential for multicellularity.
In the ancestor of mammals, a multifunctional innate immune protein evolved when a mutation enhanced the protein’s pro-inflammatory activity and proteolytic regulation without disrupting the protein’s antimicrobial activity.
In-planta ancestral protein resurrection of the female determinant of self-incompatibility specificity in Arabidopsis halleri demonstrates that two allelic variants currently segregating as distinct receptor-ligand combinations diverged through an asymmetrical process.