Experimental Examination of EFL and MATX Eukaryotic Horizontal Gene Transfers: Coexistence of Mutually Exclusive Transcripts Predates Functional Rescue

Many eukaryotic genes do not follow simple vertical inheritance. Elongation factor 1α (EF-1α) and methionine adenosyl transferase (MAT) are enzymes with complicated evolutionary histories and, interestingly, the two cases have several features in common. These essential enzymes occur as two relatively divergent paralogs (EF-1α/EFL, MAT/MATX) that have patchy distributions in eukaryotic lineages that are nearly mutually exclusive. To explain such...