Concerted evolution is the non-independent evolution of gene copies in a multigene family and can act to homogenize members and prevent acquisition of new function. Despite numerous studies demonstrating evidence for concerted evolution, the mechanism by which it operates is still poorly understood and many questions remain unexplained.
Previous studies have shown a pattern of concerted evolution among the three loci encoding the small subunit of Rubisco (rbcS) in three disparate species of Solanaceae (petunia, tobacco, and tomato) where paralogs (genes related by duplication) are more similar than orthologs (genes related by speciation). In contrast, two closely related species in Solanaceae, tomato and potato, have rbcS orthologs that are more similar than are their paralogs, indicating that speciation is occurring faster than concerted evolution in this lineage.
Two hypotheses have been proposed for the pattern of concerted evolution in Solanaceae:To distinguish betweeen these two hypotheses we are sequencing rbcS copies from species closely related and progressively more distantly related to tomato and potato.
