Institute of Information Science, Academia Sinica

C4 plants evolved from C3 plants through a series of complex evolutionary steps. The evolution of C4 photosynthesis has been 
considered a story of gene/whole genome duplications and subsequent modifications of gene function. If whole-genome duplication has 
contributed to the evolution of C4 photosynthesis, many other genes should have been duplicated together with these C4 genes. However, 
which genes were co-duplicated with C4 genes and whether they have also played a role in C4 evolution are largely unknown. In this talk, 
we developed a simple method to characterize the historical profile of the paralogs of a gene by tracing back to the most recent common 
ancestor (MRCA) of the gene and the paralog and then counting the number of paralogs at each MRCA. We clustered the genes into clusters with similar duplication profiles and inferred their functional enrichments. Applying our method to maize, a familiar C4 plant, we 
identified many genes that show similar duplication profiles with those of the key C4 genes and studied the functional preferences of 
the identified genes. Our results indicate that the duplication events of some key C4 genes and their related genes had occurred during 
similar time periods. Some of these genes might have co-evolved with the key C4 genes to increase the strength of C4 photosynthesis.