Genome scanning for identification and mapping of receptor-like kinase (RLK) gene superfamily in Solanum tuberosum .

Receptor-like kinases (RLKs) are a key class of genes that contribute to diverse phenomena from plant development to defense responses. The availability of completed potato genome sequences provide an excellent opportunity to identify and characterize RLK gene superfamily in this lineage. We identified 747 non-redundant RLK genes in the potato genome that were classified into 52 subfamilies, of which 58% members organized into tandem repeats. Nine of potato RLK subfamilies organized into tandem repeats. Also, six subfamilies exhibited lineage-specific expansion compared to Arabidopsis. The majority of RLK genes were physically organized within heterogeneous and homogeneous clusters on chromosomes and were unevenly distributed on the genome. Chromosome 2, 3 and 7 contained the highest number of RLK genes and the most underrepresented chromosomes were chromosome 8, 10 and 11. Taken together, our results provide a framework for future efforts on comparative, evolutionary and functional studies of the members of RLK superfamily.