Molecular Basis of Plant Vernalization Revealed By Systems Analysis of the Genes Controlling the Process in Chickpea

Plants have evolved many systems to sense and adapt their growing environments and to modify their growth and development accordingly. Vernalization is one of such systems by which plants promote their flowering through a prolonged exposure to cold temperature. Over the past century, the process of vernalization has been studied extensively and a few of genes involved in the process have been cloned recently. However, little is known about its molecular basis due to its complexity and control by multiple genes. Here, we investigated the molecular basis of vernalization in chickpea by systems analysis of the transcriptomes and related genome sequences of 24 wild and domesticated accessions grown under the condition of prolonged exposure to cold temperature that led to advanced flowering by up to several weeks. We first identified the genes controlling the process using a genome-wide high-throughput gene/QTL cloning system that we developed recently. Then, we studied the interactions and networks of the vernalization genes using their expression profiles. Finally, we examined the molecular basis of vernalization using the genes and their interaction networks controlling the process. We have also investigated the molecular basis of the process leading to the domestication and evolution of chickpea from the naturally autumn wild species to the modern cultivated spring species. These results provide not only novel insights into the molecular bases of plant vernalization and domestication, but also strategies and toolkits for enhanced manipulation of plant vernalization, such as switching the modern spring chickpea back to the autumn chickpea.