Discovery of a high-altitude ecotype and ancient lineage of Arabidopsis thaliana from Tibet

Arabidopsis thaliana (A. thaliana) has long been a model species for dicotyledon study, and was the first flowering plant to get its genome completed sequenced [1]. Although most wild A. thaliana are collected in Europe, several studies have found a rapid A. thaliana west-east expansion from Central Asia [2]. The Qinghai-Tibet Plateau (QTP) is close to Central Asia and known for its high altitude, unique environments and biodiversity [3]. However, no wild-type A. thaliana had been either discovered or sequenced from QTP. Studies on the A. thaliana populations collected under 2000 m asl have shown that the adaptive variations associated with climate and altitudinal gradients [4]. Hence a high-altitude A. thaliana provides a precious natural material to investigate the evolution and adaptation process. Here, we present the genome of a new ecotype of A. thaliana collected in the Gongga County, Tibet (4200 m asl) (Fig. 1a), to demonstrate its evolutionary history and adaptation to highaltitude regions.