EMS Mutagenesis of Arabidopsis Seeds

The ethylating agent ethyl methanesulfonate (EMS) is widely used for inducing random point mutations. In Arabidopsis, treatment with EMS causes GC-to-AT transitions with great efficiency: it has been estimated that a population of 50,000 well-mutagenized plants harbors one or more transitions in almost every GC pair of the genome. These properties, combined with ease of use, make EMS a mutagen of choice for genetic screens. Here, we describe a protocol for mutagenizing Arabidopsis seed with EMS. In addition, we briefly consider the germ line sectors typically induced by this treatment, and approaches for estimating the rate of induced mutations.