Identification of components in disease-resistance signaling in Arabidopsis by map-based cloning

With the whole genome sequence and thousands of defined polymorphisms between ecotypes available, it has become much easier to clone a gene by position (map-based cloning) in Arabidopsis. Recent development of DNA-isolation methods in plants also dramatically facilitated large-scale processing of DNA samples. Here, we describe detailed protocols for each step on general scheme of map-based cloning, from mutagenesis to genetic analysis, from rough mapping to fine mapping, and at the end to cloning the gene. Not only can these methods be used to isolate genes that are involved in plant innate immunity, they can also be adapted for any forward genetics projects in Arabidopsis.