REMI (Restriction Enzyme Mediated Integration) and its impact on the isolation of pathogenicity genes in fungi attacking plants

Development of molecular techniques for phytopathogenic fungi aims at the i dentification of fungal genes whose products are essential for successful i nfection of the host plant. Initial approaches have relied on isolating can didate genes and generating null-mutations by homologous recombination. Unf ortunately, the results of this strategy have not been overly successful. T his has led to a search for alternatives which allow an unbiased identifica tion of pathogenicity genes. One method, which has proved successful in sev eral systems, is a tagging mutagenesis procedure termed restriction enzyme mediated integration (REMI). In this mini-review we describe this procedure and review its features and results of its use when applied to the identif ication of fungal genes required for disease development in planta.