A new, rapid and efficient transformation procedure for Neurospora.

A new, rapid, efficient and reliable method for transforming Neurospora crassa is described. In this procedure, germinated conidia are treated with lithium acetate, then incubated with DNA, followed by exposure to polyethylene glycol and then a brief heat shock, prior to plating on selective medium. Optimal conditions to achieve a high transformation rate are reported. Transformation can be obtained with both circular and linear plasmid DNA and also with genomic DNA. Although the rate is substantially decreased, transformation was also obtained with relatively impure DNA preparations, such as that made via rapid "miniprep" procedures. This transformation technique is simple and reliable and provides a considerable savings in time and materials.