Agrobacterium T-DNA: a silver bullet for filamentous fungi?

Agrobacterium tumefaciens has been a steadfast servant of the plant research community over the past 25 years. Few would dispute the impact of A. tumefaciens mediated transformation on the identification and isolation of plant genes in both basic research and biotechnology. Indeed, Walden and Schell have described activation T-DNA tagging - the process by which A. tumefaciens mediated transformation is used to overexpress a target gene - as "a silver bullet approach to isolating plant genes." Now, the kingdom of A. tumefaciens has been extended to include the filamentous fungi as well. In this issue, de Groot et al. describe the transformation of several different fungi using an A. tumefaciens-mediated system. Their report details the first documented transformation of a commercial strain of Agaricus bisporus and suggests that A. tumefaciens T-DNA (which shares no homology with fungal DNA) can integrate randomly and as a single copy into fungal chromosomes. The work opens the possibility of designing a "silver bullet" T-DNA gene tagging system for fungi that may one day rival systems used in plants.