Poster: Plant-pathogen interactions

Abs # 531: A novel approach for identification of host cell factors facilitating Agrobacterium-mediated plant transformation

Presenter:	Anand, Ajith , aanand@noble.org
Authors	Anand, Ajith  (A)   Ryu, Choong-Min  (A)   Kang, Li  (A)   Mysore, Kirankumar S. (A)
Affiliations:	(A): The Samuel Roberts Noble Foundation

DNA transfer between Agrobacterium tumefaciens and plants is the only known trans-kingdom natural DNA transfer. This unique horizontal DNA transfer involves a cascade of events in both bacteria and plants. A better understanding of the bacterial biology in this event has been deciphered and all the bacterial genes involved in this phenomenon will be identified very soon partly due to the completion of the Agrobacterium genome sequencing project. However, host cell factors that facilitate the transformation process involving bacterial attachment, import of the cognate T-DNA into the host cytoplasm and its subsequent nuclear import and stable integration into the host genome is relatively less understood. To provide further insights into the T-DNA transformation process from a plant’s perspective, we are currently employing the powerful tool of virus-induced gene silencing (VIGS) technology to transiently knockout, in planta, both the known and unknown plant factors in Nicotiana benthamiana by using forward and reverse genetic approaches. Subsequent in vitro studies of the knockout mutants using leaf tumor assays and stable transformation assays have validated the role of many already known plant factors including α-importin, VIP1, histone H2B, actin etc. in Agrobacterium-mediated plant transformation. Additional plant factors were identified from our forward genetics screening and are currently under different stages of investigation. We propose that this technology could lead to the identification of many plant factors that otherwise could be deleterious to plants using conventional mutant screening.