ИСТИНА

Macromolecular cell-to-cell traffic in plants involves plasmodesmata. The mechanism of intercellular transport is highly adjustable and non-cell-autonomous-pathway protein (NCAPP) is reported to be one of its regulators. This 40 kDa protein is crucial for trafficking of specific non-cell-autonomous proteins (NCAPs) such as CmPP16 and the tobacco mosaic virus movement protein (TMV MP) [J.-Y. Lee et al, 2003]. Recently it has been shown that methanol stress signal can induce dramatic raise of Nicotiana benthamiana NCAPP mRNA accumulation accompanied by increased plasmodesmata gating capacity and enhanced TMV reproduction [Dorokhov et al., 2012]. We hypothesized that NCAPP functions as a carrier to transport TMV MP to plasmodesmata in the infected cells. This point of view suggests that NCAPP is able to interact with the TMV MP physically. To test this hypothesis the renatured blot overlay assay with recombinant NCAPP and MP proteins was performed. Our comprehensive analysis showed specific interaction between these proteins. Identification of MP domains involved in binding is currently underway. Given that methanol stress signal also modified plant immunity in response to bacterial infection we decided to conduct a broader screen of virulence factors. The proteins involved in Agrobacterium tumefaciens pathogenesis will be analyzed in renatured blot overlay assay in order to elucidate NCAP pathway role in plant immunity. The results of these experiments will be reported.