Neovascularization during leafy gall formation on Arabidopsis thaliana upon Rhodococcus fascians infection.

摘要: Main conclusion Extensive de novo vascularization of leafy galls emerging upon Rhodococcus fascians infection is achieved by fascicular/interfascicular cambium activity and transdifferentiation parenchyma cells correlated with increased auxin signaling. A gall consisting fully developed yet growth-inhibited shoots, induced the actinomycete fascians, differs in structure compared to callus-like other bacteria. To get insight into vascular development accompanying emergence gall, anatomy infected axillary regions inflorescence stem wild-type Arabidopsis thaliana accession Col-0 plants response pDR5:GUS-tagged were followed time. Based on our observations, three phases can be discerned during symptomatic tissue. First, existing fascicular becomes activated interfascicular formed giving rise secondary elements a basipetal direction below site main an acropetal entire side branch. Then, region between both stems transdifferentiate acropetally towards surface developing tissue leading formation xylem vascularize hyperplasia as they expand. Finally, also without any specific resulting excessive vasculature disorderly distributed gall. Prior apparent anatomical changes, strong mounted, implying that signal controls differentiation infection. conclude, we propose “sidetracking hypothesis” discuss mechanisms driving superfluous