Study of the effect of rolC and trolC genes on chlorosis in Tobacco plants

The rol (rooting locus) genes are located on T-DNA (Transferred DNA) of Agrobacterium rhizogenes and induce the morphological and developmental abnormalities upon the integration in to the plant genome. In this study we investigated the effect of bacterial rolC gene and its homologue in Tobacco -tobacco rolC or ''trolC'' gene- on growth of Nicociana tabaccum cv.samsun plants. In the first time, the presence of rolC and trolC genes was confirmed in transgenic lines and then using RT-PCR technique, we have shown that the transgenic plants expressing the bacterial rolC or tobacco trolC genes -which demonstrate the chlorotic phenotype-, have very low or no expression of the chloroplastic gene ''psbA''. This gene encodes for one of the proteins of photosystem II. We conclude that the lack of expression of chloroplastic psbA gene and thus the defective feature of chloroplasts in rolC/trolC transgenic plants may cause the chlorotic phenotype of these plants.