Cytokinin stress changes the developmental regulation of several defence-related genes in tobacco.

摘要: Tobacco shoots exposed to elevated endogenous or exogenous cytokinin levels are unable develop roots and lack apical dominance. We have isolated cDNA copies of five mRNA species that accumulate in such cytokinin-stressed via differential screening a library transgenic which contain an active T-DNA gene (T-cyt gene) from Agrobacterium tumefaciens. Four the clones were found correspond plant defence-related mRNAs, encoding extensin, chitinase, PR-1 PR-1-like protein, respectively. In normal tobacco plants is relatively rare all organs. The other four mRNAs occur at low shoots, especially leaves, but very prevalent roots. Extensin mRNA, for example, not detectable while it abundant stems. cultured on cytokinin-containing medium levels, similar those T-cyt shoots. conclude imposed stress causes changes tissue-specific control several tobacco.