Potato transformation by T-DNA Cytokinin synthesis gene

Cloning an ipt gene from Agrobacterium tumefaciens: characterisation of cytokinins in derivative transgenic plant tissue

“…The levels of iP and iPA were also shown to increase, and again, if only anti-ZR antibodies are used [8,42,43] these compounds will remain undetected . As with our analyses, others have noted that the relative increases in the non-hydroxylated cytokinins were less than the increases of the monitored hydroxylated cytokinins [7,29,36,40,48], indicating that trans-hydroxylation is not rate-limiting in the ipt-transformed tissues .…”

“…[36] Ondrej et al . [29] showed a 2 .8-to 6 .4-fold increase in total cytokinin level in transgenic potato teratomas .…”

“…The introduction of such isopentenyl transferase (ipt) genes into the plant genome results in elevated levels of cytokinin in the tissue [7,25,29,36,42,43,48] . Due to the detrimental effects on plant development of large, constitutive increases in cytokinin, several groups have attempted to control the level of isopentenyl transferase production by the addition of inducible promoters to the ipt coding region .…”

“…rhizogenes system would be of use in qualitatively determining the activity of the ipt gene sequence . Finally, we hoped to circumvent the difficulty other groups had had achieving root formation on shoots transformed with an ipt gene [e .g ., 26,29,36,48] by exploiting the ability of A . rhizogenes infected tissue to form roots as part of hairy root disease .…”

Plant-Bacterium Interactions as a Tool to Study the Functional Aspects of Phytohormones in Higher Plants

“…Constitutive production of cytokinins from fusion of the ipt gene to a constitutive promoter, produced shooty plants which apparently failed to root (13)(14)(15).…”