Čeština
EnglishAtSOFL1 and AtSOFL2 Act Redundantly as Positive Modulators of the Endogenous Content of Specific Cytokinins in Arabidopsis.
Zhang J.Y., Vaňková R., Malbeck J., Dobrev P.I., Xu Y.Y., Chong K., Neff M.M.
PLOS ONE 4(12): : e8236, 2009
Keywords: AtSOFL1, AtSOFL2, cytokinin, Arabidopsis
Abstract: Although cytokinins have been known for decades to play important roles in the regulation of plant growth and development, our knowledge of their metabolic system remains limited. Here we characterized two SOB five-like (SOFL) genes, AtSOFL1 and AtSOFL2, in Arabidopsis (Arabidopsis thaliana) and showed that they acted redundantly in regulating specific cytokinin levels. Analysis of the translational fusion AtSOFL1:AtSOFL1-GUS and AtSOFL2:AtSOFL2-GUS indicated that AtSOFL1 and AtSOFL2 exhibited similar expression patterns. Both of them were predominantly expressed in the vascular tissues of developing leaves, flowers and siliques, but barely detectable in roots and stems. Overexpression of either AtSOFL1 or AtSOFL2 led to increased cytokinin content and obvious corresponding mutant phenotypes for both transgenic seedlings and adult plants, whereas silencing or disrupting either of them caused no obvious developmental defects. Endogenous cytokinin analysis, however, revealed that compared to the wild type control, the SOFL1-RNAi62/sofl2-1 double mutant accumulated lower levels of trans-zeatin riboside monophosphate (tZRMP) and N6-(∆2-isopentenyl)adenosine monophosphate (iPRMP), which are biosynthetic intermediates of bioactive cytokinins. The double mutant also displayed slightly decreased response to exogenous cytokinin in both callus-formation and hypocotyl-elongation assays. Taken together, our data suggest that in plants AtSOFL1 and AtSOFL2 work redundantly as positive modulators in the fine-tuning of specific cytokinin levels.
DOI:
IEB authors: Radomíra Vaňková
PLOS ONE 4(12): : e8236, 2009
Keywords: AtSOFL1, AtSOFL2, cytokinin, Arabidopsis
Abstract: Although cytokinins have been known for decades to play important roles in the regulation of plant growth and development, our knowledge of their metabolic system remains limited. Here we characterized two SOB five-like (SOFL) genes, AtSOFL1 and AtSOFL2, in Arabidopsis (Arabidopsis thaliana) and showed that they acted redundantly in regulating specific cytokinin levels. Analysis of the translational fusion AtSOFL1:AtSOFL1-GUS and AtSOFL2:AtSOFL2-GUS indicated that AtSOFL1 and AtSOFL2 exhibited similar expression patterns. Both of them were predominantly expressed in the vascular tissues of developing leaves, flowers and siliques, but barely detectable in roots and stems. Overexpression of either AtSOFL1 or AtSOFL2 led to increased cytokinin content and obvious corresponding mutant phenotypes for both transgenic seedlings and adult plants, whereas silencing or disrupting either of them caused no obvious developmental defects. Endogenous cytokinin analysis, however, revealed that compared to the wild type control, the SOFL1-RNAi62/sofl2-1 double mutant accumulated lower levels of trans-zeatin riboside monophosphate (tZRMP) and N6-(∆2-isopentenyl)adenosine monophosphate (iPRMP), which are biosynthetic intermediates of bioactive cytokinins. The double mutant also displayed slightly decreased response to exogenous cytokinin in both callus-formation and hypocotyl-elongation assays. Taken together, our data suggest that in plants AtSOFL1 and AtSOFL2 work redundantly as positive modulators in the fine-tuning of specific cytokinin levels.
DOI: