Loading...
  • metabolism
  • Here, and in the accompanying poster, we summarize the current understanding of cytokinin metabolism, transport and signaling, and discuss how this phytohormone regulates changes in gene expression to mediate its pleiotropic effects. (biologists.org)
  • RNASeq analysis of infected tissue showed that host cytokinin metabolism was strongly down-regulated both at the onset and late stages of gall formation. (springer.com)
  • Schematic model of cytokinin metabolism. (fu-berlin.de)
  • The maize beta-D-glucosidase Zm-p60.1 releases active cytokinins from their storage/transport forms, and its over-expression in tobacco disrupts zeatin metabolism. (ibp.cz)
  • Preferential cleavage of specific isomer-conjugates and the capacity to manipulate such preferences will allow the development of powerful tools for detailed probing and fine-tuning of cytokinin metabolism in planta. (ibp.cz)
  • To elucidate the role of ADK in the cytokinin metabolism of tobacco BY-2 cells ( Nicotiana tabacum cv. (ugent.be)
  • and dihydrozeatin riboside (K-m 0.30 - 8.71 mu M). The V-max/K-m values suggest that ADK2S exhibits in vitro an overall higher efficiency in the metabolism of cytokinin ribosides than the other three isoforms. (ugent.be)
  • We suggest that the increased transcript accumulation of NtADK coupled to an increased ADK activity just prior to mitosis is associated with a very active cytokinin metabolism at that phase of the cell cycle of synchronized TBY-2 cells. (ugent.be)
  • auxin
  • We hypothesize that the effect of cytokinin on the development of primordia possibly depends on the robustness and stability of the auxin gradient. (plantcell.org)
  • Cytokinins were discovered in a search for factors that promote cell proliferation in cultured plant cells in concert with a second phytohormone, auxin. (biologists.org)
  • Gall formation is thought to involve perturbations in phytohormone homeostasis, particularly of auxin and cytokinin and more recently brassinosteroids, contributing to the altered morphogenic processes within the root and hypocotyl (Ludwig-Müller et al. (springer.com)
  • The physiology associated with this sequence had been partially characterised in the closely related Funaria hygrometrica and, for example, shown to involve auxin [ 2 ] and cytokinin [ 3 ]. (prolekare.cz)
  • Preferably, the characteristics modified by the present invention are cytokinin-mediated and/or auxin-mediated characteristics. (allindianpatents.com)
  • nucleotide
  • d) a gene encoding a protein which consists of an amino acid sequence derived from the amino acid sequence as shown in any one of SEQ ID NOS: 2, 4, 6, 8, 10, 12, 14 and 16 by deletion, substitution or addition of one or several amino acid residues and has activity of catalyzing reactions that synthesize active cytokinins from nucleotide cytokinins. (google.com)
  • Mutagenesis
  • The role of the active-site microenvironment in fine-tuning Zm-p60.1 substrate specificity has been explored, particularly in the W373K mutant, using site-directed random mutagenesis to investigate the influence of amino acid changes around the 373 position. (ibp.cz)
  • ribosides
  • but cytokinins can also exist in inactive forms as ribosides (in which a ribose sugar is attached to the N 9 nitrogen of the purine ring) and as ribotides (in which the ribose moiety contains a phosphate group). (biologists.org)
  • responses
  • Enhanced cytokinin responses in pericycle cells between existing LRP might restrict LRI near existing LRP and, when compromised, ectopic LRI occurs. (plantcell.org)
  • The phytohormone cytokinin plays diverse roles in plant development, influencing many agriculturally important processes, including growth, nutrient responses and the response to biotic and abiotic stresses. (biologists.org)
  • Analysis of cytokinin precursors, active components and conjugates by microanalytical techniques was consistent with these transcriptional responses. (springer.com)
  • deficiency
  • We isolated several recessive and dominant second-site suppressor alleles termed rock ( repressor of cytokinin deficiency ), which we currently map and functionally characterise. (fu-berlin.de)
  • Phenotypic analysis of the rock2, rock3, and rock4 mutants in the CKX1 overexpressing background revealed that the mutations caused a partial to full reversion of the cytokinin deficiency syndrome in matters of rosette diameter, shoot height, number of siliques, and root growth, and caused delayed leaf senescence in a dark-induced senescence assay. (fu-berlin.de)
  • perturbations
  • Furthermore, our results demonstrate that young LRP are more sensitive to perturbations in the cytokinin activity than are developmentally more advanced primordia. (plantcell.org)
  • mutants
  • Intriguingly, plasmodial development was slowed and spore viability reduced in these mutants indicating a potential role for cytokinins in plasmodial development. (springer.com)
  • In addition, the characterisation of the gain-of-function cytokinin mutants rock2, rock3, and rock4 revealed that an enhanced cytokinin status causes several effects on plant development, which are of potential interest for agricultural breeding purposes, for example an enhanced organ growth and delayed senescence. (fu-berlin.de)
  • processes
  • The question, which plant developmental programs are under cytokinin control and which molecular mechanisms underlie cytokinin action in these processes, is in the focus of our research. (fu-berlin.de)
  • Taken together, the rock2, rock3, and rock4 mutations are interesting tools to research the effects of an enhanced cytokinin status during plant development and gave new insight into cytokinin regulated processes. (fu-berlin.de)
  • Regulation
  • Members of each gene family were characterised by distinct expression profiles during berry development and in different grapevine organs, suggesting a complex regulation of cellular cytokinin activities throughout the plant. (biomedcentral.com)
  • The pre- and post-veraison-specific expression of different members from each of five gene families suggests a highly complex and finely-tuned regulation of cytokinin concentrations and response to different cytokinin species at particular stages of fruit development. (biomedcentral.com)
  • plants
  • However, only in plants and the protist Dictyostelium have cytokinins been definitively shown to act in cellular signaling. (biologists.org)
  • The impact of pathogen-derived cytokinins on the total cytokinin content of infected tissue and host gene expression was minimal in wild type plants. (springer.com)
  • Faiss M, Zalubìlová J, Strnad M, Schmülling T (1997 ) Conditional transgenic expression of the ipt gene indicates a function for cytokinins in paracrine signaling in whole tobacco plants. (publish.csiro.au)
  • In most cases, transgenic pAHK2:rock2 and pAHK3:rock3 lines showed more prominent phenotypes compared to rock2 and rock3 mutant plants, indicating a higher cytokinin status in the transgenic lines. (fu-berlin.de)
  • initiation
  • Here, we show that the early phases of lateral root organogenesis, including priming and initiation, take place in root zones with a repressed cytokinin response. (plantcell.org)
  • isolation
  • BACKGROUND: We have developed a new analytical approach for isolation and quantification of cytokinins (CK) in minute amounts of fresh plant material, which combines a simple one-step purification with ultra-high performance liquid chromatography-fast scanning tandem mass spectrometry. (usda.gov)
  • In order to accomplish this objective, a sequence of methods was developed which allowed the isolation, purification and rigorous chemical identification of cytokinins at the sub-microgram level. (oregonstate.edu)
  • development
  • Cytokinins are known to play an important role in fruit set and early fruit growth, but their involvement in later stages of fruit development is less well understood. (biomedcentral.com)
  • onset
  • These results suggest that the depletion of cytokinins is unlikely to explain the tightly regulated onset of autumn leaf senescence in aspen. (diva-portal.org)
  • levels
  • Senescence was furthermore not connected to the depletion of either active or total cytokinins levels. (diva-portal.org)
  • Certain plant-associated prokaryotes such as Corynebacteriurn fascians and Agrobacterium tumefaciens are known to produce substantial levels of cytokinins. (oregonstate.edu)
  • In view of the fragmentary and presumptive evidence available on the quantitative and qualitative levels of cytokinins produced by A. tumefaciens, it was decided to conduct a study of the cytokinins produced by A. tumefaciens. (oregonstate.edu)
  • transport
  • An updated model for the spatial organisation of cytokinin transport form activation, intracellular trafficking and signalling from the ER is proposed. (publish.csiro.au)