The roles of auxin and cytokinin in cell proliferation
Abstract
Plants have evolved an amazing repertoire of mechanisms to respond to alterations in their environment. Part of these adaptation processes is the ability to control organogenesis dependent on environmental parameters. Apparently, the enormous flexibility leading to a variety of plant shapes requires tight control mechanisms. Among those, the decision as to whether a plant cell remains meristematic and undergoes further cell divisions or whether it starts to differentiate is one of the most critical events. Two growth regulators, auxin and cytokinin, are key elements required for the signaling events leading to either cell differentiation or cell division. However, elements of a signal transduction cascade, which integrate the signals of both growth regulators, have not been characterized to date. A combined treatment of plant cells with auxin and cytokinin leads to a pronounced induction of cell division. Based on this phenotype we have characterized two arabidopsis mutants in which the response two both growth regulators is altered. Mutants defective in PROPORZ1 (PRZ1) or PROPORZ2 (PRZ2) respond to either one of the principal regulators of cell division with the formation of meristematic tissue. These findings suggest that the corresponding gene products participate in signaling events controlled by the concerted impact of auxin and cytokinin. A detailed characterization of the PRZ genes is goal of the current project application. Moreover, additional elements involved in PRZ1-dependent signaling should be characterized. From the molecular characterization of the PRZ genes we expect to obtain fundamental insight into the mechanism as to how phytohormones interact with the cell cycle machinery - a critical aspect in plant adaptation processes.
keywords auxin cytokinin cell proliferation Arabidopsis auxin cytokinin cell proliferation Arabidopsis
Publikationen
PROPORZ1, a putative Arabidopsis transcriptional adaptor protein, mediates auxin and cytokinin signals in the control of cell proliferation.
Autoren: Sieberer, T, Seifert, G, Hauser, M-T and Luschnig, C Jahr: 2003
Conference & Workshop proceedings, paper, abstract
Project staff
Christian Luschnig
Assoc. Prof. Dr. Christian Luschnig
christian.luschnig@boku.ac.at
Tel: +43 1 47654-94230
Project Leader
01.01.2002 - 31.12.2004