Journal ArticleDOI
A role for gibberellic acid in orienting microtubules and regulating cell growth polarity in the maize root cortex
TLDR
It is shown that gibberellins are morphogenetically active substances, not only in shoots but also in roots of maize, and that the meristem and immediate post-mitotic zone were the targets of gibBerellin deficiency.Abstract:
The role of gibberellins and cortical microtubules in determining the polarity of cell growth in the root cortex of maize (Zea mays L.) was examined. Inhibition of gibberellin biosynthesis, either naturally through mutation (d5 mutant) or by means of chemicals such as 2S,3S paclobutrazol, caused thickening of root apices and increased their starch content. Immunofluorescence microscopy of cortical microtubules, coupled with a comparison of cell widhts, lengths and shapes, indicated that the meristem and immediate post-mitotic zone were the targets of gibberellin deficiency. Cortical cells in these regions were impaired in their ability to develop highly ordered transversal arrays of cortical microtubules. Consequently, the cells became wider and shorter. Application of gibberellic acid re-established the arrangements of cortical microtubules and the polarity of cell growth characteristic for roots having normal levels of gibberellins, it also decreased the starch content. These results indicate that gibberellins are morphogenetically active substances, not only in shoots but also in roots of maize.read more
Citations
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Book ChapterDOI
Triazoles as Plant Growth Regulators and Stress Protectants
R A Fletcher,A Gilley +1 more
Journal ArticleDOI
Cellular Differentiation Regulated by Gibberellin in the Arabidopsis thaliana pickle Mutant
Joe Ogas,Jin-Chen Cheng,Jin-Chen Cheng,Z. Renee Sung,Z. Renee Sung,Chris Somerville,Chris Somerville +6 more
TL;DR: In a screen for mutants, Arabidopsis plants carrying a mutation designated pickle (pkl) were isolated in which the primary root meristem retained characteristics of embryonic tissue.
Journal ArticleDOI
Gibberellins : perception, transduction and responses
TL;DR: As the understanding of GA-regulated events in aleurone cells has advanced through molecular and cell biology approaches, other GA-responsive plant tissues have also proved to be tractible for studying GA-action.
Journal ArticleDOI
Regulation of Root Growth by Plant Hormones—Roles for Auxin and Gibberellin
TL;DR: The classical views of root-growth regulation by auxin and gibberellin are summarized and current theory of the regulation mechanism is described in this review, which focuses on the concentration-dependent deceleration of root growth.
Journal ArticleDOI
REPRESSION OF SHOOT GROWTH, a bZIP Transcriptional Activator, Regulates Cell Elongation by Controlling the Level of Gibberellins
Jutarou Fukazawa,Tatsuya Sakai,Sarahmi Ishida,Isomaro Yamaguchi,Yuji Kamiya,Yohsuke Takahashi +5 more
TL;DR: The results show that RSG, a bZIP transcriptional activator, regulates the morphology of plants by controlling the endogenous amounts of GAs.
References
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Journal ArticleDOI
Specific patterns of cortical and endoplasmic microtubules associated with cell growth and tissue differentiation in roots of maize (Zea mays L.)
TL;DR: Indirect immunofluorescence using α-tubulin antibodies applied to sections of maize roots prepared using low melting point wax was found to give excellent visualisation of both cortical and endoplasmic microtubule (MT) arrays, which allows these arrays to be investigated in cells of the different tissues at various stages of their growth and development.
Journal ArticleDOI
Microtubules, protoplasts and plant cell shape
TL;DR: The observations are best explained by a model in which hooped bundles of microtubules—which are directly or indirectly associated with molecules involved with cellulose biosynthesis at the cell surface—act as an essential template or scaffolding for the orientated deposition of cellulose.
Journal ArticleDOI
Reorientation of Microfibrils and Microtubules at the Outer Epidermal Wall of Maize Coleoptiles During Auxin‐Mediated Growth
TL;DR: It is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface, and reinduction of growth by exogenous auxin
Journal ArticleDOI
Mechanism of Gibberellin-Dependent Stem Elongation in Peas
TL;DR: The results suggest that wall expansion in peas is better viewed as a chemorheological, rather than a viscoelastic, process.
Journal ArticleDOI
Postmitotic 'isodiametric' cell growth in the maize root apex.
TL;DR: The onset of rapid cell elongation occurred at different distances from the apex in various tissues of the primary root of maize, and therefore a distinct region could be distinguished in every examined maize root tissue, which was denoted the region of postmitotic ‘isodiametric’ cell growth.