Primary root protophloem differentiation requires balanced phosphatidylinositol-4,5-biphosphate levels and systemically affects root branching.

Détails

ID Serval
serval:BIB_38D36BB3B696
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Primary root protophloem differentiation requires balanced phosphatidylinositol-4,5-biphosphate levels and systemically affects root branching.
Périodique
Development
Auteur(s)
Rodriguez-Villalon A., Gujas B., van Wijk R., Munnik T., Hardtke C.S.
ISSN
1477-9129 (Electronic)
ISSN-L
0950-1991
Statut éditorial
Publié
Date de publication
2015
Volume
142
Numéro
8
Pages
1437-1446
Langue
anglais
Résumé
Protophloem is a specialized vascular tissue in growing plant organs, such as root meristems. In Arabidopsis mutants with impaired primary root protophloem differentiation, brevis radix (brx) and octopus (ops), meristematic activity and consequently overall root growth are strongly reduced. Second site mutation in the protophloem-specific presumed phosphoinositide 5-phosphatase COTYLEDON VASCULAR PATTERN 2 (CVP2), but not in its homolog CVP2-LIKE 1 (CVL1), partially rescues brx defects. Consistent with this finding, CVP2 hyperactivity in a wild-type background recreates a brx phenotype. Paradoxically, however, while cvp2 or cvl1 single mutants display no apparent root defects, the root phenotype of cvp2 cvl1 double mutants is similar to brx or ops, although, as expected, cvp2 cvl1 seedlings contain more phosphatidylinositol-4,5-biphosphate. Thus, tightly balanced phosphatidylinositol-4,5-biphosphate levels appear essential for proper protophloem differentiation. Genetically, OPS acts downstream of phosphatidylinositol-4,5-biphosphate levels, as cvp2 mutation cannot rescue ops defects, whereas increased OPS dose rescues cvp2 cvl1 defects. Finally, all three mutants display higher density and accelerated emergence of lateral roots, which correlates with increased auxin response in the root differentiation zone. This phenotype is also created by application of peptides that suppress protophloem differentiation, CLAVATA3/EMBRYO SURROUNDING REGION 26 (CLE26) and CLE45. Thus, local changes in the primary root protophloem systemically shape overall root system architecture.
Mots-clé
Arabidopsis, Auxin, CLE peptide, CLE26, CLE45, Lateral roots, Phosphoinositides
Pubmed
Web of science
Open Access
Oui
Création de la notice
21/05/2015 9:26
Dernière modification de la notice
20/08/2019 14:28
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