PtaRHE1, a Populus tremula × Populus alba RING-H2 protein of the ATL family, has a regulatory role in secondary phloem fibre development.
REALLY INTERESTING NEW GENE (RING) proteins play important roles in the regulation of many processes by recognizing target proteins for ubiquitination. Previously, we have shown that the expression of PtaRHE1, encoding a Populus tremula × Populus alba RING-H2 protein with E3 ubiquitin ligase activity, is associated with tissues undergoing secondary growth. To further elucidate the role of PtaRHE1 in vascular tissues, we have undertaken a reverse genetic analysis in poplar. Within stem secondary vascular tissues, PtaRHE1 and its corresponding protein are expressed predominantly in the phloem. The downregulation of PtaRHE1 in poplar by artificial miRNA triggers alterations in phloem fibre patterning, characterized by an increased portion of secondary phloem fibres that have a reduced cell wall thickness and a change in lignin composition, with lower levels of syringyl units as compared with wild-type plants. Following an RNA-seq analysis, a biological network involving hormone stress signalling, as well as developmental processes, could be delineated. Several candidate genes possibly associated with the altered phloem fibre phenotype observed in amiRPtaRHE1 poplar were identified. Altogether, our data suggest a regulatory role for PtaRHE1 in secondary phloem fibre development.
Laboratoire de Biotechnologie Végétale, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Fabien
F
Baldacci-Cresp
Laboratoire de Biotechnologie Végétale, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Jihad
J
Moussawi
Unité de Recherche Amélioration Génétique et Physiologie Forestières (UR0588), Institut National de la Recherche Agronomique (INRA), 45075, Orléans Cedex 02, France.
Jean-Charles
JC
Leplé
Department of Plant Systems Biology, VIB, 9052, Ghent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.
Rebecca
R
Van Acker
Unité Mixte de Recherche 1136, Interactions Arbres-Microorganismes, Laboratory of Excellence ARBRE, INRA, 54280, Champenoux, France.|Unité Mixte de Recherche 1136, Interactions Arbres-Microorganismes, Laboratory of Excellence ARBRE, Lorraine University, 54500, Vandoeuvre-lès-Nancy, France.
Annegret
A
Kohler
Laboratoire de Biotechnologie Végétale, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Julie
J
Candiracci
Center for Microscopy and Molecular Imaging-CMMI, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Laure
L
Twyffels
School of Ecosystem and Forest Sciences, The University of Melbourne, Water Street, Creswick, Vic., 3363, Australia.
Antanas V
AV
Spokevicius
School of Ecosystem and Forest Sciences, The University of Melbourne, Water Street, Creswick, Vic., 3363, Australia.
Gerd
G
Bossinger
Unité de Recherche Amélioration Génétique et Physiologie Forestières (UR0588), Institut National de la Recherche Agronomique (INRA), 45075, Orléans Cedex 02, France.
Françoise
F
Laurans
UMR A547 PIAF, Clermont Université, Université Blaise Pascal, BP 10448, 63000, Clermont-Ferrand, France.|UMR A547 PIAF, INRA, 63100, Clermont-Ferrand, France.
Nicole
N
Brunel
Center for Microscopy and Molecular Imaging-CMMI, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.|Laboratoire de Parasitologie Moléculaire, IBMM, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Marjorie
M
Vermeersch
Department of Plant Systems Biology, VIB, 9052, Ghent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.
Wout
W
Boerjan
Laboratoire de Biotechnologie Végétale, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Mondher
M
El Jaziri
Laboratoire de Biotechnologie Végétale, Université Libre de Bruxelles (ULB), 6041, Gosselies, Belgium.
Marie
M
Baucher
D002473:Cell Wall / Q000378:metabolism; D002678:Chimera; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010641:Phenotype; D052585:Phloem / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018547:Plant Stems / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D032107:Populus / Q000235:genetics / Q000254:growth & development*
D010940:Plant Proteins
Populus tremula × Populus alba; PtaRHE1; RING-H2; phloem fibre development; vascular tissues