Role of LONELY GUY genes in indeterminate nodulation on Medicago truncatula.
LONELY GUY (LOG) genes encode cytokinin riboside 5'-monophosphate phosphoribohydrolases and are directly involved in the activation of cytokinins. To assess whether LOG proteins affect the influence of cytokinin on nodulation, we studied two LOG genes of Medicago truncatula. Expression analysis showed that MtLOG1 and MtLOG2 were upregulated during nodulation in a CRE1-dependent manner. Expression was mainly localized in the dividing cells of the nodule primordium. In addition, RNA interference revealed that MtLOG1 is involved in nodule development and that the gene plays a negative role in lateral root development. Ectopic expression of MtLOG1 resulted in a change in cytokinin homeostasis, triggered cytokinin-inducible genes and produced roots with enlarged vascular tissues and shortened primary roots. In addition, those 35S:LOG1 roots also displayed fewer nodules than the wild-type. This inhibition in nodule formation was local, independent of the SUPER NUMERIC NODULES gene, but coincided with an upregulation of the MtCLE13 gene, encoding a CLAVATA3/EMBRYO SURROUNDING REGION peptide. In conclusion, we demonstrate that in M. truncatula LOG proteins might be implicated in nodule primordium development and lateral root formation.
Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Virginie
V
Mortier
Division of Plant Science, Research School of Biology, The Australian National University, Acton, ACT, 0200, Australia.
Anton
A
Wasson
Centre of the Region Haná for the Biotechnological and Agricultural Research, Faculty of Science, Palacký University, 783 71, Olomouc, Czech Republic.
Pavel
P
Jaworek
Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Annick
A
De Keyser
Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Martijn
M
Decroos
Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Marcelle
M
Holsters
Centre of the Region Haná for the Biotechnological and Agricultural Research, Faculty of Science, Palacký University, 783 71, Olomouc, Czech Republic.
Petr
P
Tarkowski
Division of Plant Science, Research School of Biology, The Australian National University, Acton, ACT, 0200, Australia.
Ulrike
U
Mathesius
Department of Plant Systems Biology, VIB, 9052, Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Sofie
S
Goormachtig
D000619:Aminohydrolases; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003583:Cytokinins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D046913:Medicago truncatula / Q000235:genetics* / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics*; D055170:Plant Root Nodulation / Q000235:genetics*; D018517:Plant Roots / Q000254:growth & development; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D053204:Root Nodules, Plant / Q000254:growth & development*; D015854:Up-Regulation
D029681:Arabidopsis Proteins; D003583:Cytokinins; D009687:Nuclear Proteins; D010940:Plant Proteins; D011956:Receptors, Cell Surface; D011494:Protein Kinases; C421783:WOL protein, Arabidopsis; D000619:Aminohydrolases; C000589428:cytokinin riboside 5'-monophosphate phosphoribohydrolase, Arabidopsis
LONELY GUY; cytokinin; nodulation; nodule primordium; root growth