Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Current refinement(s):

Records 1 - 6 / 6

  • help
  • print

    Print search results

  • export

    Export search results

  • alert
    We will mail you new results for this query: keywords==Medicago truncatula
Check title to add to marked list
The Medicago truncatula nodule identity gene MtNOOT1 is required for coordinated apical-basal development of the root
Shen, Defeng ; Kulikova, Olga ; Guhl, Kerstin ; Franssen, Henk ; Kohlen, Wouter ; Bisseling, Ton ; Geurts, René - \ 2019
BMC Plant Biology 19 (2019)1. - ISSN 1471-2229
Medicago truncatula - NBCL - NIN - NOOT-BOP-COCHLEATA-LIKE - NOOT1 - Rhizobium susceptible zone - Xylem cell differentiation

Background: Legumes can utilize atmospheric nitrogen by hosting nitrogen-fixing bacteria in special lateral root organs, called nodules. Legume nodules have a unique ontology, despite similarities in the gene networks controlling nodule and lateral root development. It has been shown that Medicago truncatula NODULE ROOT1 (MtNOOT1) is required for the maintenance of nodule identity, preventing the conversion to lateral root development. MtNOOT1 and its orthologs in other plant species -collectively called the NOOT-BOP-COCH-LIKE (NBCL) family- specify boundary formation in various aerial organs. However, MtNOOT1 is not only expressed in nodules and aerial organs, but also in developing roots, where its function remains elusive. Results: We show that Mtnoot1 mutant seedlings display accelerated root elongation due to an enlarged root apical meristem. Also, Mtnoot1 mutant roots are thinner than wild-type and are delayed in xylem cell differentiation. We provide molecular evidence that the affected spatial development of Mtnoot1 mutant roots correlates with delayed induction of genes involved in xylem cell differentiation. This coincides with a basipetal shift of the root zone that is susceptible to rhizobium-secreted symbiotic signal molecules. Conclusions: Our data show that MtNOOT1 regulates the size of the root apical meristem and vascular differentiation. Our data demonstrate that MtNOOT1 not only functions as a homeotic gene in nodule development but also coordinates the spatial development of the root.

NODULE INCEPTION Recruits the Lateral Root Developmental Program for Symbiotic Nodule Organogenesis in Medicago truncatula
Schiessl, Katharina ; Lilley, Jodi L.S. ; Lee, Tak ; Tamvakis, Ioannis ; Kohlen, Wouter ; Bailey, Paul C. ; Thomas, Aaron ; Luptak, Jakub ; Ramakrishnan, Karunakaran ; Carpenter, Matthew D. ; Mysore, Kirankumar S. ; Wen, Jiangqi ; Ahnert, Sebastian ; Grieneisen, Veronica A. ; Oldroyd, Giles E.D. - \ 2019
Current Biology 29 (2019)21. - ISSN 0960-9822 - p. 3657 - 3668.e5.
auxin - CYTOKININ RESPONSE FACTOR - endosymbiosis - LATERAL ORGAN BOUNDARIES DOMAIN - lateral root/nodule organogenesis - Medicago truncatula - nitrogen - NODULE INCEPTION - rhizobia - YUCCA

To overcome nitrogen deficiencies in the soil, legumes enter symbioses with rhizobial bacteria that convert atmospheric nitrogen into ammonium. Rhizobia are accommodated as endosymbionts within lateral root organs called nodules that initiate from the inner layers of Medicago truncatula roots in response to rhizobial perception. In contrast, lateral roots emerge from predefined founder cells as an adaptive response to environmental stimuli, including water and nutrient availability. CYTOKININ RESPONSE 1 (CRE1)-mediated signaling in the pericycle and in the cortex is necessary and sufficient for nodulation, whereas cytokinin is antagonistic to lateral root development, with cre1 showing increased lateral root emergence and decreased nodulation. To better understand the relatedness between nodule and lateral root development, we undertook a comparative analysis of these two root developmental programs. Here, we demonstrate that despite differential induction, lateral roots and nodules share overlapping developmental programs, with mutants in LOB-DOMAIN PROTEIN 16 (LBD16) showing equivalent defects in nodule and lateral root initiation. The cytokinin-inducible transcription factor NODULE INCEPTION (NIN) allows induction of this program during nodulation through activation of LBD16 that promotes auxin biosynthesis via transcriptional induction of STYLISH (STY) and YUCCAs (YUC). We conclude that cytokinin facilitates local auxin accumulation through NIN promotion of LBD16, which activates a nodule developmental program overlapping with that induced during lateral root initiation.

A Medicago truncatula SWEET transporter implicated in arbuscule maintenance during arbuscular mycorrhizal symbiosis
An, Jianyong ; Zeng, Tian ; Ji, Chuanya ; Graaf, Sanne de; Zheng, Zijun ; Xiao, Ting Ting ; Deng, Xiuxin ; Xiao, Shunyuan ; Bisseling, Ton ; Limpens, Erik ; Pan, Zhiyong - \ 2019
New Phytologist 224 (2019)1. - ISSN 0028-646X - p. 396 - 408.
arbuscular mycorrhiza (AM) - glucose - Medicago truncatula - sugar export - SWEET - symbiosis

Plants form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which facilitates the acquisition of scarce minerals from the soil. In return, the host plants provide sugars and lipids to its fungal partner. However, the mechanism by which the AM fungi obtain sugars from the plant has remained elusive. In this study we investigated the role of potential SWEET family sugar exporters in AM symbiosis in Medicago truncatula. We show that M. truncatula SWEET1b transporter is strongly upregulated in arbuscule-containing cells compared to roots and localizes to the peri-arbuscular membrane, across which nutrient exchange takes place. Heterologous expression of MtSWEET1b in a yeast hexose transport mutant showed that it mainly transports glucose. Overexpression of MtSWEET1b in M. truncatula roots promoted the growth of intraradical mycelium during AM symbiosis. Surprisingly, two independent Mtsweet1b mutants, which are predicted to produce truncated protein variants impaired in glucose transport, exhibited no significant defects in AM symbiosis. However, arbuscule-specific overexpression of MtSWEET1bY57A/G58D, which are considered to act in a dominant-negative manner, resulted in enhanced collapse of arbuscules. Taken together, our results reveal a (redundant) role for MtSWEET1b in the transport of glucose across the peri-arbuscular membrane to maintain arbuscules for a healthy mutually beneficial symbiosis.

Strigolactone levels in dicot roots are determined by an ancestral symbiosis-regulated clade of the PHYTOENE SYNTHASE gene family
Stauder, Ron ; Welsch, Ralf ; Camagna, Maurizio ; Kohlen, Wouter ; Balcke, Gerd U. ; Tissier, Alain ; Walter, Michael H. - \ 2018
Frontiers in Plant Science 9 (2018). - ISSN 1664-462X
Apocarotenoids - Arbuscular mycorrhiza - Carotenoids - Medicago truncatula - Solanum lycopersicum - Strigolactones - Symbiosis
Strigolactones (SLs) are apocarotenoid phytohormones synthesized from carotenoid precursors. They are produced most abundantly in roots for exudation into the rhizosphere to cope with mineral nutrient starvation through support of root symbionts. Abscisic acid (ABA) is another apocarotenoid phytohormone synthesized in roots, which is involved in responses to abiotic stress. Typically low carotenoid levels in roots raise the issue of precursor supply for the biosynthesis of these two apocarotenoids in this organ. Increased ABA levels upon abiotic stress in Poaceae roots are known to be supported by a particular isoform of phytoene synthase (PSY), catalyzing the rate-limiting step in carotenogenesis. Here we report on novel PSY3 isogenes from Medicago truncatula (MtPSY3) and Solanum lycopersicum (SlPSY3) strongly expressed exclusively upon root interaction with symbiotic arbuscular mycorrhizal (AM) fungi and moderately in response to phosphate starvation. They belong to a widespread clade of conserved PSYs restricted to dicots (dPSY3) distinct from the Poaceae-PSY3s involved in ABA formation. An ancient origin of dPSY3s and a potential co-evolution with the AM symbiosis is discussed in the context of PSY evolution. Knockdown of MtPSY3 in hairy roots of M. truncatula strongly reduced SL and AM-induced C13 α-ionol/C14 mycorradicin apocarotenoids. Inhibition of the reaction subsequent to phytoene synthesis revealed strongly elevated levels of phytoene indicating induced flux through the carotenoid pathway in roots upon mycorrhization. dPSY3 isogenes are coregulated with upstream isogenes and downstream carotenoid cleavage steps toward SLs (D27, CCD7, CCD8) suggesting a combined carotenoid/apocarotenoid pathway, which provides “just in time”-delivery of precursors for apocarotenoid formation.
RNAseq analysis of susceptible zone of the Medicago truncatula root from wild-type and Mtcre1 mutant plants 3 hours after stimulation by Rhizobium lipo-chitin oligosaccharide
Geurts, R. ; Zeijl, A.L. van - \ 2017
Wageningen University & Research
E-MTAB-3007 - Medicago truncatula - ERP105151 - PRJEB23399
RNAseq analysis of Medicago truncatula WT and Mtcre1 3h post rhizobium LCO application 4 sample with 3 biological replicates each, sequenced in both directions
Strigolactone biosynthesis requires the symbiotic GRAS-type transcription factors NSP1 and NSP2
Liu, Wei ; Kohlen, Wouter ; Lillo, Alessandra ; Camp, Rik op den; Ivanov, Sergey ; Hartog, Marijke ; Limpens, Erik ; Jamil, Muhammad ; Yang, Wei-Cai ; Hooiveld, Guido ; Charnikhova, Tatsiana ; Bouwmeester, Harro ; Bisseling, Ton ; Geurts, Rene - \ 2011
Medicago truncatula - GSE26548 - PRJNA136629
Legume GRAS-type transcription factors NSP1 and NSP2 are essential for Rhizobium Nod factor-induced nodulation. Both proteins are considered to be Nod factor response factors regulating gene expression upon symbiotic signalling. However, legume NSP1 and NSP2 can be functionally replaced by non-legume orthologs; including rice (Oryza sativa) OsNSP1 and OsNSP2. This shows that both proteins are functionally conserved in higher plants, suggesting an ancient function that was conserved during evolution. Here we show that NSP1 and NSP2 are indispensable for strigolactone biosynthesis in the legume Medicago truncatula as well as rice. Mutant nsp1-nsp2 plants hardly produce strigolactones. The lack of strigolactone biosynthesis coincides with strongly reduced DWARF27 expression in both species. Rice and Medicago represent distinct phylogenetic lineages that split ~150 million years ago. Therefore we conclude that regulation of strigolactone biosynthesis by NSP1 and NSP2 is an ancestral function conserved in higher plants. Since strigolactone biosynthesis is highly regulated by environmental conditions like phosphate starvation, NSP1 and NSP2 will be important tools in future studies on the molecular mechanisms by which environmental sensing is translated into regulation of strigolactone biosynthesis. As NSP1 and NSP2 are single copy genes in legumes, it implies that a single protein complex fulfills a dual regulatory function of different downstream targets; symbiotic and non-symbiotic, respectively.
Check title to add to marked list

Show 20 50 100 records per page

 
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.