Variation in rDNA locus number and position among legume species and detection of 2 linked rDNA loci in the model Medicago truncatula by FISH

Within Fabaceae, legume species have a variable genome size, chromosome number, and ploidy level. The genome distribution of ribosomal genes, easily detectable by fluorescent in situ hybridization (FISH), is a good tool for anchoring physical and genetic comparative maps. The organisation of 45S rDNA and 5S loci was analysed by FISH in the 4 closely related species: Pisum sativum, Medicago truncatula, Medicago sativa (2 diploid taxa), and Lathyrus sativus. The 2 types of rDNA arrays displayed interspecific variation in locus number and location, but little intraspecific variation was detected. In the model legume, M. truncatula, the presence of 2 adjacent 45S rDNA loci was demonstrated, and the location of the rDNA loci was independent of the general evolution of the genome DNA. The different parameters relative to clustering of the rDNA loci in specific chromosome regions and the possible basis of rDNA instability are discussed.Key words: ribosomal genes, FISH, Medicago species, Pisum sativum, Lathyrus sativus, rDNA mobility.

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Characterisation of Medicago truncatula CLE34 and CLE35 in nodulation control

10.1101/2020.07.31.231605 ◽

2020 ◽

Author(s):

Celine Mens ◽

April H. Hastwell ◽

Huanan Su ◽

Peter M. Gresshoff ◽

Ulrike Mathesius ◽

...

Keyword(s):

Pisum Sativum ◽

Medicago Truncatula ◽

Sequence Homology ◽

Dependent Manner ◽

Legume Species ◽

Mature Peptide ◽

Cle Peptides ◽

Autoregulation Of Nodulation ◽

Cle Peptide ◽

Distinct Role

AbstractLegume plants form a symbiosis with N2-fixing soil rhizobia, resulting in new root organs called nodules that enable N2-fixation. Nodulation is a costly process that is tightly regulated by the host through Autoregulation of Nodulation (AON) and nitrate-dependent regulation of nodulation. Both pathways require legume-specific CLAVATA/ESR-related (CLE) peptides. Nitrogen-induced nodulation-suppressing CLE peptides have not previously been characterised in Medicago truncatula, with only rhizobia-induced MtCLE12 and MtCLE13 identified. Here, we report on novel peptides MtCLE34 and MtCLE35 in nodulation control pathways. The nodulation-suppressing CLE peptides of five legume species were classified into three clades based on sequence homology and phylogeny. This approached identified MtCLE34 and MtCLE35 and four new CLE peptide orthologues of Pisum sativum. Whereas MtCLE12 and MtCLE13 are induced by rhizobia, MtCLE34 and MtCLE35 respond to both rhizobia and nitrate. MtCLE34 was identified as a pseudogene lacking a functional CLE-domain. Overexpression of MtCLE12, MtCLE13 and MtCLE35 inhibits nodulation. Together, our findings indicate that MtCLE12 and MtCLE13 have a distinct role in AON, while MtCLE35 regulates nodule numbers in a rhizobia- and nitrate-dependent manner. MtCLE34 likely had a similar role to MtCLE35 but its function was lost due to a nonsense mutation resulting in the loss of the mature peptide.

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Zinc finger CCHC-type protein related with seed size in model legume species Medicago truncatula

Biotechnology & Biotechnological Equipment ◽

10.1080/13102818.2019.1568914 ◽

2019 ◽

Vol 33 (1) ◽

pp. 278-285 ◽

Cited By ~ 2

Author(s):

Mariana Radkova ◽

Miglena Revalska ◽

Daniela Kertikova ◽

Anelia Iantcheva

Keyword(s):

Zinc Finger ◽

Medicago Truncatula ◽

Seed Size ◽

Legume Species ◽

Model Legume ◽

Type Protein

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Detection of QTLs for flowering date in three mapping populations of the model legume species Medicago truncatula

Theoretical and Applied Genetics ◽

10.1007/s00122-008-0805-4 ◽

2008 ◽

Vol 117 (4) ◽

pp. 609-620 ◽

Cited By ~ 52

Author(s):

Jean-Baptiste Pierre ◽

Thierry Huguet ◽

Philippe Barre ◽

Christian Huyghe ◽

Bernadette Julier

Keyword(s):

Medicago Truncatula ◽

Legume Species ◽

Model Legume ◽

Flowering Date ◽

Mapping Populations

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LegumeDB1 bioinformatics resource: comparative genomic analysis and novel cross-genera marker identification in lupin and pasture legume species

Genome ◽

10.1139/g06-009 ◽

2006 ◽

Vol 49 (6) ◽

pp. 689-699 ◽

Cited By ~ 6

Author(s):

P Moolhuijzen ◽

M Cakir ◽

A Hunter ◽

D Schibeci ◽

A Macgregor ◽

...

Keyword(s):

Medicago Truncatula ◽

Expressed Sequence Tags ◽

Lotus Japonicus ◽

Comparative Genomic ◽

Legume Species ◽

Model Legume ◽

Bioinformatics Resource ◽

Expressed Sequence ◽

Simple Sequence ◽

Pasture Legume

The identification of markers in legume pasture crops, which can be associated with traits such as protein and lipid production, disease resistance, and reduced pod shattering, is generally accepted as an important strategy for improving the agronomic performance of these crops. It has been demonstrated that many quantitative trait loci (QTLs) identified in one species can be found in other plant species. Detailed legume comparative genomic analyses can characterize the genome organization between model legume species (e.g., Medicago truncatula, Lotus japonicus) and economically important crops such as soybean (Glycine max), pea (Pisum sativum), chickpea (Cicer arietinum), and lupin (Lupinus angustifolius), thereby identifying candidate gene markers that can be used to track QTLs in lupin and pasture legume breeding. LegumeDB is a Web-based bioinformatics resource for legume researchers. LegumeDB analysis of Medicago truncatula expressed sequence tags (ESTs) has identified novel simple sequence repeat (SSR) markers (16 tested), some of which have been putatively linked to symbiosome membrane proteins in root nodules and cell-wall proteins important in plant-pathogen defence mechanisms. These novel markers by preliminary PCR assays have been detected in Medicago truncatula and detected in at least one other legume species, Lotus japonicus, Glycine max, Cicer arietinum, and (or) Lupinus angustifolius (15/16 tested). Ongoing research has validated some of these markers to map them in a range of legume species that can then be used to compile composite genetic and physical maps. In this paper, we outline the features and capabilities of LegumeDB as an interactive application that provides legume genetic and physical comparative maps, and the efficient feature identification and annotation of the vast tracks of model legume sequences for convenient data integration and visualization. LegumeDB has been used to identify potential novel cross-genera polymorphic legume markers that map to agronomic traits, supporting the accelerated identification of molecular genetic factors underpinning important agronomic attributes in lupin.Key words: legumes, comparative genomics, bioinformatics, expressed sequence tags (ESTs), simple sequence repeats (SSRs).

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Fabaceae leaf morphogenetic evolution: the leaf-lamina architectural variation in the Fabaceae flora of Indian Western Ghats, compared with that genetically characterized in the Fabaceae model species Pisum sativum and Medicago truncatula

Proceedings of the Indian National Science Academy ◽

10.1007/s43538-021-00037-2 ◽

2021 ◽

Author(s):

Sushil Kumar ◽

Vishakha Sharma ◽

Renu Kumari

Keyword(s):

Pisum Sativum ◽

Medicago Truncatula ◽

Western Ghats ◽

Leaf Lamina ◽

Model Species

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An improved genome release (version Mt4.0) for the model legume Medicago truncatula

BMC Genomics ◽

10.1186/1471-2164-15-312 ◽

2014 ◽

Vol 15 (1) ◽

pp. 312 ◽

Cited By ~ 191

Author(s):

Haibao Tang ◽

Vivek Krishnakumar ◽

Shelby Bidwell ◽

Benjamin Rosen ◽

Agnes Chan ◽

...

Keyword(s):

Medicago Truncatula ◽

Model Legume

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Guidelines for Genetic Nomenclature and Community Governance for the Model Legume Medicago truncatula

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2001.14.12.1364 ◽

2001 ◽

Vol 14 (12) ◽

pp. 1364-1367 ◽

Cited By ~ 14

Author(s):

Kathryn A. VandenBosch ◽

Julia Frugoli

Keyword(s):

Medicago Truncatula ◽

Rapid Growth ◽

Model System ◽

Gene Nomenclature ◽

Community Governance ◽

Model Legume ◽

The Past ◽

Genetic Nomenclature ◽

International Collaborations

At the 2nd Medicago meeting (a satellite of the 1999 IS-MPMI meeting in Amsterdam), investigators perceived a need for standardization of genetic nomenclature in Medicago truncatula, due to the rapid growth of research on this species in the past few years. Establishment of such standards grew out of discussions begun at this meeting and continued electronically throughout the M. truncatula community. The proposed standards presented here are the consensus results of those discussions. In addition to standards for gene nomenclature, a method for community governance and a website for cataloging gene names and submitting new ones are presented. The purpose of implementing these guidelines is to help maintain consistency in the literature, to avoid redundancy, to contribute to the accuracy of databases, and, in general, to aid the international collaborations that have made M. truncatula a model system for legume biology.

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Structure and antimicrobial activity of NCR169, a nodule-specific cysteine-rich peptide of Medicago truncatula

Scientific Reports ◽

10.1038/s41598-021-89485-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Noriyoshi Isozumi ◽

Yuya Masubuchi ◽

Tomohiro Imamura ◽

Masashi Mori ◽

Hironori Koga ◽

...

Keyword(s):

Antimicrobial Activity ◽

Medicago Truncatula ◽

Mechanism Of Action ◽

Disulfide Bonds ◽

Sinorhizobium Meliloti ◽

Bound State ◽

Disulfide Linkage ◽

Model Legume ◽

Nmr Structures ◽

And Function

AbstractA model legume, Medicago truncatula, has over 600 nodule-specific cysteine-rich (NCR) peptides required for symbiosis with rhizobia. Among them, NCR169, an essential factor for establishing symbiosis, has four cysteine residues that are indispensable for its function. However, knowledge of NCR169 structure and mechanism of action is still lacking. In this study, we solved two NMR structures of NCR169 caused by different disulfide linkage patterns. We show that both structures have a consensus C-terminal β-sheet attached to an extended N-terminal region with dissimilar features; one moves widely, whereas the other is relatively stapled. We further revealed that the disulfide bonds of NCR169 contribute to its structural stability and solubility. Regarding the function, one of the NCR169 oxidized forms could bind to negatively charged bacterial phospholipids. Furthermore, the positively charged lysine-rich region of NCR169 may be responsible for its antimicrobial activity against Escherichia coli and Sinorhizobium meliloti. This active region was disordered even in the phospholipid bound state, suggesting that the disordered conformation of this region is key to its function. Morphological observations suggested the mechanism of action of NCR169 on bacteria. The present study on NCR169 provides new insights into the structure and function of NCR peptides.

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