A gene-based map of the Nod factor-independent Aeschynomene evenia sheds new light on the evolution of nodulation and legume genomes.
Aeschynomene evenia has emerged as a new model legume for the deciphering of the molecular mechanisms of an alternative symbiotic process that is independent of the Nod factors. Whereas most of the research on nitrogen-fixing symbiosis, legume genetics and genomics has so far focused on Galegoid and Phaseolid legumes, A. evenia falls in the more basal and understudied Dalbergioid clade along with peanut (Arachis hypogaea). To provide insights into the symbiotic genes content and the structure of the A. evenia genome, we established a gene-based genetic map for this species. Firstly, an RNAseq analysis was performed on the two parental lines selected to generate a F2 mapping population. The transcriptomic data were used to develop molecular markers and they allowed the identification of most symbiotic genes. The resulting map comprised 364 markers arranged in 10 linkage groups (2n = 20). A comparative analysis with the sequenced genomes of Arachis duranensis and A. ipaensis, the diploid ancestors of peanut, indicated blocks of conserved macrosynteny. Altogether, these results provided important clues regarding the evolution of symbiotic genes in a Nod factor-independent context. They provide a basis for a genome sequencing project and pave the way for forward genetic analysis of symbiosis in A. evenia.
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Clémence
C
Chaintreuil
CIRAD, UMR AGAP, Campus de Lavalette, F-34398 Montpellier, France.
Ronan
R
Rivallan
University of Brasília, Institute of Biological Sciences, Campus Darcy Ribeiro, 70910-900 Brasília, DF, Brazil.
David J
DJ
Bertioli
INRA, Plateforme GenoToul Bioinfo, UR 875, INRA Auzeville, F-31326 Castanet-Tolosan, France.
Christophe
C
Klopp
INRA, UMR441 LIPM, INRA Auzeville, F-31326 Castanet-Tolosan, France.
Jérôme
J
Gouzy
CIRAD, UMR AGAP, Campus de Lavalette, F-34398 Montpellier, France.
Brigitte
B
Courtois
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France INRA, Plateforme GenoToul Bioinfo, UR 875, INRA Auzeville, F-31326 Castanet-Tolosan, France.
Philippe
P
Leleux
CIRAD, UMR AGAP, Campus de Lavalette, F-34398 Montpellier, France.
Guillaume
G
Martin
CIRAD, UMR AGAP, Campus de Lavalette, F-34398 Montpellier, France.
Jean-François
JF
Rami
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Djamel
D
Gully
MGX-Montpellier GenomiX, Institut de Génomique Fonctionnelle, F-34094 Montpellier, France.
Hugues
H
Parrinello
MGX-Montpellier GenomiX, Institut de Génomique Fonctionnelle, F-34094 Montpellier, France.
Dany
D
Séverac
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France IRD, Centre IRD de Montpellier France Sud, F-34394 Montpellier, France.
Delphine
D
Patrel
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Joël
J
Fardoux
IRD, Centre IRD de Montpellier France Sud, F-34394 Montpellier, France.
William
W
Ribière
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Marc
M
Boursot
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Fabienne
F
Cartieaux
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Pierre
P
Czernic
Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France.
Pascal
P
Ratet
CIRAD, UMR AGAP, Campus de Lavalette, F-34398 Montpellier, France.
Pierre
P
Mournet
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France.
Eric
E
Giraud
IRD, UMR LSTM, Campus International de Baillarguet, F-34398 Montpellier, France jean-francois.arrighi@ird.fr.
Jean-François
JF
Arrighi
D019143:Evolution, Molecular; D007887:Fabaceae / Q000235:genetics* / Q000382:microbiology / Q000502:physiology; D017343:Genes, Plant; D008040:Genetic Linkage; D018745:Genome, Plant; D055170:Plant Root Nodulation / Q000235:genetics*; D011110:Polymorphism, Genetic; D013559:Symbiosis / Q000235:genetics; D059467:Transcriptome
Aeschynomene evenia; comparative genomics; genetic map; legume; symbiosis