Deciphering the Theobroma cacao self-incompatibility system: from genomics to diagnostic markers for self-compatibility

Autor: Karina Peres Gramacho, Ronan Rivallan, Benoit Mermaz, Marie Claire Eyango, Géraldine Mastin, Thierry Legavre, Uilson Vanderlei Lopes, Ives Bruno Efombagn Mousseni, Kelly Colonges, Jean-Luc Verdeil, Claire Lanaud, N. C. Cryer, Olivier Fouet, Herman Ebai Ebaiarrey, Xavier Argout, Rey Gaston Loor Solorzano, Gabor Gyapay, Marcos Ramos da Silva, Michel Boccara, Didier Clément, Christine Sanier, Olivier Sounigo
Rok vydání: 2017
Předmět:
0106 biological sciences
0301 basic medicine
Identification
Candidate gene
Linkage disequilibrium
Physiology
Genetic Linkage
Plant Science
01 natural sciences
self-incompatibility
F30 - Génétique et amélioration des plantes
Immunologie
Genotype
Autocompatibilité
Expression des gènes
Marqueur génétique
Genetics
F63 - Physiologie végétale - Reproduction
food and beverages
Chromosome Mapping
Self-Incompatibility in Flowering Plants
Research Papers
Crop Molecular Genetics
Génotype
Locus
Physiologie de la reproduction
Locus (genetics)
Genomics
Biology
génomique
Candidate genes
03 medical and health sciences
immunolocalization
Theobroma cacao
Allele
Gene
Genetic association
Cacao
030104 developmental biology
Gène
diagnostic markers
fine mapping
Carte génétique
gene expression
Autostérilité
010606 plant biology & botany
Genome-Wide Association Study
Zdroj: Journal of Experimental Botany
ISSN: 1460-2431
Popis: Two different mechanisms controlling the Theobroma cacao self-incompatibility system were identified at two separate loci together with candidate genes differentially expressed between self-compatible/incompatible reactions, and diagnostic markers predicting self-compatible varieties were produced.
Cocoa self-compatibility is an important yield factor and has been described as being controlled by a late gameto-sporophytic system expressed only at the level of the embryo sac. It results in gametic non-fusion and involves several loci. In this work, we identified two loci, located on chromosomes 1 and 4 (CH1 and CH4), involved in cocoa self-incompatibility by two different processes. Both loci are responsible for gametic selection, but only one (the CH4 locus) is involved in the main fruit drop. The CH1 locus acts prior to the gamete fusion step and independently of the CH4 locus. Using fine-mapping and genome-wide association studies, we focused analyses on restricted regions and identified candidate genes. Some of them showed a differential expression between incompatible and compatible reactions. Immunolocalization experiments provided evidence of CH1 candidate genes expressed in ovule and style tissues. Highly polymorphic simple sequence repeat (SSR) diagnostic markers were designed in the CH4 region that had been identified by fine-mapping. They are characterized by a strong linkage disequilibrium with incompatibility alleles, thus allowing the development of efficient diagnostic markers predicting self-compatibility and fruit setting according to the presence of specific alleles or genotypes. SSR alleles specific to self-compatible Amelonado and Criollo varieties were also identified, thus allowing screening for self-compatible plants in cocoa populations.
Databáze: OpenAIRE
Externí odkaz: