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Cenci, A.

Publications and source records attributed to Cenci, A..

4 recordsLinked to original sources

Painting the diversity of a world's favourite fruit: A next generation catalogue of cultivated bananas

Societal impact statementBananas are nutritious fruits of major importance in the tropics and subtropics. Characterizing their diversity is essential to ensure their conservation and use. A catalogue showcasing cultivated bananas genomic diversity was compiled and is to be used as a tool to support the classification of banana cultivars. This research revealed that cultivated banana groups are not all made of identical clones. Materials from recent collecting missions indicated that more banana diversity is expected to be found as the exploration of the banana gene pool continues. These discoveries will drive dynamic conservation strategies for banana genetic resources and will increase their use. SummaryO_LIBanana is an important food crop cultivated in many tropical and subtropical regions around the world. Due to their low fertility, banana landraces are clonally propagated. However, different factors, such as synonymy and the effects of environment, make their assignment to described sets of clones, or cultivar groups, difficult. Consequently, passport data of accessions in genebanks is often uncomplete and sometimes inaccurate. C_LIO_LIWith the recent advances in genomics, a new powerful tool was developed enabling the fine-scale characterization of bananas ancestry along chromosomes, i.e. in silico chromosome painting. We applied this method to a high-throughput genotyping data set obtained from 317 banana accessions spanning most of the known cultivar groups. This set included both genebank and new uncharacterized materials. C_LIO_LIBy comparing curated morphological assignation to the genomic patterns resulting from in silico chromosome painting, we were able to compile a catalogue referencing the chromosome painting patterns of most of the described cultivar groups. C_LIO_LIExamining the genomic patterns obtained, we discovered intra-cultivar group variability. In some cultivar groups, mitotic recombination or deletions were clonally accumulated in cultivars. In addition, we identified at least 4 cultivar groups in which cultivars likely resulting from distinct sexual events co-existed, notably Pisang Awak in which 5 distinct genomic patterns of two ploidy levels were identified. New patterns were also discovered in the newest materials of the set, showing that a wider diversity of clones still exist on farm. C_LI

genomics↗

Phylogenetic analyses for orthogroup-based classification of GDSL-type esterase/lipase (GELP) family in angiosperms

GDSL-type esterase/lipase (GELP) enzymes have multiple functions in plants, spanning from developmental processes to the response to biotic and abiotic stresses. Genes encoding GELP belong to a large gene family with several tens to more than hundred members per angiosperm species. Here, we applied iterative phylogenetic analyses to identify 10 main clusters subdivided into 44 expert-curated reference orthogroups (OGs) using three monocot and five dicot genomes. Our results show that some GELP OGs expanded while others were maintained as single copy genes. This semi-automatic approach proves to be effective to characterize large gene families and provides a solid classification framework for the GELP members in angiosperms. The orthogroup-based reference will be useful to perform comparative studies, infer gene functions and better understand the evolutionary history of this gene family.

genomics↗

Unraveling the complex story of intergenomic recombination in ABB allotriploid bananas

Background and AimsBananas (Musa spp.) are a major staple food for hundreds of millions of people in developing countries. The cultivated varieties are seedless and parthenocarpic clones of which the ancestral origin remains to be clarified. The most important cultivars are triploids with an AAA, AAB, or ABB genome constitution, with A and B genomes provided by M. acuminata and M. balbisiana, respectively. Previous studies suggested that inter-genome recombinations were relatively common in banana cultivars and that triploids were more likely to have passed through an intermediate hybrid. In this study, we investigated the chromosome structure within the ABB group, composed of starchy cooking bananas that play an important role in food security.\n\nMethodsUsing SNP markers called from RAD-Seq data, we studied the chromosome structure of 36 ABB genotypes spanning defined taxonomic subgroups. To complement our understanding, we search for similar events within nine AB hybrid genotypes.\n\nKey ResultsRecurrent Homoeologous Exchanges (HEs), i.e. chromatin exchanges between A and B subgenomes were unraveled with at least 9 founding events at the origin of the ABB bananas prior to the clonal diversification. The discovery of this nine founding events allows discussing the possible routes that led to the creation of the different subgroups and formulate new hypotheses. Based on our observations, we suggest different routes that gave rise to the current diversity in the ABB cultivars. Routes involving primary AB hybrids, routes leading to shared HEs and routes leading to a B excess ratio. Genetic fluxes took place between M. acuminata and M. balbisiana, particularly in India, where these unbalanced AB hybrids and ABB allotriploid originated and where cultivated M. balbisiana are abundant.\n\nConclusionsThe result of this study clarifies the classification of ABB cultivars and leading possibly to the revision of the classification of this subgroup. This is an important step to unravel the origin of polyploid bananas, and contributes to possible scenarios on the origin. ABB bananas are hypothesized to be more drought tolerant. Knowing the origin of our current cultivars and so their potential parents will help breeders to make the right choices for future crosses. The M. balbisiana genome is a good source to create new cultivars able to answer the numerous challenges of banana breeding.

genomics↗

Three new genome assemblies support a rapid radiation in Musa acuminata (wild banana)

Edible bananas result from interspecific hybridization between Musa acuminata and Musa balbisiana, as well as among subspecies in M. acuminata. Four particular M. acuminata subspecies have been proposed as the main contributors of edible bananas, all of which radiated in a short period of time in southeastern Asia. Clarifying the evolution of these lineages at a whole-genome scale is therefore an important step toward understanding the domestication and diversification of this crop. This study reports the de novo genome assembly and gene annotation of a representative genotype from three different subspecies of M. acuminata. These data are combined with the previously published genome of the fourth subspecies to investigate phylogenetic relationships and genome evolution. Analyses of shared and unique gene families reveal that the four subspecies are quite homogenous, with a core genome representing at least 50% of all genes and very few M. acuminata species-specific gene families. Multiple alignments indicate high sequence identity between homologous single copy-genes, supporting the close relationships of these lineages. Interestingly, phylogenomic analyses demonstrate high levels of gene tree discordance, due to both incomplete lineage sorting and introgression. This pattern suggests rapid radiation within Musa acuminata subspecies that occurred after the divergence with M. balbisiana. Introgression between M. a. ssp. malaccensis and M. a. ssp. burmannica was detected across a substantial portion of the genome, though multiple approaches to resolve the subspecies tree converged on the same topology. To support future evolutionary and functional analyses, we introduce the PanMusa database, which enables researchers to exploration of individual gene families and trees.

evolutionary biology↗