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Estanislao Burgos Maria Belen De Luca Isidore Diouf Luis A. de Haro Elise Albert Christopher Sauvage Zhao J. Tao Luisa Bermudez Ramon Asís Adriano N. Nesi Michel Matringe Claire Bréhélin Thomas Guiraud Carine Ferrand Isabelle Atienza Joana Jorly Jean P. Mauxion Pierre Baldet Alisdair R. Fernie Leandro Quadrana Christophe Rothan Mathilde Causse Fernando Carrari 《The Plant journal : for cell and molecular biology》2021,105(4):907-923
574.
José Blanca Javier Montero-Pau Christopher Sauvage Guillaume Bauchet Eudald Illa María José Díez David Francis Mathilde Causse Esther van der Knaap Joaquín Ca?izares 《BMC genomics》2015,16(1)
Background
Domestication modifies the genomic variation of species. Quantifying this variation provides insights into the domestication process, facilitates the management of resources used by breeders and germplasm centers, and enables the design of experiments to associate traits with genes. We described and analyzed the genetic diversity of 1,008 tomato accessions including Solanum lycopersicum var. lycopersicum (SLL), S. lycopersicum var. cerasiforme (SLC), and S. pimpinellifolium (SP) that were genotyped using 7,720 SNPs. Additionally, we explored the allelic frequency of six loci affecting fruit weight and shape to infer patterns of selection.Results
Our results revealed a pattern of variation that strongly supported a two-step domestication process, occasional hybridization in the wild, and differentiation through human selection. These interpretations were consistent with the observed allele frequencies for the six loci affecting fruit weight and shape. Fruit weight was strongly selected in SLC in the Andean region of Ecuador and Northern Peru prior to the domestication of tomato in Mesoamerica. Alleles affecting fruit shape were differentially selected among SLL genetic subgroups. Our results also clarified the biological status of SLC. True SLC was phylogenetically positioned between SP and SLL and its fruit morphology was diverse. SLC and “cherry tomato” are not synonymous terms. The morphologically-based term “cherry tomato” included some SLC, contemporary varieties, as well as many admixtures between SP and SLL. Contemporary SLL showed a moderate increase in nucleotide diversity, when compared with vintage groups.Conclusions
This study presents a broad and detailed representation of the genomic variation in tomato. Tomato domestication seems to have followed a two step-process; a first domestication in South America and a second step in Mesoamerica. The distribution of fruit weight and shape alleles supports that domestication of SLC occurred in the Andean region. Our results also clarify the biological status of SLC as true phylogenetic group within tomato. We detect Ecuadorian and Peruvian accessions that may represent a pool of unexplored variation that could be of interest for crop improvement.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1444-1) contains supplementary material, which is available to authorized users. 相似文献575.
Emadeldin H.E. Konozy Mathilde Causse Mireille Faurobert 《Saudi Journal of Biological Sciences》2012,19(3):277-283
Excessive softening is the main factor limiting fruit shelf life and storage. It is generally acceptable now that softening of fruit which occurs during the ripening is due to synergistic actions of several enzymes on cell wall polysaccharides. As a subject for this study, we have assayed some glycosidase activities using three tomato species (Lycopersicon esculentum) contrasted for their texture phenotypes; the cherry tomato line Cervil (Solanum lycopersicum var. cerasiforme), a common taste tomato line Levovil (S. lycopersicum Mill.) and VilB a modern line, large, firmer and with good storage capability. Four glycosidase activities namely α-galactosidase, β-galactosidase, β-mannosidase and β-glucosidase were extracted from tomato’s cell wall of the three species. Cell wall protein from fruits pericarp was extracted and compared among the three cultivars at the following stages; 14 days post anthesis (14DPA) fruit; 21 days post anthesis (21DPA), turning (breaker), red and over ripe. When glycolytic activities were also compared among these cultivars at the precited development stages, gross variations were noticed from stage to stage and also from species to species in accordance with the fruit firmness status. Interestingly, VilB cultivar, the firmer among the other two, though possessed the highest total protein content, exhibited the lowest enzymatic activities. Taken together, these results may therefore allow us to conclude that studies of glycolytic activities in a single tomato cultivar cannot be generalized to all species. On the other hand, relating fruit development to glycosidase activities should logically be coupled to these enzymes from cell wall compartment. 相似文献
576.
The number of stem cells contributing to hematopoiesis has been a matter of debate. Many studies use retroviral tagging of stem cells to measure clonal contribution. Here we argue that methodological factors can impact such clonal analyses. Whereas early studies had low resolution, leading to underestimation, recent methods may result in an overestimation of stem-cell counts. We discuss how restriction enzyme choice, PCR bias, high-throughput sequencing depth and tagging method could affect the conclusions of clonal studies. 相似文献
577.
Naomi L. Forrester Mathilde Guerbois Robert L. Seymour Heidi Spratt Scott C. Weaver 《PLoS pathogens》2012,8(9)
RNA viruses typically occur in genetically diverse populations due to their error-prone genome replication. Genetic diversity is thought to be important in allowing RNA viruses to explore sequence space, facilitating adaptation to changing environments and hosts. Some arboviruses that infect both a mosquito vector and a mammalian host are known to experience population bottlenecks in their vectors, which may constrain their genetic diversity and could potentially lead to extinction events via Muller''s ratchet. To examine this potential challenge of bottlenecks for arbovirus perpetuation, we studied Venezuelan equine encephalitis virus (VEEV) enzootic subtype IE and its natural vector Culex (Melanoconion) taeniopus, as an example of a virus-vector interaction with a long evolutionary history. Using a mixture of marked VEEV clones to infect C. taeniopus and real-time RT-PCR to track these clones during mosquito infection and dissemination, we observed severe bottleneck events that resulted in a significant drop in the number of clones present. At higher initial doses, the midgut was readily infected and there was a severe bottleneck at the midgut escape. Following a lower initial dose, the major bottleneck occurred at initial midgut infection. A second, less severe bottleneck was identified at the salivary gland infection stage following intrathoracic inoculation. Our results suggest that VEEV consistently encounters bottlenecks during infection, dissemination and transmission by its natural enzootic vector. The potential impacts of these bottlenecks on viral fitness and transmission, and the viral mechanisms that prevent genetic drift leading to extinction, deserve further study. 相似文献
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579.
Richard Le Boucher Mathilde Dupont-Nivet Marc Vandeputte Thierry Kerne?s Lionel Goardon Laurent Labbé Béatrice Chatain Marie Josée Bothaire Laurence Larroquet Fran?oise Médale Edwige Quillet 《PloS one》2012,7(9)
Genetic adaptation to dietary environments is a key process in the evolution of natural populations and is of great interest in animal breeding. In fish farming, the use of fish meal and fish oil has been widely challenged, leading to the rapidly increasing use of plant-based products in feed. However, high substitution rates impair fish health and growth in carnivorous species. We demonstrated that survival rate, mean body weight and biomass can be improved in rainbow trout (Oncorhynchus mykiss) after a single generation of selection for the ability to adapt to a totally plant-based diet (15.1%, 35.3% and 54.4%, respectively). Individual variability in the ability to adapt to major diet changes can be effectively used to promote fish welfare and a more sustainable aquaculture. 相似文献
580.
Transplanted mesoangioblasts require macrophage IL-10 for survival in a mouse model of muscle injury
Bosurgi L Corna G Vezzoli M Touvier T Cossu G Manfredi AA Brunelli S Rovere-Querini P 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(12):6267-6277
The aim of this study was to verify whether macrophages influence the fate of transplanted mesoangioblasts--vessel-associated myogenic precursors--in a model of sterile toxin-induced skeletal muscle injury. We have observed that in the absence of macrophages, transplanted mesoangioblasts do not yield novel fibers. Macrophages retrieved from skeletal muscles at various times after injury display features that resemble those of immunoregulatory macrophages. Indeed, they secrete IL-10 and express CD206 and CD163 membrane receptors and high amounts of arginase I. We have reconstituted the muscle-associated macrophage population by injecting polarized macrophages before mesoangioblast injection: alternatively activated, immunoregulatory macrophages only support mesoangioblast survival and function. This action depends on the secretion of IL-10 in the tissue. Our results reveal an unanticipated role for tissue macrophages in mesoangioblast function. Consequently, the treatment of muscle disorders with mesoangioblasts should take into consideration coexisting inflammatory pathways, whose activation may prove crucial for its success. 相似文献