Toubiana, D. ; Batushansky, A. ; Tzfadia, O. ; Scossa, F. ; Khan, A. ; Barak, S. ; Zamir, D. ; Fernie, A. R. ; Nikoloski, Z. ; Fait, A. .
Combined Correlation-Based Network And Mqtl Analyses Efficiently Identified Loci For Branched-Chain Amino Acid, Serine To Threonine, And Proline Metabolism In Tomato Seeds.
Plant Journal 2015,
81, 121-133.
Publisher's VersionAbstractCorrelation-based network analysis (CNA) of the metabolic profiles of seeds of a tomato introgression line mapping population revealed a clique of proteinogenic amino acids: Gly, Ile, Pro, Ser, Thr, and Val. Correlations between profiles of these amino acids exhibited a statistically significant average correlation coefficient of 0.84 as compared with an average correlation coefficient of 0.39 over the 16 119 other metabolite cliques containing six metabolites. In silico removal of cliques was used to quantify their importance in determining seminal network properties, highlighting the strong effects of the amino acid clique. Quantitative trait locus analysis revealed co-localization for the six amino acids on chromosome 2, 4 and 10. Sequence analysis identified a unique set of 10 genes on chromosome 2 only, which were associated with amino acid metabolism and specifically the metabolism of Ser-Gly and their conversion into branched-chain amino acids. Metabolite profiling of a set of sublines, with introgressions on chromosome 2, identified a significant change in the abundance of the six amino acids in comparison with M82. Expression analysis of candidate genes affecting Ser metabolism matched the observation from the metabolite data, suggesting a coordinated behavior of the level of these amino acids at the genetic level. Analysis of transcription factor binding sites in the promoter regions of the identified genes suggested combinatorial response to light and the circadian clock. Significance Statement In the current study we have effectively identified loci for branched chain amino acid, serene, glycine, threonine and proline metabolism for seeds of a tomato Introgression Line mapping population. We did so by applying a combined correlation based network approach with quantitative trait locus mapping. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.
Müller, N. A. ; Wijnen, C. L. ; Srinivasan, A. ; Ryngajllo, M. ; Ofner, I. ; Lin, T. ; Ranjan, A. ; West, D. ; Maloof, J. N. ; Sinha, N. R. ; et al. Domestication Selected For Deceleration Of The Circadian Clock In Cultivated Tomato.
Nature Genetics 2015,
48, 89-93.
Publisher's VersionAbstractThe circadian clock is a critical regulator of plant physiology and development, controlling key agricultural traits in crop plants. In addition, natural variation in circadian rhythms is important for local adaptation. However, quantitative modulation of circadian rhythms due to artificial selection has not yet been reported. Here we show that the circadian clock of cultivated tomato (Solanum lycopersicum) has slowed during domestication. Allelic variation of the tomato homolog of the Arabidopsis gene EID1 is responsible for a phase delay. Notably, the genomic region harboring EID1 shows signatures of a selective sweep. We find that the EID1 allele in cultivated tomatoes enhances plant performance specifically under long day photoperiods, suggesting that humans selected slower circadian rhythms to adapt the cultivated species to the long summer days it encountered as it was moved away from the equator. © 2016 Nature America, Inc.
Alseekh, S. ; Tohge, T. ; Wendenberg, R. ; Scossa, F. ; Omranian, N. ; Li, J. ; Kleessen, S. ; Giavalisco, P. ; Pleban, T. ; Mueller-Roeber, B. ; et al. Identification And Mode Of Inheritance Of Quantitative Trait Loci For Secondary Metabolite Abundance In Tomato.
Plant Cell 2015,
27, 485-512.
Publisher's VersionAbstractA large-scale metabolic quantitative trait loci (mQTL) analysis was performed on the well-characterized Solanum pennellii introgression lines to investigate the genomic regions associated with secondary metabolism in tomato fruit pericarp. In total, 679 mQTLs were detected across the 76 introgression lines. Heritability analyses revealed that mQTLs of secondary metabolism were less affected by environment than mQTLs of primary metabolism. Network analysis allowed us to assess the interconnectivity of primary and secondary metabolism as well as to compare and contrast their respective associations with morphological traits. Additionally, we applied a recently established real-time quantitative PCR platform to gain insight into transcriptional control mechanisms of a subset of the mQTLs, including those for hydroxycinnamates, acyl-sugar, naringenin chalcone, and a range of glycoalkaloids. Intriguingly, many of these compounds displayed a dominant-negative mode of inheritance, which is contrary to the conventional wisdom that secondary metabolite contents decreased on domestication. We additionally performed an exemplary evaluation of two candidate genes for glycolalkaloid mQTLs via the use of virus-induced gene silencing. The combined data of this study were compared with previous results on primary metabolism obtained from the same material and to other studies of natural variance of secondary metabolism. © 2015 American Society of Plant Biologists. All rights reserved.
Foucher, F. ; Hibrand-Saint Oyant, L. ; Hamama, L. ; Sakr, S. ; Baudino, S. ; Caissard, J. P. ; Smulder, J. M. S. ; Debener, T. ; De Riek, J. ; Torres, A. ; et al. Towards The Rose Genome Sequence And Its Use In Research And Breeding.
Acta Horticulturae 2015,
1064, 167-175.
Publisher's VersionAbstractRose is one of the most economically important ornamental crops worldwide. Rosa sp. can become a model for woody ornamentals. Its genome size is relatively small (560 Mb), its genetic history with ploïdy events is well documented, and rose has a short life for a woody plant. Furthermore, different tools are available, including transcriptomic tools, genetic maps and genetic transformation protocols. Rose represents an original model for studying some ornamental traits that cannot be addressed in other model plant species such as Arabidopsis. Some of these traits, such recurrent blooming, flower morphogenesis or scent production and emission, are of economic interest. Different groups involved in rose genetics and genomics gathered to form the 'Rose Genome Sequence Initiative'. Our objective is to obtain a high quality rose genome sequence of the diploid R. chinensis 'Old Blush'. One important issue is the high level of heterozygosity of roses. To tackle this issue, different strategies are proposed: production of a haploid and development a high density genetic map to anchor the genome. This genetic map will be developed from a cross between 'Old Blush' and R. wichurana. The genotype R. chinensis 'Old Blush' will be sequenced using NGS technologies. The data will be assembled and arranged using the high-density map. In order to increase ESTs and to facilitate genome annotation, we have recently produced ESTs from various tissues of 'Old Blush' under different conditions. Digital expression (RNA Seq) was obtained from the different tissues and data are available on the following web site (
https://iant.toulouse.inra.fr/plants/rosa/FATAL/). The rose genome sequence will be a great step to help identifying the molecular basis of ornamental traits and also to study genetic diversity and genome evolution in the genus Rosa and in the Rosaceae family. © 2015, International Society for Horticultural Science. All rights reserved.
Gur, A. ; Zamir, D. .
Mendelizing All Components Of A Pyramid Of Three Yield Qtl In Tomato. Front Plant Sci 2015,
6, 1096.
AbstractMolecular markers allowed breeders to mendelize quantitative trait loci (QTL) providing another demonstration that quantitative traits are governed by the same principles as single qualitative genes. This research extends the QTL analysis to two and three QTL and tests our ability to mendelize an oligogenic trait. In tomato, agricultural yield is determined by the weight of the fruits harvested per unit area and the total soluble solids (% Brix)-sugars and acids. The current study explores the segregation of multiple independent yield-related QTL that were identified and mapped using introgression lines (IL) of Solanum pennellii in cultivated processing tomato (S. lycopersicum). We screened 45 different double and triple IL-QTL combinations for agricultural yield, to identify QTL pyramids that behaved in an additive manner and were suitable substrate for mendelizing an oligogenic trait. A pyramid of three independent QTL that significantly improved Brix(∗)Yield (BXY - the soluble solids output per unit area) compared to M82 was selected. In the progenies of the tri-hybrid we bred using markers a nearly isogenic 'immortalized F2.' While the common mode of QTL-QTL interactions across the 45 IL-QTLs combinations was less than additive, the three QTLs in the selected triple-stack performed in an additive manner which made it an exceptional material for breeding. This study demonstrates that using the phenotypic effect of all 27 possible QTL-alleles combinations it is possible to make reliable predictions about the genotypes that will maximize the yield.
Ning, J. ; Moghe, G. D. ; Leong, B. ; Kim, J. ; Ofner, I. ; Wang, Z. ; Adams, C. ; Jones, D. A. ; Zamir, D. ; Last, R. L. .
A Feedback-Insensitive Isopropylmalate Synthase Affects Acylsugar Composition In Cultivated And Wild Tomato. Plant Physiol 2015,
169, 1821-35.
AbstractAcylsugars are insecticidal specialized metabolites produced in the glandular trichomes of plants in the Solanaceae family. In the tomato clade of the Solanum genus, acylsugars consist of aliphatic acids of different chain lengths esterified to sucrose, or less frequently to glucose. Through liquid chromatography-mass spectrometry screening of introgression lines, we previously identified a region of chromosome 8 in the Solanum pennellii LA0716 genome (IL8-1/8-1-1) that causes the cultivated tomato Solanum lycopersicum to shift from producing acylsucroses with abundant 3-methylbutanoic acid acyl chains derived from leucine metabolism to 2-methylpropanoic acid acyl chains derived from valine metabolism. We describe multiple lines of evidence implicating a trichome-expressed gene from this region as playing a role in this shift. S. lycopersicum M82 SlIPMS3 (Solyc08g014230) encodes a functional end product inhibition-insensitive version of the committing enzyme of leucine biosynthesis, isopropylmalate synthase, missing the carboxyl-terminal 160 amino acids. In contrast, the S. pennellii LA0716 IPMS3 allele found in IL8-1/8-1-1 encodes a nonfunctional truncated IPMS protein. M82 transformed with an SlIPMS3 RNA interference construct exhibited an acylsugar profile similar to that of IL8-1-1, whereas the expression of SlIPMS3 in IL8-1-1 partially restored the M82 acylsugar phenotype. These IPMS3 alleles are polymorphic in 14 S. pennellii accessions spread throughout the geographical range of occurrence for this species and are associated with acylsugars containing varying amounts of 2-methylpropanoic acid and 3-methylbutanoic acid acyl chains.