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1.
Chromosoma ; 132(2): 105-115, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36964786

RESUMO

Minichromosomes are small, sometimes circular, rearranged chromosomes consisting of one centromere and short chromosomal arms formed by treatments that break DNA, including plant transformation. Minichromosomes have the potential to serve as vectors to quickly move valuable genes across a wide range of germplasm, including into adapted crop varieties. To realize this potential, minichromosomes must be reliably generated, easily manipulated, and stably inherited. Here we show a reliable method for minichromosome formation in haploids resulting from CENH3-mediated genome elimination, a process that generates genome instability and karyotypic novelty specifically on one parental genome. First, we identified 2 out of 260 haploids, each containing a single-copy minichromosome originating from centromeric regions of chromosomes 1 and 3, respectively. The chromosome 1 minichromosome we characterized did not pair at meiosis but displayed consistent transmission over nine selfing generations. Next, we demonstrated that CENH3-based haploid induction can produce minichromosomes in a targeted manner. Haploid inducers carrying a selectable pericentromeric marker were used to isolate additional chromosome-specific minichromosomes, which occurred in 3 out of 163 haploids. Our findings document the formation of heritable, rearranged chromosomes, and we provide a method for convenient minichromosome production.


Assuntos
Arabidopsis , Haploidia , Arabidopsis/genética , Centrômero/genética , Plantas/genética , Genoma
2.
New Phytol ; 239(4): 1368-1383, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37306070

RESUMO

Inorganic phosphate (Pi) is a necessary macronutrient for basic biological processes. Plants modulate their root system architecture (RSA) and cellular processes to adapt to Pi deprivation albeit with a growth penalty. Excess application of Pi fertilizer, on the contrary, leads to eutrophication and has a negative environmental impact. We compared RSA, root hair elongation, acid phosphatase activity, metal ion accumulation, and brassinosteroid hormone levels of Solanum lycopersicum (tomato) and Solanum pennellii, which is a wild relative of tomato, under Pi sufficiency and deficiency conditions to understand the molecular mechanism of Pi deprivation response in tomato. We showed that S. pennellii is partially insensitive to phosphate deprivation. Furthermore, it mounts a constitutive response under phosphate sufficiency. We demonstrate that activated brassinosteroid signaling through a tomato BZR1 ortholog gives rise to the same constitutive phosphate deficiency response, which is dependent on zinc overaccumulation. Collectively, these results reveal an additional strategy by which plants can adapt to phosphate starvation.


Assuntos
Fosfatos , Solanum lycopersicum , Fosfatos/metabolismo , Brassinosteroides/farmacologia , Zinco , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismo
4.
PLoS Genet ; 15(9): e1008367, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31513571

RESUMO

Plant developmental dynamics can be heritable, genetically correlated with fitness and yield, and undergo selection. Therefore, characterizing the mechanistic connections between the genetic architecture governing plant development and the resulting ontogenetic dynamics of plants in field settings is critically important for agricultural production and evolutionary ecology. We use hierarchical Bayesian Function-Valued Trait (FVT) models to estimate Brassica rapa growth curves throughout ontogeny, across two treatments, and in two growing seasons. We find genetic variation for plasticity of growth rates and final sizes, but not the inflection point (transition from accelerating to decelerating growth) of growth curves. There are trade-offs between growth rate and duration, indicating that selection for maximum yields at early harvest dates may come at the expense of late harvest yields and vice versa. We generate eigengene modules and determine which are co-expressed with FVT traits using a Weighted Gene Co-expression Analysis. Independently, we seed a Mutual Rank co-expression network model with FVT traits to identify specific genes and gene networks related to FVT. GO-analyses of eigengene modules indicate roles for actin/cytoskeletal genes, herbivore resistance/wounding responses, and cell division, while MR networks demonstrate a close association between metabolic regulation and plant growth. We determine that combining FVT Quantitative Trait Loci (QTL) and MR genes/WGCNA eigengene expression profiles better characterizes phenotypic variation than any single data type (i.e. QTL, gene, or eigengene alone). Our network analysis allows us to employ a targeted eQTL analysis, which we use to identify regulatory hotspots for FVT. We examine cis vs. trans eQTL that mechanistically link FVT QTL with structural trait variation. Colocalization of FVT, gene, and eigengene eQTL provide strong evidence for candidate genes influencing plant height. The study is the first to explore eQTL for FVT, and specifically do so in agroecologically relevant field settings.


Assuntos
Brassica rapa/genética , Brassica rapa/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Teorema de Bayes , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/fisiologia , Redes Reguladoras de Genes/genética , Genômica/métodos , Genótipo , Fenótipo , Locos de Características Quantitativas/genética , Transcriptoma/genética
5.
Plant J ; 103(2): 781-800, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32282967

RESUMO

Terpenoid metabolism plays vital roles in stress defense and the environmental adaptation of monocot crops. Here, we describe the identification of the terpene synthase (TPS) gene family of the panicoid food and bioenergy model crop foxtail millet (Setaria italica). The diploid S. italica genome contains 32 TPS genes, 17 of which were biochemically characterized in this study. Unlike other thus far investigated grasses, S. italica contains TPSs producing all three ent-, (+)- and syn-copalyl pyrophosphate stereoisomers that naturally occur as central building blocks in the biosynthesis of distinct monocot diterpenoids. Conversion of these intermediates by the promiscuous TPS SiTPS8 yielded different diterpenoid scaffolds. Additionally, a cytochrome P450 monooxygenase (CYP99A17), which genomically clustered with SiTPS8, catalyzes the C19 hydroxylation of SiTPS8 products to generate the corresponding diterpene alcohols. The presence of syntenic orthologs to about 19% of the S. italica TPSs in related grasses supports a common ancestry of selected pathway branches. Among the identified enzyme products, abietadien-19-ol, syn-pimara-7,15-dien-19-ol and germacrene-d-4-ol were detectable in planta, and gene expression analysis of the biosynthetic TPSs showed distinct and, albeit moderately, inducible expression patterns in response to biotic and abiotic stress. In vitro growth-inhibiting activity of abietadien-19-ol and syn-pimara-7,15-dien-19-ol against Fusarium verticillioides and Fusarium subglutinans may indicate pathogen defensive functions, whereas the low antifungal efficacy of tested sesquiterpenoids supports other bioactivities. Together, these findings expand the known chemical space of monocot terpenoid metabolism to enable further investigations of terpenoid-mediated stress resilience in these agriculturally important species.


Assuntos
Alquil e Aril Transferases/genética , Genes de Plantas/genética , Proteínas de Plantas/genética , Setaria (Planta)/genética , Genoma de Planta/genética , Família Multigênica/genética , Setaria (Planta)/enzimologia , Terpenos/metabolismo
6.
New Phytol ; 232(2): 868-879, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34318484

RESUMO

Effective insect pollination requires appropriate responses to internal and external environmental cues in both the plant and the pollinator. Helianthus annuus, a highly outcrossing species, is marked for its uniform eastward orientation of mature pseudanthia, or capitula. Here we investigate how this orientation affects floral microclimate and the consequent effects on plant and pollinator interactions and reproductive fitness. We artificially manipulated sunflower capitulum orientation and temperature in both field and controlled conditions and assessed flower physiology, pollinator visits, seed traits and siring success. East-facing capitula were found to have earlier style elongation, pollen presentation and pollinator visits compared with capitula manipulated to face west. East-facing capitula also sired more offspring than west-facing capitula and under some conditions produced heavier and better-filled seeds. Local ambient temperature change on the capitulum was found to be a key factor regulating the timing of style elongation, pollen emergence and pollinator visits. These results indicate that eastward capitulum orientation helps to control daily rhythms in floral temperature, with direct consequences on the timing of style elongation and pollen emergence, pollinator visitation, and plant fitness.


Assuntos
Helianthus , Polinização , Flores , Pólen , Temperatura
7.
Plant J ; 97(3): 603-615, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30394600

RESUMO

A network of environmental inputs and internal signaling controls plant growth, development and organ elongation. In particular, the growth-promoting hormone gibberellin (GA) has been shown to play a significant role in organ elongation. The use of tomato as a model organism to study elongation presents an opportunity to study the genetic control of internode-specific elongation in a eudicot species with a sympodial growth habit and substantial internodes that can and do respond to external stimuli. To investigate internode elongation, a mutant with an elongated hypocotyl and internodes but wild-type petioles was identified through a forward genetic screen. In addition to stem-specific elongation, this mutant, named tomato internode elongated -1 (tie-1) is more sensitive to the GA biosynthetic inhibitor paclobutrazol and has altered levels of intermediate and bioactive GAs compared with wild-type plants. The mutation responsible for the internode elongation phenotype was mapped to GA2oxidase 7, a class III GA 2-oxidase in the GA biosynthetic pathway, through a bulked segregant analysis and bioinformatic pipeline, and confirmed by transgenic complementation. Furthermore, bacterially expressed recombinant TIE protein was shown to have bona fide GA 2-oxidase activity. These results define a critical role for this gene in internode elongation and are significant because they further the understanding of the role of GA biosynthetic genes in organ-specific elongation.


Assuntos
Vias Biossintéticas , Giberelinas/metabolismo , Oxigenases de Função Mista/metabolismo , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Oxigenases de Função Mista/genética , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
New Phytol ; 226(3): 851-865, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31880321

RESUMO

Commercial tomato (Solanum lycopersicum) is one of the most widely grown vegetable crops worldwide. Heirloom tomatoes retain extensive genetic diversity and a considerable range of fruit quality and leaf morphological traits. Here the role of leaf morphology was investigated for its impact on fruit quality. Heirloom cultivars were grown in field conditions, and BRIX by yield (BY) and other traits were measured over a 14-wk period. The complex relationships among these morphological and physiological traits were evaluated using partial least-squares path modeling, and a consensus model was developed. Photosynthesis contributed strongly to vegetative biomass and sugar content of fruits but had a negative impact on yield. Conversely leaf shape, specifically rounder leaves, had a strong positive impact on both fruit sugar content and yield. Cultivars such as Stupice and Glacier, with very round leaves, had the highest performance in both fruit sugar and yield. Our model accurately predicted BY for two commercial cultivars using leaf shape data as input. This study revealed the importance of leaf shape to fruit quality in tomato, with rounder leaves having significantly improved fruit quality. This correlation was maintained across a range of diverse genetic backgrounds and shows the importance of leaf morphology in tomato crop improvement.


Assuntos
Solanum lycopersicum , Frutas , Solanum lycopersicum/genética , Fenótipo , Fotossíntese , Folhas de Planta
9.
Plant Physiol ; 178(4): 1720-1732, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30348816

RESUMO

Plants have sophisticated mechanisms for sensing neighbor shade. To maximize their ability to compete for light, plants respond to shade through enhanced elongation and physiological changes. The shade avoidance response affects many different organs and growth stages, yet the signaling pathways underlying this response have mostly been studied in seedlings. We assayed transcriptome changes in response to shade across a 2-d time course in the wild type and 12 Arabidopsis (Arabidopsis thaliana) mutants. The resulting temporal map of transcriptional responses to shade defines early and late responses in adult plants, enabling us to determine connections between key signaling genes and downstream responses. We found a pervasive and unexpectedly strong connection between shade avoidance and genes related to salicylic acid, suggesting salicylic acid signaling to be an important shade avoidance growth regulator. We tested this connection and found that several mutants disrupting salicylic acid levels or signaling were defective in shade avoidance. The effect of these mutations on shade avoidance was specific to petiole elongation; neither hypocotyl nor flowering time responses were altered, thereby defining important stage-specific differences in the downstream shade avoidance signaling pathway. Shade treatment did not change salicylic acid levels, indicating that the mediation of shade avoidance by salicylic acid is not dependent on the modulation of salicylic acid levels. These results demonstrate that salicylic acid pathway genes also are key components of petiole shade avoidance.


Assuntos
Arabidopsis/fisiologia , Redes Reguladoras de Genes , Redes e Vias Metabólicas/genética , Ácido Salicílico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Mutação , Oxilipinas/metabolismo , Fitocromo B/genética , Fitocromo B/metabolismo , Plantas Geneticamente Modificadas
10.
Plant Cell ; 27(8): 2088-94, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26220933

RESUMO

Plant biology is rapidly entering an era where we have the ability to conduct intricate studies that investigate how a plant interacts with the entirety of its environment. This requires complex, large studies to measure how plant genotypes simultaneously interact with a diverse array of environmental stimuli. Successful interpretation of the results from these studies requires us to transition away from the traditional standard of conducting an array of pairwise t tests toward more general linear modeling structures, such as those provided by the extendable ANOVA framework. In this Perspective, we present arguments for making this transition and illustrate how it will help to avoid incorrect conclusions in factorial interaction studies (genotype × genotype, genotype × treatment, and treatment × treatment, or higher levels of interaction) that are becoming more prevalent in this new era of plant biology.


Assuntos
Análise de Variância , Epistasia Genética , Interação Gene-Ambiente , Plantas/genética , Genótipo , Glucosinolatos/metabolismo , Modelos Genéticos , Mutação , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas/metabolismo
11.
PLoS Genet ; 11(4): e1004953, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25874869

RESUMO

Shade from neighboring plants limits light for photosynthesis; as a consequence, plants have a variety of strategies to avoid canopy shade and compete with their neighbors for light. Collectively the response to foliar shade is called the shade avoidance syndrome (SAS). The SAS includes elongation of a variety of organs, acceleration of flowering time, and additional physiological responses, which are seen throughout the plant life cycle. However, current mechanistic knowledge is mainly limited to shade-induced elongation of seedlings. Here we use phenotypic profiling of seedling, leaf, and flowering time traits to untangle complex SAS networks. We used over-representation analysis (ORA) of shade-responsive genes, combined with previous annotation, to logically select 59 known and candidate novel mutants for phenotyping. Our analysis reveals shared and separate pathways for each shade avoidance response. In particular, auxin pathway components were required for shade avoidance responses in hypocotyl, petiole, and flowering time, whereas jasmonic acid pathway components were only required for petiole and flowering time responses. Our phenotypic profiling allowed discovery of seventeen novel shade avoidance mutants. Our results demonstrate that logical selection of mutants increased success of phenotypic profiling to dissect complex traits and discover novel components.


Assuntos
Magnoliopsida/genética , Redes e Vias Metabólicas , Fenótipo , Fototropismo/genética , Ciclopentanos/metabolismo , Flores/fisiologia , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Magnoliopsida/metabolismo , Magnoliopsida/fisiologia , Mutação , Oxilipinas/metabolismo , Folhas de Planta/fisiologia , Sementes/fisiologia , Luz Solar
12.
Mol Ecol ; 26(20): 5528-5540, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28792639

RESUMO

Circadian clocks have evolved independently in all three domains of life, suggesting that internal mechanisms of time-keeping are adaptive in contemporary populations. However, the performance consequences of either discrete or quantitative clock variation have rarely been tested in field settings. Clock sensitivity of diverse segregating lines to the environment remains uncharacterized as do the statistical genetic parameters that determine evolutionary potential. In field studies with Arabidopsis thaliana, we found that major perturbations to circadian cycle length (referred to as clock period) via mutation reduce both survival and fecundity. Subtler adjustments via genomic introgression of naturally occurring alleles indicated that clock periods slightly >24 hr were adaptive, consistent with prior models describing how well the timing of biological processes is adjusted within a diurnal cycle (referred to as phase). In segregating recombinant inbred lines (RILs), circadian phase varied up to 2 hr across months of the growing season, and both period and phase expressed significant genetic variances. Performance metrics including developmental rate, size and fruit set were described by principal components (PC) analyses and circadian parameters correlated with the first PC, such that period lengths slightly >24 hr were associated with improved performance in multiple RIL sets. These experiments translate functional analyses of clock behaviour performed in controlled settings to natural ones, demonstrating that quantitative variation in circadian phase is highly responsive to seasonally variable abiotic factors. The results expand upon prior studies in controlled settings, showing that discrete and quantitative variation in clock phenotypes correlates with performance in nature.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Ritmo Circadiano , Variação Genética , Estações do Ano , Alelos , Relógios Circadianos , Mutação , Fenótipo
13.
Plant Physiol ; 172(1): 328-40, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27418589

RESUMO

Variation in gene expression, in addition to sequence polymorphisms, is known to influence developmental, physiological, and metabolic traits in plants. Genetic mapping populations have facilitated identification of expression quantitative trait loci (eQTL), the genetic determinants of variation in gene expression patterns. We used an introgression population developed from the wild desert-adapted Solanum pennellii and domesticated tomato (Solanum lycopersicum) to identify the genetic basis of transcript level variation. We established the effect of each introgression on the transcriptome and identified approximately 7,200 eQTL regulating the steady-state transcript levels of 5,300 genes. Barnes-Hut t-distributed stochastic neighbor embedding clustering identified 42 modules revealing novel associations between transcript level patterns and biological processes. The results showed a complex genetic architecture of global transcript abundance pattern in tomato. Several genetic hot spots regulating a large number of transcript level patterns relating to diverse biological processes such as plant defense and photosynthesis were identified. Important eQTL regulating transcript level patterns were related to leaf number and complexity as well as hypocotyl length. Genes associated with leaf development showed an inverse correlation with photosynthetic gene expression, but eQTL regulating genes associated with leaf development and photosynthesis were dispersed across the genome. This comprehensive eQTL analysis details the influence of these loci on plant phenotypes and will be a valuable community resource for investigations on the genetic effects of eQTL on phenotypic traits in tomato.


Assuntos
Fenômenos Biológicos/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Locos de Características Quantitativas/genética , Solanum lycopersicum/genética , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Hipocótilo/genética , Hipocótilo/crescimento & desenvolvimento , Solanum lycopersicum/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Solanum/genética , Solanum/crescimento & desenvolvimento , Especificidade da Espécie
14.
Plant Cell ; 26(9): 3616-29, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25271240

RESUMO

Leaf shape is mutable, changing in ways modulated by both development and environment within genotypes. A complete model of leaf phenotype would incorporate the changes in leaf shape during juvenile-to-adult phase transitions and the ontogeny of each leaf. Here, we provide a morphometric description of >33,000 leaflets from a set of tomato (Solanum spp) introgression lines grown under controlled environment conditions. We first compare the shape of these leaves, arising during vegetative development, with >11,000 previously published leaflets from a field setting and >11,000 leaflets from wild tomato relatives. We then quantify the changes in shape, across ontogeny, for successive leaves in the heteroblastic series. Using principal component analysis, we then separate genetic effects modulating (1) the overall shape of all leaves versus (2) the shape of specific leaves in the series, finding the former more heritable than the latter and comparing quantitative trait loci regulating each. Our results demonstrate that phenotype is highly contextual and that unbiased assessments of phenotype, for quantitative genetic or other purposes, would ideally sample the many developmental and environmental factors that modulate it.


Assuntos
Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Solanum lycopersicum/anatomia & histologia , Solanum lycopersicum/genética , Evolução Biológica , Endogamia , Modelos Biológicos , Fenótipo , Análise de Componente Principal , Locos de Características Quantitativas/genética
15.
Proc Natl Acad Sci U S A ; 111(25): E2616-21, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24927584

RESUMO

Despite a long-standing interest in the genetic basis of morphological diversity, the molecular mechanisms that give rise to developmental variation are incompletely understood. Here, we use comparative transcriptomics coupled with the construction of gene coexpression networks to predict a gene regulatory network (GRN) for leaf development in tomato and two related wild species with strikingly different leaf morphologies. The core network in the leaf developmental GRN contains regulators of leaf morphology that function in global cell proliferation with peripheral gene network modules (GNMs). The BLADE-ON-PETIOLE (BOP) transcription factor in one GNM controls the core network by altering effective concentration of the KNOTTED-like HOMEOBOX gene product. Comparative network analysis and experimental perturbations of BOP levels suggest that variation in BOP expression could explain the diversity in leaf complexity among these species through dynamic rewiring of interactions in the GRN. The peripheral location of the BOP-containing GNM in the leaf developmental GRN and the phenotypic mimics of evolutionary diversity caused by alteration in BOP levels identify a key role for this GNM in canalizing the leaf morphospace by modifying the maturation schedule of leaves to create morphological diversity.


Assuntos
Redes Reguladoras de Genes/fisiologia , Folhas de Planta , Proteínas de Plantas , Solanum , Fatores de Transcrição , Transcriptoma/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Solanum/anatomia & histologia , Solanum/genética , Solanum/metabolismo , Especificidade da Espécie , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Mol Ecol ; 25(5): 1122-40, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26800256

RESUMO

Floral attraction traits can significantly affect pollinator visitation patterns, but adaptive evolution of these traits may be constrained by correlations with other traits. In some cases, molecular pathways contributing to floral attraction are well characterized, offering the opportunity to explore loci potentially underlying variation among individuals. Here, we quantify the range of variation in floral UV patterning (i.e. UV 'bulls-eye nectar guides) among crop and wild accessions of Brassica rapa. We then use experimental crosses to examine the genetic architecture, candidate loci and biochemical underpinnings of this patterning as well as phenotypic manipulations to test the ecological impact. We find qualitative variation in UV patterning between wild (commonly lacking UV patterns) and crop (commonly exhibiting UV patterns) accessions. Similar to the majority of crops, recombinant inbred lines (RILs) derived from an oilseed crop × WI fast-plant® cross exhibit UV patterns, the size of which varies extensively among genotypes. In RILs, we further observe strong statistical-genetic and QTL correlations within petal morphological traits and within measurements of petal UV patterning; however, correlations between morphology and UV patterning are weak or nonsignificant, suggesting that UV patterning is regulated and may evolve independently of overall petal size. HPLC analyses reveal a high concentration of sinapoyl glucose in UV-absorbing petal regions, which, in concert with physical locations of UV-trait QTLs, suggest a regulatory and structural gene as candidates underlying observed quantitative variation. Finally, insects prefer flowers with UV bulls-eye patterns over those that lack patterns, validating the importance of UV patterning in pollen-limited populations of B. rapa.


Assuntos
Brassica rapa/genética , Flores/anatomia & histologia , Insetos/fisiologia , Polinização , Raios Ultravioleta , Animais , Brassica rapa/anatomia & histologia , Brassica rapa/química , Cinamatos/química , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/genética , Flores/química , Flores/genética , Genética Populacional , Genótipo , Glucosídeos/química , Fenótipo , Locos de Características Quantitativas , Quercetina/análogos & derivados , Quercetina/química
17.
Plant Physiol ; 169(3): 2030-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26381315

RESUMO

Plants sense the foliar shade of competitors and alter their developmental programs through the shade-avoidance response. Internode and petiole elongation, and changes in overall leaf area and leaf mass per area, are the stereotypical architectural responses to foliar shade in the shoot. However, changes in leaf shape and complexity in response to shade remain incompletely, and qualitatively, described. Using a meta-analysis of more than 18,000 previously published leaflet outlines, we demonstrate that shade avoidance alters leaf shape in domesticated tomato (Solanum lycopersicum) and wild relatives. The effects of shade avoidance on leaf shape are subtle with respect to individual traits but are combinatorially strong. We then seek to describe the developmental origins of shade-induced changes in leaf shape by swapping plants between light treatments. Leaf size is light responsive late into development, but patterning events, such as stomatal index, are irrevocably specified earlier. Observing that shade induces increases in shoot apical meristem size, we then describe gene expression changes in early leaf primordia and the meristem using laser microdissection. We find that in leaf primordia, shade avoidance is not mediated through canonical pathways described in mature organs but rather through the expression of KNOTTED1-LIKE HOMEOBOX and other indeterminacy genes, altering known developmental pathways responsible for patterning leaf shape. We also demonstrate that shade-induced changes in leaf primordium gene expression largely do not overlap with those found in successively initiated leaf primordia, providing evidence against classic hypotheses that shaded leaf morphology results from the prolonged production of juvenile leaf types.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos da radiação , Proteínas de Homeodomínio/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Proteínas de Homeodomínio/genética , Luz , Solanum lycopersicum/anatomia & histologia , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Meristema/anatomia & histologia , Meristema/genética , Meristema/fisiologia , Meristema/efeitos da radiação , Modelos Biológicos , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética
18.
Plant Cell ; 25(7): 2465-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23872539

RESUMO

Introgression lines (ILs), in which genetic material from wild tomato species is introgressed into a domesticated background, have been used extensively in tomato (Solanum lycopersicum) improvement. Here, we genotype an IL population derived from the wild desert tomato Solanum pennellii at ultrahigh density, providing the exact gene content harbored by each line. To take advantage of this information, we determine IL phenotypes for a suite of vegetative traits, ranging from leaf complexity, shape, and size to cellular traits, such as stomatal density and epidermal cell phenotypes. Elliptical Fourier descriptors on leaflet outlines provide a global analysis of highly heritable, intricate aspects of leaf morphology. We also demonstrate constraints between leaflet size and leaf complexity, pavement cell size, and stomatal density and show independent segregation of traits previously assumed to be genetically coregulated. Meta-analysis of previously measured traits in the ILs shows an unexpected relationship between leaf morphology and fruit sugar levels, which RNA-Seq data suggest may be attributable to genetically coregulated changes in fruit morphology or the impact of leaf shape on photosynthesis. Together, our results both improve upon the utility of an important genetic resource and attest to a complex, genetic basis for differences in leaf morphology between natural populations.


Assuntos
Frutas/genética , Folhas de Planta/genética , Locos de Características Quantitativas/genética , Solanum lycopersicum/genética , Mapeamento Cromossômico , Frutas/anatomia & histologia , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Genoma de Planta/genética , Genótipo , Solanum lycopersicum/anatomia & histologia , Solanum lycopersicum/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Solanum/anatomia & histologia , Solanum/genética , Solanum/crescimento & desenvolvimento , Especificidade da Espécie
19.
Proc Natl Acad Sci U S A ; 110(28): E2655-62, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23803858

RESUMO

Although applied over extremely short timescales, artificial selection has dramatically altered the form, physiology, and life history of cultivated plants. We have used RNAseq to define both gene sequence and expression divergence between cultivated tomato and five related wild species. Based on sequence differences, we detect footprints of positive selection in over 50 genes. We also document thousands of shifts in gene-expression level, many of which resulted from changes in selection pressure. These rapidly evolving genes are commonly associated with environmental response and stress tolerance. The importance of environmental inputs during evolution of gene expression is further highlighted by large-scale alteration of the light response coexpression network between wild and cultivated accessions. Human manipulation of the genome has heavily impacted the tomato transcriptome through directed admixture and by indirectly favoring nonsynonymous over synonymous substitutions. Taken together, our results shed light on the pervasive effects artificial and natural selection have had on the transcriptomes of tomato and its wild relatives.


Assuntos
Seleção Genética , Solanum lycopersicum/genética , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genes de Plantas
20.
Plant Physiol ; 165(1): 175-85, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24623850

RESUMO

Female control of nonrandom mating has never been genetically established, despite being linked to inbreeding depression and sexual selection. In order to map the loci that control female-mediated nonrandom mating, we constructed a new advanced intercross recombinant inbred line (RIL) population derived from a cross between Arabidopsis (Arabidopsis thaliana) accessions Vancouver (Van-0) and Columbia (Col-0) and mapped quantitative trait loci (QTLs) responsible for nonrandom mating and seed yield traits. We genotyped a population of 490 RILs. A subset of these lines was used to construct an expanded map of 1,061.4 centimorgans with an average interval of 6.7±5.3 centimorgans between markers. QTLs were then mapped for female- and male-mediated nonrandom mating and seed yield traits. To map the genetic loci responsible for female-mediated nonrandom mating and seed yield, we performed mixed pollinations with genetically marked Col-0 pollen and Van-0 pollen on RIL pistils. To map the loci responsible for male-mediated nonrandom mating and seed yield, we performed mixed pollinations with genetically marked Col-0 and RIL pollen on Van-0 pistils. Composite interval mapping of these data identified four QTLs that control female-mediated nonrandom mating and five QTLs that control female-mediated seed yield. We also identified four QTLs that control male-mediated nonrandom mating and three QTLs that control male-mediated seed yield. Epistasis analysis indicates that several of these loci interact. To our knowledge, the results of these experiments represent the first time female-mediated nonrandom mating has been genetically defined.


Assuntos
Arabidopsis/genética , Cruzamentos Genéticos , Endogamia , Recombinação Genética/genética , Mapeamento Cromossômico , Epistasia Genética , Marcadores Genéticos , Padrões de Herança/genética , Fenótipo , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável , Reprodução , Sementes/genética , Sementes/crescimento & desenvolvimento
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