Base de dados : MEDLINE
Pesquisa : G05.090.403.590 [Categoria DeCS]
Referências encontradas : 308 [refinar]
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[PMID]:28981570
[Au] Autor:Camargo ID; Nattero J; Careaga SA; Núñez-Farfán J
[Ad] Endereço:Laboratorio de Genética Ecológica y Evolución, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de México, Mexico City, 04510 Distrito Federal, Mexico.
[Ti] Título:Flower-level developmental plasticity to nutrient availability in Datura stramonium: implications for the mating system.
[So] Source:Ann Bot;120(4):603-615, 2017 Oct 17.
[Is] ISSN:1095-8290
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Background and Aims: Studies of phenotypic plasticity in plants have mainly focused on (1) the effect of environmental variation on whole-plant traits related to the number of modules rather than on (2) the phenotypic consequences of environmental variation in traits of individual modules. Since environmental and developmental factors can produce changes in traits related to the mating system, this study used the second approach to investigate whether within-individual variation in herkogamy-related traits is affected by the environment during plant development in two populations of Datura stramonium , an annual herb with a hypothesized persistent mixed mating system, and to determine which morphological traits may promote self-fertilization. Methods: Full-sib families of two Mexican populations of D. stramonium , with contrasting ecological histories, were grown under low, mid and high nutrient availability to investigate the effects of genetic, environmental and within-plant flower position on flower size, corolla, stamen and pistil lengths, and herkogamy. Key Results: Populations showed differences in familial variation, plasticity and familial differences in plasticity in most floral traits analysed. In one population (Ticumán), the effect of flower position on trait variation varied among families, whereas in the other (Pedregal) the effect of flower position interacted with the nutrient environment. Flower size varied with the position of flowers, but in the opposite direction between populations in low nutrients; a systematic within-plant trend of reduction in flower size, pistil length and herkogamy with flower position increased the probability of self-fertilization in the Pedregal population. Conclusions: Besides genetic variation in floral traits between and within populations, environmental variation affects phenotypic floral trait values at the whole-plant level, as well as among flower positions. The interaction between flower position and nutrient environment can affect the plant's mating system, and this differs between populations. Thus, reductions in herkogamy with flower positions may be expected in environments with either low pollinator abundance or low nutrients.
[Mh] Termos MeSH primário: Datura stramonium/crescimento & desenvolvimento
Flores/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Datura stramonium/anatomia & histologia
Datura stramonium/fisiologia
Meio Ambiente
Flores/anatomia & histologia
Flores/fisiologia
Fenótipo
Polinização/fisiologia
Reprodução/fisiologia
Autofertilização/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171006
[St] Status:MEDLINE
[do] DOI:10.1093/aob/mcx093


  2 / 308 MEDLINE  
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[PMID]:28792961
[Au] Autor:Penley MJ; Ha GT; Morran LT
[Ad] Endereço:Department of Biology, Emory University, Atlanta, Georgia, United States of America.
[Ti] Título:Evolution of Caenorhabditis elegans host defense under selection by the bacterial parasite Serratia marcescens.
[So] Source:PLoS One;12(8):e0181913, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Parasites can impose strong selection on hosts. In response, some host populations have adapted via the evolution of defenses that prevent or impede infection by parasites. However, host populations have also evolved life history shifts that maximize host fitness despite infection. Outcrossing and self-fertilization can have contrasting effects on evolutionary trajectories of host populations. While selfing and outcrossing are known to affect the rate at which host populations adapt in response to parasites, these mating systems may also influence the specific traits that underlie adaptation to parasites. Here, we determined the role of evolved host defense versus altered life history,in mixed mating (selfing and outcrossing) and obligately outcrossing C. elegans host populations after experimental evolution with the bacterial parasite, S. marcescens. Similar to previous studies, we found that both mixed mating and obligately outcrossing host populations adapted to S. marcescens exposure, and that the obligately outcrossing populations exhibited the greatest rates of adaptation. Regardless of the host population mating system, exposure to parasites did not significantly alter reproductive timing or total fecundity over the course of experimental evolution. However, both mixed mating and obligately outcrossing host populations exhibited significantly reduced mortality rates in the presence of the parasite after experimental evolution. Therefore, adaptation in both the mixed mating and obligately outcrossing populations was driven, at least in part, by the evolution of increased host defense and not changes in host life history. Thus, the host mating system altered the rate of adaptation, but not the nature of adaptive change in the host populations.
[Mh] Termos MeSH primário: Adaptação Fisiológica/fisiologia
Caenorhabditis elegans/crescimento & desenvolvimento
Caenorhabditis elegans/microbiologia
Interações Hospedeiro-Patógeno/fisiologia
Serratia marcescens/patogenicidade
[Mh] Termos MeSH secundário: Animais
Evolução Biológica
Caenorhabditis elegans/imunologia
Fertilidade
Seleção Genética
Autofertilização/fisiologia
Serratia marcescens/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171003
[Lr] Data última revisão:
171003
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170810
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181913


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[PMID]:28650458
[Au] Autor:Takada Y; Murase K; Shimosato-Asano H; Sato T; Nakanishi H; Suwabe K; Shimizu KK; Lim YP; Takayama S; Suzuki G; Watanabe M
[Ad] Endereço:Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan.
[Ti] Título:Duplicated pollen-pistil recognition loci control intraspecific unilateral incompatibility in Brassica rapa.
[So] Source:Nat Plants;3:17096, 2017 Jun 26.
[Is] ISSN:2055-0278
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In plants, cell-cell recognition is a crucial step in the selection of optimal pairs of gametes to achieve successful propagation of progeny. Flowering plants have evolved various genetic mechanisms, mediated by cell-cell recognition, to enable their pistils to reject self-pollen, thus preventing inbreeding and the consequent reduced fitness of progeny (self-incompatibility, SI), and to reject foreign pollen from other species, thus maintaining species identity (interspecific incompatibility) . In the genus Brassica, the SI system is regulated by an S-haplotype-specific interaction between a stigma-expressed female receptor (S receptor kinase, SRK) and a tapetum cell-expressed male ligand (S locus protein 11, SP11), encoded by their respective polymorphic genes at the S locus . However, the molecular mechanism for recognition of foreign pollen, leading to reproductive incompatibility, has not yet been identified. Here, we show that recognition between a novel pair of proteins, a pistil receptor SUI1 (STIGMATIC UNILATERAL INCOMPATIBILITY 1) and a pollen ligand PUI1 (POLLEN UNILATERAL INCOMPATIBILITY 1), triggers unilateral reproductive incompatibility between plants of two geographically distant self-incompatible Brassica rapa lines, even though crosses would be predicted to be compatible based on the S haplotypes of pollen and stigma. Interestingly, SUI1 and PUI1 are similar to the SI genes, SRK and SP11, respectively, and are maintained as cryptic incompatibility genes in these two populations. The duplication of the SRK and SP11 followed by reciprocal loss in different populations would provide a molecular mechanism of the emergence of a reproductive barrier in allopatry.
[Mh] Termos MeSH primário: Brassica rapa/genética
Flores/genética
Pólen/genética
[Mh] Termos MeSH secundário: Brassica rapa/citologia
Brassica rapa/fisiologia
Polinização/genética
Autofertilização/genética
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170705
[Lr] Data última revisão:
170705
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170627
[St] Status:MEDLINE
[do] DOI:10.1038/nplants.2017.96


  4 / 308 MEDLINE  
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[PMID]:28394901
[Au] Autor:Pan C; Li Q; Lu Y; Zhang J; Yang X; Li X; Li L; Liu W
[Ad] Endereço:National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
[Ti] Título:Chromosomal localization of genes conferring desirable agronomic traits from Agropyron cristatum chromosome 1P.
[So] Source:PLoS One;12(4):e0175265, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Agropyron cristatum (L.) Gaertn. (2n = 4x = 28, PPPP), a wild relative of common wheat, possesses many potentially valuable genes for wheat breeding. To transfer these genes into wheat, a series of wheat-A. cristatum derivatives have been obtained in our laboratory. In this study, a wheat-A. cristatum derivative II-3-1 was obtained, which was proven to contain a 1P (1A) disomic substitution and 2P disomic addition line with 40 wheat chromosomes and two pairs of A. cristatum chromosomes by genomic in situ hybridization (GISH) and molecular markers analysis. By further backcrossing with the wheat parent Fukuhokomugi (Fukuho) and self-fertilization, three different lines were separated from II-3-1, including wheat-A. cristatum 1P disomic addition line II-3-1a, 2P disomic addition line II-3-1b and 1P (1A) disomic substitution line II-3-1c. Because 2P addition line had been reported before, we aimed to investigate 1P disomic addition line II-3-1a and wheat-A. cristatum 1P (1A) disomic substitution line II-3-1c. Analysis of different genetic populations demonstrated that 1P chromosome harbored multiple agronomic traits, such as elevated spike length, increased tillering ability, reduced plant height and spikelet density. Besides, bristles on the glume ridges as an important morphological marker was located on 1P chromosome. Therefore, the novel 1P addition and substitution lines will be used as important genetic materials to widen the genetic resources of wheat.
[Mh] Termos MeSH primário: Agropyron/genética
Cromossomos de Plantas
Triticum/genética
[Mh] Termos MeSH secundário: Agropyron/metabolismo
Hibridização in Situ Fluorescente
Meiose
Fenótipo
Melhoramento Vegetal
Raízes de Plantas/genética
Raízes de Plantas/metabolismo
Autofertilização
Triticum/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170411
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0175265


  5 / 308 MEDLINE  
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[PMID]:28361703
[Au] Autor:Sun S; Klebaner F; Tian T
[Ad] Endereço:School of Mathematical Sciences, Monash University, Melbourne, VIC 3800, Australia.
[Ti] Título:Mathematical modelling for variations of inbreeding populations fitness with single and polygenic traits.
[So] Source:BMC Genomics;18(Suppl 2):196, 2017 03 14.
[Is] ISSN:1471-2164
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Inbreeding mating has been widely accepted as the key mechanism to enhance homozygosity which normally will decrease the fitness of the population. Although this result has been validated by a large amount of biological data from the natural populations, a mathematical proof of these experimental discoveries is still not complete. A related question is whether we can extend the well-established result regarding the mean fitness from a randomly mating population to inbreeding populations. A confirmative answer may provide insights into the frequent occurrence of self-fertilization populations. RESULTS: This work presents a theoretic proof of the result that, for a large inbreeding population with directional relative genotype fitness, the mean fitness of population increases monotonically. However, it cannot be extended to the case with over-dominant genotype fitness. In addition, by employing multiplicative intersection hypothesis, we prove that inbreeding mating does decrease the mean fitness of polygenic population in general, but does not decrease the mean fitness with mixed dominant-recessive genotypes. We also prove a novel result that inbreeding depression depends on not only the mating pattern but also genetic structure of population. CONCLUSIONS: For natural inbreeding populations without serious inbreeding depression, our theoretical analysis suggests the majority of its genotypes should be additive or dominant-recessive genotypes. This result gives a reason to explain why many hermaphroditism populations do not show severe inbreeding depression. In addition, the calculated purging rate shows that inbreeding mating purges the deleterious mutants more efficiently than randomly mating does.
[Mh] Termos MeSH primário: Consanguinidade
Transtornos do Desenvolvimento Sexual
Genética Populacional
Modelos Genéticos
Autofertilização
[Mh] Termos MeSH secundário: Animais
Aptidão Genética
Genótipo
Homozigoto
Seres Humanos
Plantas/genética
Seleção Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170401
[St] Status:MEDLINE
[do] DOI:10.1186/s12864-017-3492-1


  6 / 308 MEDLINE  
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[PMID]:28177324
[Au] Autor:Bürkli A; Sieber N; Seppälä K; Jokela J
[Ad] Endereço:EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Department of Aquatic Ecology, Dübendorf, Switzerland.
[Ti] Título:Comparing direct and indirect selfing rate estimates: when are population-structure estimates reliable?
[So] Source:Heredity (Edinb);118(6):525-533, 2017 Jun.
[Is] ISSN:1365-2540
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The rate of self-fertilization (that is, selfing) is a key evolutionary parameter in hermaphroditic species, yet obtaining accurate estimates of selfing rates in natural populations can be technically challenging. Most published estimates are derived from population-level heterozygote deficiency (that is, F ) or identity disequilibria (for example, the software RMES (robust multilocus estimate of selfing)). These indirect methods can be applied to population genetic survey data, whereas direct methods using progeny arrays require much larger data sets that are often difficult to collect in natural populations or even require captive breeding. Unfortunately, indirect methods rely on assumptions that can be problematic, such as negating biparental inbreeding, inbreeding disequilibrium and (for F ) the presence of null alleles. The performance of indirect estimates against progeny-array estimates is still largely unknown. Here we used both direct progeny-array and indirect population-level methods to estimate the selfing rate in a single natural population of the simultaneously hermaphroditic freshwater snail Radix balthica throughout its reproductive lifespan using 10 highly polymorphic microsatellites. We found that even though progeny arrays (n=1034 field-collected embryos from 60 families) did not reveal a single selfed embryo, F -based selfing rates (n=316 adults) were significantly positive in all 6 sequential population samples. Including a locus with a high frequency of null alleles further biased F -based estimates. Conversely, RMES-based estimates were very similar to progeny-array estimates and proved insensitive to null alleles. The assumptions made by RMES were thus either met or irrelevant in this particular population, making RMES a valid, cost-efficient alternative to progeny arrays.
[Mh] Termos MeSH primário: Genética Populacional/métodos
Endogamia
Autofertilização
Caramujos/genética
[Mh] Termos MeSH secundário: Alelos
Animais
Água Doce
Repetições de Microssatélites
Modelos Biológicos
Óvulo/fisiologia
Caramujos/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170209
[St] Status:MEDLINE
[do] DOI:10.1038/hdy.2017.1


  7 / 308 MEDLINE  
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[PMID]:28141838
[Au] Autor:Walsh RP; Michaels HJ
[Ad] Endereço:Department of Conservation, The Toledo Zoological Society, Toledo, Ohio, United States of America.
[Ti] Título:When it pays to cheat: Examining how generalized food deception increases male and female fitness in a terrestrial orchid.
[So] Source:PLoS One;12(1):e0171286, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Experimental manipulations of floral nectar in food deceptive species can reveal insights into the evolutionary consequences of the deceptive strategy. When coupled to pollen tracking, the effects of the deceptive pollination syndrome on both male and female reproductive success may be quantified. Attraction of pollinators in deceit-pollinated species often relies on producing a conspicuous floral display which may increase visibility to pollinators, but in-turn may increase within plant selfing. METHODOLOGY: To understand the role of deception in Orchidaceae reproduction we studied Cypripedium candidum. All species of the Cypripedium genus employ a generalized food deceptive pollination strategy and have been suggested as a model system for the study of pollinator deception. We conducted a nectar addition experiment that randomly assigned the four plants closest to a transect point to receive one of four histochemical dyes. Two individuals selected for nectar addition in each of altogether 25 blocks received 2µl of 25% sucrose solution in the labellum of each flower, while two others received no artificial nectar. Number of fruits produced, fruit mass and fruit abortion were scored at the end of the four-month experiment. RESULTS: Nectar addition increased (p<0.0001) self-pollination and pollen discounting by nearly 3x, while plants not receiving nectar had greater (p<0.0001) numbers of non-self pollinia deposited and lower rates of pollen discounting. There was a non-significant (p = 0.0645) trend for deceptive plants to set more fruit, while presence of nectar did not affect pollen export. CONCLUSIONS: This study demonstrates the adaptive advantages of food deception by showing a concurrent reduction in particular male and female functions when a food reward is restored to a deceptive flower. We found generalized food deception to not only decrease inbreeding depression in the system, but concurrently have no effect on pollinator attraction and fruit set when compared with rewarding flowers.
[Mh] Termos MeSH primário: Flores/fisiologia
Orchidaceae/fisiologia
Néctar de Plantas
[Mh] Termos MeSH secundário: Análise de Variância
Cruzamentos Genéticos
Frutas/fisiologia
Análise dos Mínimos Quadrados
Reprodução
Sementes/fisiologia
Autofertilização
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Plant Nectar)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170809
[Lr] Data última revisão:
170809
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170201
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0171286


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[PMID]:28139832
[Au] Autor:Uecker H
[Ad] Endereço:IST Austria, Am Campus 1, 3400, Klosterneuburg, Austria.
[Ti] Título:Evolutionary rescue in randomly mating, selfing, and clonal populations.
[So] Source:Evolution;71(4):845-858, 2017 Apr.
[Is] ISSN:1558-5646
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Severe environmental change can drive a population extinct unless the population adapts in time to the new conditions ("evolutionary rescue"). How does biparental sexual reproduction influence the chances of population persistence compared to clonal reproduction or selfing? In this article, we set up a one-locus two-allele model for adaptation in diploid species, where rescue is contingent on the establishment of the mutant homozygote. Reproduction can occur by random mating, selfing, or clonally. Random mating generates and destroys the rescue mutant; selfing is efficient at generating it but at the same time depletes the heterozygote, which can lead to a low mutant frequency in the standing genetic variation. Due to these (and other) antagonistic effects, we find a nontrivial dependence of population survival on the rate of sex/selfing, which is strongly influenced by the dominance coefficient of the mutation before and after the environmental change. Importantly, since mating with the wild-type breaks the mutant homozygote up, a slow decay of the wild-type population size can impede rescue in randomly mating populations.
[Mh] Termos MeSH primário: Adaptação Biológica
Evolução Biológica
Variação Genética
[Mh] Termos MeSH secundário: Homozigoto
Modelos Genéticos
Reprodução
Autofertilização
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170201
[St] Status:MEDLINE
[do] DOI:10.1111/evo.13191


  9 / 308 MEDLINE  
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[PMID]:28116770
[Au] Autor:Moeller DA; Briscoe Runquist RD; Moe AM; Geber MA; Goodwillie C; Cheptou PO; Eckert CG; Elle E; Johnston MO; Kalisz S; Ree RH; Sargent RD; Vallejo-Marin M; Winn AA
[Ad] Endereço:Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, 55108, USA.
[Ti] Título:Global biogeography of mating system variation in seed plants.
[So] Source:Ecol Lett;20(3):375-384, 2017 Mar.
[Is] ISSN:1461-0248
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Latitudinal gradients in biotic interactions have been suggested as causes of global patterns of biodiversity and phenotypic variation. Plant biologists have long speculated that outcrossing mating systems are more common at low than high latitudes owing to a greater predictability of plant-pollinator interactions in the tropics; however, these ideas have not previously been tested. Here, we present the first global biogeographic analysis of plant mating systems based on 624 published studies from 492 taxa. We found a weak decline in outcrossing rate towards higher latitudes and among some biomes, but no biogeographic patterns in the frequency of self-incompatibility. Incorporating life history and growth form into biogeographic analyses reduced or eliminated the importance of latitude and biome in predicting outcrossing or self-incompatibility. Our results suggest that biogeographic patterns in mating system are more likely a reflection of the frequency of life forms across latitudes rather than the strength of plant-pollinator interactions.
[Mh] Termos MeSH primário: Cycadopsida/fisiologia
Magnoliopsida/fisiologia
Polinização
Autofertilização
[Mh] Termos MeSH secundário: Biodiversidade
Dispersão Vegetal
Reprodução
[Pt] Tipo de publicação:LETTER
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170125
[St] Status:MEDLINE
[do] DOI:10.1111/ele.12738


  10 / 308 MEDLINE  
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[PMID]:28087777
[Au] Autor:Novikova PY; Tsuchimatsu T; Simon S; Nizhynska V; Voronin V; Burns R; Fedorenko OM; Holm S; Säll T; Prat E; Marande W; Castric V; Nordborg M
[Ad] Endereço:Gregor Mendel Institute, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, Austria.
[Ti] Título:Genome Sequencing Reveals the Origin of the Allotetraploid Arabidopsis suecica.
[So] Source:Mol Biol Evol;34(4):957-968, 2017 Apr 01.
[Is] ISSN:1537-1719
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Polyploidy is an example of instantaneous speciation when it involves the formation of a new cytotype that is incompatible with the parental species. Because new polyploid individuals are likely to be rare, establishment of a new species is unlikely unless polyploids are able to reproduce through self-fertilization (selfing), or asexually. Conversely, selfing (or asexuality) makes it possible for polyploid species to originate from a single individual-a bona fide speciation event. The extent to which this happens is not known. Here, we consider the origin of Arabidopsis suecica, a selfing allopolyploid between Arabidopsis thaliana and Arabidopsis arenosa, which has hitherto been considered to be an example of a unique origin. Based on whole-genome re-sequencing of 15 natural A. suecica accessions, we identify ubiquitous shared polymorphism with the parental species, and hence conclusively reject a unique origin in favor of multiple founding individuals. We further estimate that the species originated after the last glacial maximum in Eastern Europe or central Eurasia (rather than Sweden, as the name might suggest). Finally, annotation of the self-incompatibility loci in A. suecica revealed that both loci carry non-functional alleles. The locus inherited from the selfing A. thaliana is fixed for an ancestral non-functional allele, whereas the locus inherited from the outcrossing A. arenosa is fixed for a novel loss-of-function allele. Furthermore, the allele inherited from A. thaliana is predicted to transcriptionally silence the allele inherited from A. arenosa, suggesting that loss of self-incompatibility may have been instantaneous.
[Mh] Termos MeSH primário: Arabidopsis/genética
Mapeamento Cromossômico/métodos
Especiação Genética
[Mh] Termos MeSH secundário: Sequência de Bases/genética
Variação Genética/genética
Genoma/genética
Genoma de Planta/genética
Filogenia
Poliploidia
Autofertilização/genética
Análise de Sequência de DNA/métodos
Tetraploidia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170115
[St] Status:MEDLINE
[do] DOI:10.1093/molbev/msw299



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