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1.
Sci Rep ; 11(1): 11731, 2021 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-34083611

RESUMEN

Adrinandra megaphylla Hu is a medicinal plant belonging to the Adrinandra genus, which is well-known for its potential health benefits due to its bioactive compounds. This study aimed to assemble and annotate the chloroplast genome of A. megaphylla as well as compare it with previously published cp genomes within the Adrinandra genus. The chloroplast genome was reconstructed using de novo and reference-based assembly of paired-end reads generated by long-read sequencing of total genomic DNA. The size of the chloroplast genome was 156,298 bp, comprised a large single-copy (LSC) region of 85,688 bp, a small single-copy (SSC) region of 18,424 bp, and a pair of inverted repeats (IRa and IRb) of 26,093 bp each; and a total of 51 SSRs and 48 repeat structures were detected. The chloroplast genome includes a total of 131 functional genes, containing 86 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. The A. megaphylla chloroplast genome indicated that gene content and structure are highly conserved. The phylogenetic reconstruction using complete cp sequences, matK and trnL genes from Pentaphylacaceae species exhibited a genetic relationship. Among them, matK sequence is a better candidate for phylogenetic resolution. This study is the first report for the chloroplast genome of the A. megaphylla.


Asunto(s)
Ericales/clasificación , Ericales/genética , Genoma del Cloroplasto , Genómica , Plantas Medicinales/clasificación , Plantas Medicinales/genética , Codón , Biología Computacional/métodos , Genómica/métodos , Anotación de Secuencia Molecular , Estructura Molecular , Sistemas de Lectura Abierta , Filogenia , Secuencias Repetitivas de Ácidos Nucleicos , Secuenciación Completa del Genoma
2.
Mol Phylogenet Evol ; 126: 92-104, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29574271

RESUMEN

Arid biomes are particularly prominent in the Neotropics providing some of its most emblematic landscapes and a substantial part of its species diversity. To understand some of the evolutionary processes underlying the speciation of lineages in the Mexican Deserts, the diversification of Fouquieria is investigated, which includes eleven species, all endemic to the warm deserts and dry subtropical regions of North America. Using a phylogeny from plastid DNA sequences with samples of individuals from populations of all the species recognized in Fouquieria, we estimate divergence times, test for temporal diversification heterogeneity, test for geographical structure, and conduct ancestral area reconstruction. Fouquieria is an ancient lineage that diverged from Polemoniaceae ca. 75.54 Ma. A Mio-Pliocene diversification of Fouquieria with vicariance, associated with Neogene orogenesis underlying the early development of regional deserts is strongly supported. Test for temporal diversification heterogeneity indicates that during its evolutionary history, Fouquieria had a drastic diversification rate shift at ca.12.72 Ma, agreeing with hypotheses that some of the lineages in North American deserts diversified as early as the late Miocene to Pliocene, and not during the Pleistocene. Long-term diversification dynamics analyses suggest that extinction also played a significant role in Fouquieria's evolution, with a very high rate at the onset of the process. From the late Miocene onwards, Fouquieria underwent substantial diversification change, involving high speciation decreasing to the present and negligible extinction, which is congruent with its scant fossil record during this period. Geographic phylogenetic structure and the pattern of most sister species inhabiting different desert nucleus support that isolation by distance could be the main driver of speciation.


Asunto(s)
Clima Desértico , Ericales/clasificación , Filogenia , Biodiversidad , Fósiles , Especiación Genética , Geografía , Funciones de Verosimilitud , América del Norte , Programas Informáticos , Factores de Tiempo , Estados Unidos
3.
Mol Phylogenet Evol ; 121: 198-211, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29360618

RESUMEN

Relationships among the genera of the small, woody family Styracaceae and among families of the large, diverse order Ericales have resisted complete resolution with sequences from one or a few genes. We used plastome sequencing to attempt to resolve the backbone relationships of Styracaceae and Ericales and to explore plastome structural evolution. Complete plastomes for 23 species are newly reported here, including 18 taxa of Styracaceae and five of Ericales (including species of Sapotaceae, Clethraceae, Symplocaceae, and Diapensiaceae). Combined with publicly available complete plastome data, this resulted in a data set of 60 plastomes, including 11 of the 12 genera of Styracaceae and 12 of 22 families of Ericales. Styracaceae plastomes were found to possess the quadripartite structure typical of angiosperms, with sizes ranging from 155 to 159 kb. Most of the plastomes were found to possess the full complement of typical angiosperm plastome genes. Unusual structural features were detected in plastomes of Alniphyllum and Bruinsmia, including the presence of a large 20-kb inversion (14 genes) in the Large Single-Copy region, the loss or pseudogenization of the clpP and accD genes in Bruinsmia, and the loss of the first exon of rps16 in B. styracoides. Likewise, the second intron from clpP was found to be lost in Alniphyllum and Huodendron. Phylogenomic analyses including all 79 plastid protein-coding genes provided improved resolution for relationships among the genera of Styracaceae and families of Ericales. Styracaceae was strongly supported as monophyletic, with Styrax, Huodendron, and a clade of Alniphyllum + Bruinsmia successively sister to the remainder of the family, all with strong support. All genera of Styracaceae were recovered as monophyletic, except for Halesia and Pterostyrax, which were each recovered as polyphyletic with strong support. Within Ericales, all families were recovered as monophyletic with strong support, with Balsaminaceae sister to remaining Ericales. Most relationships recovered in plastome analyses are congruent with previous analyses based on smaller data sets. Our results demonstrate the power of plastid phylogenomics to improve phylogenetic hypotheses among genera and families, and provide new insight into plastome evolution across Ericales.


Asunto(s)
Ericales/clasificación , Genómica , Filogenia , Plastidios/genética , Styracaceae/clasificación , Styracaceae/genética , Secuencia de Bases , Evolución Molecular , Genoma de Plastidios , Intrones/genética , Funciones de Verosimilitud , Polimorfismo de Nucleótido Simple/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética
4.
Sci Rep ; 7(1): 16677, 2017 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-29192234

RESUMEN

Galling insects are a highly sophisticated herbivore group on Caryocar brasiliense, a tree that represents the main income source for many communities. The effect of architectural diversity of C. brasiliense trees on galling insect community diversity and abundance was studied. The abundance of adult insects and galled leaves were seven and 1.6 times higher in trees with a greater height/width of canopy (RHW) ratio, respectively. Gall parasitoid richness was 1.8 times greater on trees with higher RHW. Zelus armillatus (Lepeletier & Serville) (Hemiptera: Reduviidae) and ant numbers were 5.8 and 2.7 higher on trees with the largest and smallest RHW, respectively. More complex plant architectures favored species diversity for galling insects and their natural enemies. The competition among four galling insect species for space and feeding and the evidence of "prudence strategy" were, for the first time, observed for galling insects in the Brazilian Cerrado biome.


Asunto(s)
Biodiversidad , Ericales/clasificación , Ericales/parasitología , Interacciones Huésped-Parásitos , Insectos , Árboles , Animales , Brasil , Ecosistema , Cadena Alimentaria , Herbivoria , Hojas de la Planta/parasitología , Estaciones del Año
5.
São Paulo; s.n; s.n; 2016. 94 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: biblio-846667

RESUMEN

O óleo da amêndoa de pequi (Caryocar brasiliense Camb.) é considerado um coproduto do fruto, consumido na região do Cerrado, bioma brasileiro. Ele é fundamental para agregar valor e ampliar a utilização deste fruto regional a outros setores produtivos comerciais. Relatos na literatura apontam que o óleo possui capacidade antioxidante e efeitos benéficos sobre doenças inflamatórias, que estão associados à presença de ácidos graxos insaturados e fitoquímicos em sua composição química. Por outro lado, o tetracloreto de carbono (CCl4) é uma potente hepatotoxina, capaz de gerar radicais livres que levam ao estresse oxidativo e à inflamação. Nesse contexto, o objetivo do presente estudo foi caracterizar os óleos da amêndoa de pequi obtidos artesanalmente e por prensagem a frio e verificar o efeito de seus constituintes graxos e bioativos sobre parâmetros oxidativos e inflamatórios de ratos submetidos à toxicidade aguda induzida por tetracloreto de carbono. Inicialmente, foram investigados os parâmetros de qualidade dos óleos, bem como o perfil de ácidos graxos, teores de compostos bioativos, capacidade antioxidante e estabilidade termo-oxidativa. Os óleos da amêndoa de pequi apresentaram boa qualidade e resistência termo-oxidativa e mostraram-se ricos em ácido graxo oleico, além de possuírem compostos com propriedades antioxidantes, como fenólicos, carotenoides, tocoferóis e fitosteróis. Posteriormente, o efeito do tratamento por 22 dias com óleos da amêndoa de pequi artesanal ou prensado a frio (3 mL/kg) sobre a toxicidade aguda induzida pelo CCl4 em ratos "Wistar" machos foi avaliado. Para tal, foram determinados marcadores bioquímicos séricos, perfil lipídico, peroxidação lipídica, marcadores do sistema de defesa antioxidante e detoxificante, além de parâmetros inflamatórios do tecido hepático. De maneira geral, verificou-se que os óleos da amêndoa de pequi não minimizaram as alterações hepáticas induzidas pelo CCl4, evidenciadas pelas enzimas marcadoras do dano hepático e por parâmetros inflamatórios, no entanto os animais tratados com o óleo prensado a frio aumentaram sua capacidade antioxidante


The pequi (Caryocar brasiliense Camb.) almond oil is considered a by-product of the fruit, consumed in the Brazilian savannah region. It is essential to add value and increase the use this regional fruit to other commercial productive sectors. The pequi almond oil has been reported to possess antioxidant capacity and beneficial effect on inflammatory diseases due its chemical composition in unsaturated fatty compounds and phytochemicals. On the other hand, the carbon tetrachloride (CCl4) is a potent hepatotoxin that is capable of generating free radicals and lead to oxidative stress and inflammation. In this context, the aim of this study was to characterize the pequi almond oils obtained by handmade and cold-press process and verify the effect of their fatty acids and bioactive constituents on oxidative and inflammatory parameters in rats submitted to carbon tetrachloride-induced acute toxicity. Initially, quality parameters, chemical composition and thermo-oxidative stability of the oils were investigated. The pequi almond oils showed good quality and thermo-oxidative resistance and shown to be rich in oleic fatty acid, besides the presence of compounds with antioxidant properties, such as phenolics, carotenoids, tocopherols and phytosterols. Subsequently, the effect of the oils (3 mL/kg) treatment for 22 days on acute toxicity induced by CCl4 in male Wistar rats was evaluated. The serum biochemical markers levels, lipid profile, lipid peroxidation, markers of antioxidant defense and detoxication and inflammatory parameters in liver tissue were determined. In general, it was found that the pequi almond oil not minimized liver alterations induced by CCl4, as evidenced by the liver function enzymes and the inflammatory parameters, however in animals which received the cold pressed oil was increased antioxidant capacity


Asunto(s)
Animales , Masculino , Ratas , Intoxicación por Tetracloruro de Carbono , Biomarcadores/química , Estrés Oxidativo , Ericales/clasificación , /prevención & control , Aceites Volátiles/efectos adversos , Tetracloruro de Carbono/administración & dosificación , Peroxidación de Lípido , Cromatografía de Gases/métodos
6.
Rev. bras. plantas med ; 17(4,supl.2): 875-880, 2015. graf
Artículo en Portugués | LILACS | ID: lil-771157

RESUMEN

RESUMO O objetivo deste estudo foi analisar o efeito do óleo de pequi no processo cicatricial de lesões cutâneas em ratos. A pesquisa foi iniciada após a provação da CEUA- FACID sob o nº de protocolo 005/12 e obedeceu aos princípios éticos da experimentação animal de acordo com a Lei Federal nº 11.794/2008. Foram utilizados 20 ratos machos, Wistar (Rattusnorvegicus), peso corpóreo de 300-350g, divididos aleatoriamente em dois grupos iguais: GI- controle (C); GII- tratado com óleo de pequi (T). Cada grupo foi dividido em dois subgrupos, de cinco animais cada, conforme os tempos experimentais estudados de 7(A) e 14(B) dias. Após anestesia e antissepsia foi produzida cirurgicamente ferida circular de 2,5 cm de diâmetro na região dorso lombar do animal. Os animais do Grupo II foram tratados com aplicação tópica diária de 1 ml do óleo de pequi, respeitando os tempos experimentais descritos. Concomitante à mensuração da área da lesão, os ratos foram eutanasiados para realização do processamento histológico e análise do percentual de regressão das lesões. No grupo GII nos diferentes tempos experimentais de 7 e 14 dias foi observado maior percentual de regressão das lesões em relação ao GI (p < 0,05). A partir da análise histológica foi possível detectar que no GII houve menor número de células inflamatórias e maior número de fibroblastos em relação ao GI nos diferentes tempos experimentais (p < 0,001). Conclui-se que o uso do óleo de pequi apresentou influência positiva no processo de reparo de lesões cutâneas em ratos, por promover maior velocidade do reparo tecidual, fato evidenciado pelo fechamento mais rápido das feridas e observação de características inflamatórias reduzidas no grupo tratado em relação ao grupo controle, sugerindo que a inflamação pode já ter regredido no grupo tratado.


ABSTRACT The aim of this study was to analyze the effect of pequi oil in the healing process of skin lesions in rats. The research was initiated after the ordeal of CEUA- FACID with protocol No. 005/12 and following the ethical principles of animal experimentation according to the Federal Law No. 11,794 / 2008. 20 Wistar rats were used (Rattus norvegicus), with body weight ranging from 300-350g. They were randomly divided into two groups: GI control (C) and GII treated with pequi oil (T). Each group was divided into two subgroups of five animals each, according to the experimental study of 7 days (A) and 14 (B) days. After anesthesia and antisepsis, a circular wound of 2.5 cm of diameter was surgically inflicted in the lumbar dorsal region of the animal. The animals in Group II were treated with daily topical application of 1 ml of pequi oil, respecting the described experimental times. Concomitantly with the measurement of the injury area, the rats were euthanized so that a histological processing and a regression analysis of the percentage of injuries could be performed. In GII, at different experimental times of 7 and 14 days, there were a higher percentage of lesions regression compared to GI (p <0.05). From the histological examination it was possible to detect that, at GII, there were a lower number of inflammatory cells and increased number of fibroblasts compared to IM at different time of the trial (P <0.001). It is concluded that the use of pequi oil presented positive influence on the healing process of skin lesions in rats by promoting quicker tissue repair, as indicated by the faster closure of the wounds and the observation of reduced inflammatory characteristics in the group treated compared to the control group, suggesting that the inflammation could have already receded in the treated group.


Asunto(s)
Masculino , Ratas , Ratas/clasificación , Cicatrización de Heridas , Aceites Volátiles/análisis , Ericales/clasificación , Lesiones por Desenguantamiento/clasificación , Heridas y Lesiones/diagnóstico , Inflamación/diagnóstico
7.
An. acad. bras. ciênc ; 82(3): 779-789, Sept. 2010. ilus, mapas, tab
Artículo en Inglés | LILACS | ID: lil-556812

RESUMEN

Caryocar brasiliense (pequi), is one of the main species at the biome of the Brazilian savannah due to its use in culinary, popular medicine, industry in general, and iron and steel industry. At São José do Xingu (MT), a tree of C. brasiliense without thorn at the endocarp was found, which enables the improvement of C. brasiliense not only for consumption but also to the high appreciation it already has. To detect the existing differences between the pequi with and without the thorn at the endocarp, RADP markers were used. The generated polymorphisms were cloned and sequenced in order to identify the sequences that are responsible for the fenotypical alteration. It was observed that the pequi without thorn is genetically isolated from the other populations of pequi with thorn at the endocarp, proving that this characteristic is related to the genetic divergence of the species. Analysis in BLASTn evidenced the similarity of the Dof1 genes of Zea mays to its gene of phosphinotricin acetyl transferase. In the analysis of BLASTx, the similarity was verified to the proteins responsible for the deficiency in ferric reductase 4, and catalase.


Pequi, Caryocar brasiliense, é uma das espécies de destaqueno bioma do cerrado brasileiro, devido a sua utilização na medicina, na culinária popular, indústria em geral, e na do ferro e do aço. Na região de São José do Xingu (MT), uma árvore de pequi sem espinho no endocarpo foi encontrado e isso permite melhorar pequi não só para o consumo, aproveitando a alta apreciação que já possui. Para detectar as diferenças existentes entre o genoma de pequi com e sem espinho no endocarpo, marcadores moleculares RAPD foram utilizados. Os polimorfismos gerados foram clonados e sequenciados, a fim de identificar as sequências responsáveis pela alteração fenotípica. Observou-se que o pequi sem espinho é geneticamente isolado de outras populações de pequi com espinho no endocarpo, provando que essa característica está relacionada com a divergência genética da espécie. Análise em Blastn evidenciou a similaridade dos genes Dof1 e com o gene da fosfinotricina-acetiltransferase de Z. mays. Na análise da BLASTx, a similaridade foi verificada com as proteínas responsáveis pela deficiência de ferro 4 redutase e catalase.


Asunto(s)
ADN de Plantas/genética , Genoma de Planta/genética , Polimorfismo Genético/genética , Ericales/genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Ericales/anatomía & histología , Ericales/clasificación
8.
An Acad Bras Cienc ; 82(3): 779-89, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21562705

RESUMEN

Caryocar brasiliense (pequi), is one of the main species at the biome of the Brazilian savannah due to its use in culinary, popular medicine, industry in general, and iron and steel industry. At São José do Xingu (MT), a tree of C. brasiliense without thorn at the endocarp was found, which enables the improvement of C. brasiliense not only for consumption but also to the high appreciation it already has. To detect the existing differences between the pequi with and without the thorn at the endocarp, RADP markers were used. The generated polymorphisms were cloned and sequenced in order to identify the sequences that are responsible for the fenotypical alteration. It was observed that the pequi without thorn is genetically isolated from the other populations of pequi with thorn at the endocarp, proving that this characteristic is related to the genetic divergence of the species. Analysis in BLASTn evidenced the similarity of the Dof1 genes of Zea mays to its gene of phosphinotricin acetyl transferase. In the analysis of BLASTx, the similarity was verified to the proteins responsible for the deficiency in ferric reductase 4, and catalase.


Asunto(s)
ADN de Plantas/genética , Ericales/genética , Genoma de Planta/genética , Polimorfismo Genético/genética , Ericales/anatomía & histología , Ericales/clasificación , Técnica del ADN Polimorfo Amplificado Aleatorio
9.
São Paulo; s.n; s.n; 2008. 182 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: biblio-837321

RESUMEN

O estresse oxidativo produzido no organismo relaciona-se com o aparecimento e/ou desenvolvimento de uma série de doenças crônico-não transmissíveis. Os compostos fenólicos, presentes nos vegetais, são capazes de neutralizar as estruturas radicalares; diminuindo, portanto, o risco de surgimento de patologias a elas associadas. O objetivo do presente trabalho foi avaliar a atividade antioxidante do fruto e da amêndoa do pequi e a participação desta atividade na prevenção do processo oxidativo em ratos. Foram obtidos, de forma seqüencial, os extratos etéreo, alcoólico e aquoso, bem como as frações de ácidos fenólicos livres (AFL), esterificadas solúveis (AFS) e insolúveis (AFI) da polpa e da amêndoa do pequi. Todos os extratos e frações foram avaliados quanto à atividade antioxidante in vitro pelos ensaios de co-oxidação do ß-caroteno/ácido linoléico, DPPH (radical 1,1-diphenil-2-picrilhydrazil), ABTS (radical 2,2'azinobis-(3-ethylbenzthiazoline-6-sulfonic acid), ORAC (Capacidade de Absorção de Radicais Oxigênio) e Rancimat; e apresentaram expressiva atividade antioxidante. Entre os extratos, o aquoso da polpa apresentou maior atividade; entre as frações, a AFL da polpa se destacou nos ensaios ß-caroteno/ácido linoléico, DPPH e ABTS. Os extratos e frações foram também avaliados quanto à composição em ácidos fenólicos, por HPLC. Encontraram-se os ácidos elágico, gálico, 4-OH benzóico, p-cumárico e procianidina B2. O ácido elágico esteve presente em todos os extratos e/ou frações, sempre em maior concentração; a procianidina B2, apenas no extrato aquoso da amêndoa. Na avaliação da atividade antioxidante in vivo, em ratos normais, foi administrado, por gavagem, extrato aquoso (100 e 300 mg/kg v.o.) e AFL (40 e 100 mg/kg v.o.) obtidos da polpa do pequi. Evidenciaram-se redução da lipoperoxidação e elevação da atividade das enzimas antioxidantes catalase (CAT), superóxido dismutase (SOD), glutationa peroxidase (GPx) e glutationa redutase (GR) no cérebro e no fígado dos animais que receberam o extrato aquoso a 300 mg/kg e a fração AFL a 100 mg/kg. Isso demonstra que o pequi possui propriedades antioxidantes tanto in vitro como in vivo


The oxidative stress produced in live organisms is related to the appearance and/or development of a series of non-transmissible chronic diseases. Phenolic compounds present in vegetables are able to neutralize these substances, thus reducing the risk of development of free radicals associated to pathologies. The aim of this work was to evaluate the antioxidant activity in the pulp and almond of the pequi fruit and its effects in preventing the oxidative process in rats. Extracts were obtained by means of sequential extraction in which solvents with different polarities (ether, ethanol and water) were used, as well as free phenolic acid fraction (and) soluble esters and insolublebound compounds from the pulp and almond of the pequi. The total antioxidant capacity was estimated through the following methods: ß-carotene bleaching, DPPH (1,1- diphenyl-2-picrylhydrazyl radical), ABTS (2,2'azinobis-(3-ethylbenzthiazoline-6-sulfonic acid), oxygen radical absorbance capacity (ORAC), and Rancimat assays. All extracts and fractions of phenolic acids showed a significant antioxidant activity. Among the extracts, the pulp aqueous extract showed higher activities than the others. Free phenolic acids fraction from the pulp of the pequi was better compared to other fractions in ß-carotene bleaching, DPPH and ABTS assays. Phenolic acids composition was identified by HPLC. It was found ellagic, gallic, 4-Hydroxybenzoic, p-coumaric and procyanidin B2 acid being ellagic acid presents at larger amounts in all extracts and fractions, whereas procyanidin B2 was found only in the aqueous extract of the almond from pequi. For evaluating the antioxidant activity in vivo, aqueous extract (100 and 300 mg/kg b.w.) and free phenolic acids (40 and 100 mg/kg b.w.) obtained from pequi pulp were administered in rats by oral gavage. It was observed a decrease in the levels of lipid peroxidation and an increased activity of antioxidant enzymes catalase (CAT), superoxide dismutade (SOD), glutathione peroxidase (GSHPx), and glutathione reductase (GSSGr) in the brain and liver of animals that received aqueous extract at 300 mg/kg b.w. and free phenolic acids fraction at 100 mg/kg, which demonstrate that pequi fruit has both in vitro and in vivo antioxidative properties


Asunto(s)
Animales , Masculino , Ratas , Ericales/clasificación , Compuestos Fenólicos/análisis , Antioxidantes/farmacología , Productos Biológicos/análisis , Valor Nutritivo
10.
J Plant Res ; 119(5): 553-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16924562

RESUMEN

Genetic differentiation was investigated among 54 Indonesian species of Dipterocarpaceae, a dominant tree family in Asian tropical rainforests, using amplified fragment length polymorphism markers. The tree developed from the resultant unweighted pair group method using arithmetic averages clearly separated all investigated dipterocarps into two major groups that corresponded to tribe Dipterocarpeae and tribe Shoreae, respectively. These results are in accordance with the topology of molecular phylogenetic trees derived from PCR-restriction fragment length polymorphism analysis of chloroplast DNA and generally support the traditional taxonomic assessments. The possibility of interspecific hybridization is also discussed.


Asunto(s)
Ericales/clasificación , Ericales/genética , Evolución Molecular , Filogenia , Polimorfismo Genético/genética
11.
Mol Ecol ; 12(1): 105-15, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12492881

RESUMEN

In this work we report on the phylogeography of the endangered tree species Caryocar brasiliense based on variability in two classes of maternally inherited chloroplast DNA sequences with different rates of molecular evolution. Eleven sequence haplotypes of a noncoding region between the genes trnT and trnF and 21 distinct 10-locus microsatellite haplotypes could be identified in a total of 160 individuals, collected in 10 widespread populations of C. brasiliense. An amova indicated that most of the variation can be attributed to differences among populations, both for DNA sequence (87.51%) and microsatellites (84.38%). Phylogeography based on a median-joining network analysis of the noncoding region showed a sharp difference from the analysis of microsatellite haplotypes. Nevertheless, both analyses indicated that multiple lineages may have contributed to the origin of C. brasiliense populations in Brazilian Cerrado. Incongruences in the microsatellite haplotypes network suggest that homoplasy, which emerged from recurrent and independent mutations, greatly influenced the evolution of the C. brasiliense chloroplast genome. We hypothesize that our results may show the outcome of the restriction of ancient relic populations to moist refugias during extended droughts coinciding with glaciation in the northern hemisphere. The subsequent spread to favourable areas throughout Central Brazil may have caused contact between different lineages during the interglacial periods. The extinction of megafauna dispersers in the last glaciation may have caused a restriction in seed movement and currently, gene flow has been occurring mainly by pollen movement.


Asunto(s)
ADN de Cloroplastos/análisis , Ericales/genética , Variación Genética , Brasil , Ericales/clasificación , Haplotipos , Repeticiones de Microsatélite , Filogenia , Análisis de Secuencia de ADN
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