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1.
Fitoterapia ; 135: 52-63, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30999023

RESUMO

Steroidal saponins, one of the most diverse groups of plant-derived natural products, elicit biological and pharmacological activities; however, the genes involved in their biosynthesis and the corresponding biosynthetic pathway in monocotyledon plants remain unclear. This study aimed to identify genes involved in the biosynthesis of steroidal saponins by performing a comparative analysis among transcriptomes of Paris polyphylla var. chinensis (PPC), Ypsilandra thibetica (YT), and Polygonatum kingianum (PK). De novo transcriptome assemblies generated 57,537, 140,420, and 151,773 unigenes from PPC, YT, and PK, respectively, of which 56.54, 47.81, and 44.30% were successfully annotated, respectively. Among the transcriptomes for PPC, YT, and PK, we identified 194, 169, and 131; 17, 14, and 26; and, 80, 122, and 113 unigenes corresponding to terpenoid backbone biosynthesis; sesquiterpenoid and triterpenoid biosynthesis; and, steroid biosynthesis pathways, respectively. These genes are putatively involved in the biosynthesis of cholesterol that is the primary precursor of steroidal saponins. Phylogenetic analyses indicated that lanosterol synthase may be exclusive to dicotyledon plant species, and the cytochrome P450 unigenes were closely related to clusters CYP90B1 and CYP734A1, which are UDP-glycosyltransferases unigenes homologous with the UGT73 family. Thus, unigenes of ß-glucosidase may be candidate genes for catalysis of later period modifications of the steroidal saponin skeleton. Our data provide evidence to support the hypothesis that monocotyledons biosynthesize steroidal saponins from cholesterol via the cycloartenol pathway.


Assuntos
Liliaceae/genética , Melanthiaceae/genética , Fitosteróis/biossíntese , Polygonatum/genética , Saponinas/biossíntese , Transcriptoma , Vias Biossintéticas , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Liliaceae/química , Liliaceae/metabolismo , Melanthiaceae/química , Melanthiaceae/metabolismo , Estrutura Molecular , Filogenia , Fitosteróis/química , Fitosteróis/genética , Polygonatum/química , Polygonatum/metabolismo , Saponinas/química , Saponinas/genética , Triterpenos
2.
Am J Bot ; 106(3): 477-488, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30901490

RESUMO

PREMISE OF THE STUDY: Climate cycles of the Quaternary have impacted plants at a global scale, leaving behind a complex genetic legacy. Species of the northern Rocky Mountains of North America were exposed to more uniform glacial patterns than the central and southern ranges, where synergistic relationships between temperature and precipitation caused differences in the timing and extent of glacier onset. We examined the genetic impacts of climate oscillations on Calochortus gunnisonii (Liliaceae) in the central and southern Rocky Mountains. METHODS: Populations were sampled from disjunct mountain ranges across the basins of Wyoming and northern and central Colorado. Allelic data from nuclear microsatellites and plastid sequences (trnV-ndhC, petA-psbJ, and rpl16) were used to examine patterns of genetic structure between and among populations along the southern Rocky Mountain corridor. KEY RESULTS: We infer considerable population structure concordant with mountain range of origin. Clustering analysis supports separate north and south genetic clusters on either side of major basins in Wyoming, suggesting that populations were maintained in two distinct refugia. Additionally, populations within the Sierra Madre Range of southern Wyoming show localized, divergent genetic signal indicative of a third potential glacial refugium. By contrast, recent genetic admixture is observed in the Laramie, Medicine Bow, and Front ranges, where population expansion from glacial refugia has likely occurred. CONCLUSIONS: We conclude that during climate cycles of the Quaternary, C. gunnisonii experienced periods of population expansion and reduction, habitat fragmentation, isolation in three or more refugia, and admixture mirroring genetic impacts of other southern Rocky Mountains organisms.


Assuntos
Mudança Climática , Variação Genética , Liliaceae/genética , Colorado , Marcadores Genéticos , Refúgio , Wyoming
3.
Ann Bot ; 122(7): 1245-1262, 2018 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-30084909

RESUMO

Background and Aims: The role played by the Qinghai-Tibet Plateau (QTP) in the organismal diversification and biogeography of plants in the Northern Hemisphere has attracted much attention from evolutionary biologists. Here we use tribe Lilieae (Liliaceae), including primarily temperate and alpine lineages with disjunct distributions in the North Temperate Zone, as a case study to shed light upon these processes. Methods: Using 191 taxa (five outgroup taxa) comprising more than 60 % of extant Lilieae species across the entire geographical range, we analyse phylogenetic relationships based on three plastid markers (matK, rbcL, rpl16) and nuclear ITS. Divergence time estimation and ancestral range reconstruction were further inferred. Key Results: The results support a monophyletic Lilieae divided into four clades. Lilium is nested within Fritillaria, which is paraphyletic and partitioned into two clades, New World and Old World, in the chloroplast DNA (cpDNA) analysis. Incongruences between the ITS and cpDNA trees may be explained by divergent ITS paralogues and hybridization. Lilieae originated around 40-49 (28-67) Mya and probably diversified in the QTP region with four major clades that were established during the Oligocene and the Early Miocene. Uplift of the QTP and climatic changes probably drove early diversification of Lilieae in the QTP region. A rapid radiation occurred during the Late Miocene and the Pleistocene, coinciding temporally with recent orogenic process in the QTP region and climatic oscillations. Several lineages dispersed out of the QTP. Conclusions: Lineage persistence and explosive radiation were important processes for establishing high species diversity of Lilieae in the QTP region. Both long-distance dispersal and migration across Beringia probably contributed to the modern distribution range of Lilieae. Our study shows that biotic interchanges between the QTP region and Irano-Turanian region and the Mediterranean Basin were bi-directional, suggesting the latter was a secondary centre of diversity.


Assuntos
Biodiversidade , Liliaceae/classificação , Liliaceae/fisiologia , Filogenia , Dispersão Vegetal , Evolução Biológica , DNA de Cloroplastos/análise , Liliaceae/genética , Filogeografia
4.
PLoS One ; 13(1): e0190520, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300767

RESUMO

The so-called "Baekdudaegan" (BDDG), a mountain range that stretches along the Korean Peninsula, has been recently proposed as a major "southern" glacial refugium for boreal or temperate plant species based on palaeoecological and, especially, genetic data. Genetic studies comparing genetic variation between population occurring on the BDDG and more northern ones (i.e. in NE China and/or in Russian Far East) are, however, still too few to draw firm conclusions on the role of the BDDG as a refugium and a source for possible northward post-glacial recolonizations. In order to fill this gap, we selected a boreal/temperate herb, Lilium cernuum, and compared levels of allozyme-based genetic diversity of five populations from NE China with five populations from South Korea (home of its hypothesized refuge areas). As a complementary tool, we used the maximum entropy algorithm implemented in MaxEnt to infer the species' potential distribution for the present time, which was projected to different past climate scenarios for the Last Glacial Maximum (LGM). Permutation tests revealed that Korean populations harbored significantly higher levels of within-population genetic variation than those from NE China (expected heterozygosity = 0.173 vs. 0.095, respectively). Our results suggest that the lowered levels of genetic diversity in NE Chinese populations might be due to founder effects associated with post-glacial migration from southern regions. Congruent with genetic data, past distribution models showed higher probability of occurrence in southern ranges than in northern ones during the LGM. In addition, a positive correlation was detected between the expected heterozygosity and environmental LGM suitability. From a conservation perspective, our results further suggest that the southern populations in South Korea may be particularly worthy of protection.


Assuntos
Variação Genética , Liliaceae/genética , Algoritmos , Ásia , Fósseis
5.
BMC Genomics ; 19(Suppl 10): 878, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30598104

RESUMO

BACKGROUND: Species of Paris Sect. Marmorata are valuable medicinal plants to synthesize steroidal saponins with effective pharmacological therapy. However, the wild resources of the species are threatened by plundering exploitation before the molecular genetics studies uncover the genomes and evolutionary significance. Thus, the availability of complete chloroplast genome sequences of Sect. Marmorata is necessary and crucial to the understanding the plastome evolution of this section and facilitating future population genetics studies. Here, we determined chloroplast genomes of Sect. Marmorata, and conducted the whole chloroplast genome comparison. RESULTS: This study presented detailed sequences and structural variations of chloroplast genomes of Sect. Marmorata. Over 40 large repeats and approximately 130 simple sequence repeats as well as a group of genomic hotspots were detected. Inverted repeat contraction of this section was inferred via comparing the chloroplast genomes with the one of P. verticillata. Additionally, almost all the plastid protein coding genes were found to prefer ending with A/U. Mutation bias and selection pressure predominately shaped the codon bias of most genes. And most of the genes underwent purifying selection, whereas photosynthetic genes experienced a relatively relaxed purifying selection. CONCLUSIONS: Repeat sequences and hotspot regions can be scanned to detect the intraspecific and interspecific variability, and selected to infer the phylogenetic relationships of Sect. Marmorata and other species in subgenus Daiswa. Mutation and natural selection were the main forces to drive the codon bias pattern of most plastid protein coding genes. Therefore, this study enhances the understanding about evolution of Sect. Marmorata from the chloroplast genome, and provide genomic insights into genetic analyses of Sect. Marmorata.


Assuntos
Evolução Molecular , Genoma de Cloroplastos/genética , Liliaceae/genética , Sequências Repetitivas de Ácido Nucleico/genética , Códon/genética , Genes de Cloroplastos/genética , Genômica , Filogenia
6.
Int J Mol Sci ; 18(1)2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-28117746

RESUMO

Long dormancy period of seeds limits the large-scale artificial cultivation of the scarce Paris polyphylla var. yunnanensis, an important traditional Chinese medicine. Characterizing miRNAs and their targets is crucial to understanding the role of miRNAs during seed dormancy in this species. Considering the limited genome information of this species, we first sequenced and assembled the transcriptome data of dormant seeds and their seed coats as the reference genome. A total of 146,671 unigenes with an average length of 923 bp were identified and showed functional diversity based on different annotation methods. Two small RNA libraries from respective seeds and seed coats were sequenced and the combining data indicates that 263 conserved miRNAs belonging to at least 83 families and 768 novel miRNAs in 1174 transcripts were found. The annotations of the predicted putative targets of miRNAs suggest that these miRNAs were mainly involved in the cell, metabolism and genetic information processing by direct and indirect regulation patterns in dormant seeds of P. polyphylla var. yunnanensis. Therefore, we provide the first known miRNA profiles and their targets, which will assist with further study of the molecular mechanism of seed dormancy in P. polyphylla var. yunnanensis.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Liliaceae/genética , MicroRNAs/genética , Transcriptoma/genética , Sequência Conservada/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Anotação de Sequência Molecular , RNA de Plantas/genética , RNA de Plantas/metabolismo , Sementes/genética , Análise de Sequência de RNA
7.
Ann Bot ; 119(1): 59-72, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27941092

RESUMO

BACKGROUND AND AIMS: The patterns of evolutionary assembly in the Sino-Japanese floristic region (SJFR) remain largely unknown due to a lack of integrative multidimensional studies throughout the region. To address this issue, we elucidated the evolutionary history of Cardiocrinum (Liliaceae), a genus containing four taxa distributed across the SJFR. METHODS: Fifty-four populations were sampled throughout the geographical range of Cardiocrinum to assess genetic structure, analyse phylogenetic relationships and reconstruct ancestral area based on six chloroplast DNA (cpDNA) fragments and three low copy nuclear genes (LCNG). Ecological niche modelling was used to examine the potential range shifts of Cardiocrinum in response to climatic change. KEY RESULTS: The molecular data showed high genetic similarity in the cpDNA (98·37 %) and LCNG (94·53 %) sequences. The biogeographical analyses revealed that the ancestor of Cardiocrinum diversified during the late Miocene (approx. 7·32 Mya) in Central China. The ancestor of the C. giganteum lineage dispersed westward to the Himalayas and south-west China with the split between C. giganteum and C. giganteum var. yunnanense occurring around 4·11 Mya consistent with the period of orogeny of the Hengduan Mountains. Some populations of the C. cathayanum lineage dispersed eastward to south Japan via the land bridge approx. 4·97 Mya, providing opportunities for allopatric speciation of C. cordatum The predicted suitable habitats of Cardiocrinum have become smaller and more fragmented since the Last Glacial Maximum. CONCLUSIONS: Our study provides evidence of a biogeographical pattern of dispersal from Central China to the Himalayas in the west and Japan in the east for genera distributed across the SJFR, and highlights that the orogeny of the Hengduan Mountains and fluctuations of the sea level of the East China Sea played important roles in promoting species divergence.


Assuntos
Liliaceae/genética , Evolução Biológica , China , DNA de Plantas/genética , Ecossistema , Variação Genética/genética , Japão , Filogenia , Filogeografia , Análise de Sequência de DNA
8.
Sci Rep ; 6: 24549, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27079267

RESUMO

B class MADS-box genes play important roles in petal and stamen development. Some monocotyledonous species, including liliaceous ones, produce flowers with petaloid tepals in whorls 1 and 2. A modified ABCE model has been proposed to explain the molecular mechanism of development of two-layered petaloid tepals. However, direct evidence for this modified ABCE model has not been reported to date. To clarify the molecular mechanism determining the organ identity of two-layered petaloid tepals, we used chimeric repressor gene-silencing technology (CRES-T) to examine the suppression of B function in the liliaceous ornamental Tricyrtis sp. Transgenic plants with suppressed B class genes produced sepaloid tepals in whorls 1 and 2 instead of the petaloid tepals as expected. In addition, the stamens of transgenic plants converted into pistil-like organs with ovule- and stigma-like structures. This report is the first to describe the successful suppression of B function in monocotyledonous species with two-layered petaloid tepals, and the results strongly support the modified ABCE model.


Assuntos
Genes de Plantas , Liliaceae/genética , Modelos Genéticos , Flores , Regulação da Expressão Gênica de Plantas , Microscopia Eletrônica de Varredura , Filogenia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real
9.
PLoS One ; 11(3): e0152455, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27011209

RESUMO

We use chloroplast DNA sequencing to examine aspects of the pre-European Maori cultivation of an endemic New Zealand root crop, Arthropodium cirratum (rengarenga). Researching the early stages of domestication is not possible for the majority of crops, because their cultivation began many thousands of years ago and/or they have been substantially altered by modern breeding methods. We found high levels of genetic variation and structuring characterised the natural distribution of A. cirratum, while the translocated populations only retained low levels of this diversity, indicating a strong bottleneck even at the early stages of this species' cultivation. The high structuring detected at four chloroplast loci within the natural A. cirratum range enabled the putative source(s) of the translocated populations to be identified as most likely located in the eastern Bay of Plenty/East Cape region. The high structuring within A. cirratum also has implications for the conservation of genetic diversity within this species, which has undergone recent declines in both its natural and translocated ranges.


Assuntos
DNA de Cloroplastos/genética , Liliaceae/genética , Plantas Medicinais/genética , DNA de Plantas/genética , Variação Genética , Geografia , Haplótipos , Nova Zelândia , Nucleotídeos/genética , Filogeografia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Genetica ; 144(2): 157-66, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26869260

RESUMO

The genera Nothoscordum and Ipheion (Allioideae, Amaryllidaceae) are cytologically characterized by a dysploid series with variable numbers of metacentric and acrocentric chromosomes typical of karyotypes rearranged by Robertsonian translocations (RT). Since they have large chromosomes, low diploid numbers, and possess two telomeric motifs [the vertebrate-type (TTAGGG) n and the Arabidopsis-type (TTTAGGG) n ] they are suitable for investigating the occurrence and possible role of interstitial telomeric sites (ITS) associated with RT. We analyzed the distributions of telomeric sites in 12 species of Nothoscordum and Ipheion and found that both telomeric probes colocalized in all chromosome termini. Cloning and sequencing PCR products obtained using both telomeric primers simultaneously revealed long stretches of (TTAGGG) n and (TTTAGGG) n sequences together with degenerated telomeric sequences. Most acrocentric chromosomes have a 45S rDNA site at the terminal region of the short arms adjacent to the most distal telomeric sites. Telomeric signals were found at all chromosome ends, but ITS were also detected in a few proximal and subterminal regions in some Nothoscordum species. Although RT are common in this group of plants, our findings suggest that proximal positioning of telomeric motifs are not necessarily related to that kind of rearrangement. Rather, transposition of telomeric sequences followed by amplification, could better explain the presence of (TTAGGG) n and (TTTAGGG) n repeats at those sites. Furthermore, a few small interstitial sites found in some Nothoscordum species indicate that dispersion of these sequences was not restricted to the proximal region.


Assuntos
Cromossomos de Plantas/genética , Liliaceae/genética , Telômero/genética , Translocação Genética , Sequência de Bases , DNA de Plantas/genética , Hibridização in Situ Fluorescente , Cariótipo , Dados de Sequência Molecular , RNA Ribossômico/genética , Análise de Sequência de DNA
11.
Artigo em Inglês | MEDLINE | ID: mdl-25186113

RESUMO

The complete chloroplast (cp) genome sequence of Eustrephus latifolius was firstly determined in subfamily Lomandriodeae of family Asparagaceae. It was 159,736 bp and contained a large single copy region (82,403 bp) and a small single copy region (13,607 bp) which were separated by two inverted repeat regions (31,863 bp). In total, 132 genes were identified and they were consisted of 83 coding genes, 8 rRNA genes, 38 tRNA genes, 3 pseudogenes. rpl23 and clpP were pseudogenes due to sequence deletions. Among 23 genes containing introns, rps12 and ycf3 contained two introns and the rest had just one intron. The intact ycf68 was identified within an intron of trnI-GAU. The amino acid sequence was almost identical with Phoenix dactylifera in Aracales. Ycf1 of E. latifolius was completely located in IR. It was similar to cp genome structure of Lemna minor, Spirodela polyrhiza, Wolffiella lingulata, Wolffia australiana in Alismatales.


Assuntos
DNA de Cloroplastos/química , Genoma de Cloroplastos , Liliaceae/genética , Composição de Bases , Mapeamento Cromossômico , Dados de Sequência Molecular , Análise de Sequência de DNA
12.
Funct Integr Genomics ; 16(1): 37-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26458557

RESUMO

Chlorophytum borivilianum is an important species of liliaceae family, owing to its vital medicinal properties. Plant roots are used for aphrodisiac, adaptogen, anti-aging, health-restorative and health-promoting purposes. Saponins, are considered to be the principal bioactive components responsible for the wide variety of pharmacological properties of this plant. In the present study, we have performed de novo root transcriptome sequencing of C. borivilianum using Illumina Hiseq 2000 platform, to gain molecular insight into saponins biosynthesis. A total of 33,963,356 high-quality reads were obtained after quality filtration. Sequences were assembled using various programs which generated 97,344 transcripts with a size range of 100-5,216 bp and N50 value of 342. Data was analyzed against non-redundant proteins, gene ontology (GO), and enzyme commission (EC) databases. All the genes involved in saponins biosynthesis along with five full-length genes namely farnesyl pyrophosphate synthase, cycloartenol synthase, ß-amyrin synthase, cytochrome p450, and sterol-3-glucosyltransferase were identified. Read per exon kilobase per million (RPKM)-based comparative expression profiling was done to study the differential regulation of the genes. In silico expression analysis of seven selected genes of saponin biosynthetic pathway was validated by qRT-PCR.


Assuntos
Genes de Plantas , Liliaceae/genética , Saponinas/biossíntese , Transcriptoma , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Geraniltranstransferase/genética , Geraniltranstransferase/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Liliaceae/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Saponinas/genética
13.
Mol Phylogenet Evol ; 95: 79-93, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26639102

RESUMO

The disjunct distribution of the subgenus Anguinum of the genus Allium makes it a good candidate to test models of Northern hemisphere biogeography. Here we conduct phylogenetic analysis with the nuclear marker ITS and three different chloroplast markers (rps16 intron, rbcL-atpB spacer, rpl32-trnL spacer). Divergence time estimations (Beast) relying on published ITS substitution rates and ancestral range reconstructions were calculated to elucidate the biogeographical history of the subgenus. Additionally we compiled distribution maps for all species with data taken from the literature, herbariums and data from field observations. The main radiation of the subgenus took place in the last one million years and is still going on. They have their origins in the mid Miocene in East Asia and were highly influenced by the climate fluctuations in the Pliocene/Pleistocene period. Conflicting tree topologies between nuclear and cpDNA markers of Allium tricoccum Solander indicate that the species is of hybridogenous origin. Cloning the ITS sequence revealed the parental copies and confirmed our conclusion. One originated from the Eurasian and the other from the East Asian clade. We were able to show that it reached North America most likely via the Beringia around 2.5mya (95% HPD of 0.35-5.26mya). Our data suggest that Allium victorialis L. is only distributed in mountain pastures in Europe as it forms a well-supported clade in the ITS tree. In the analysis of the molecular markers we found two distinct types of Allium ochotense Prokh. and we suggest splitting the species based on Prokhanov's (1930) proposal. Taxonomical remarks and an identification key to all species of the subgenus Anguinum is provided.


Assuntos
Allium/classificação , Allium/genética , DNA de Cloroplastos/genética , Europa (Continente) , Extremo Oriente , Especiação Genética , Liliaceae/classificação , Liliaceae/genética , América do Norte , Filogenia , Filogeografia , Análise de Sequência de DNA
14.
New Phytol ; 210(2): 709-16, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26595257

RESUMO

The factors driving genome size evolution in Liliaceae were examined. In particular, we investigated whether species with larger genomes are confined to less stressful environments with a longer vegetative season. We tested our hypotheses by correlating the genome size with other plant traits and environmental variables. To determine the adaptive nature of the genome size, we also compared the performances of Brownian motion (BM) processes with those inferred by Ornstein-Uhlenbeck (OU) models of trait evolution. A positive correlation of genome size with plant size, mean temperature and habitat moisture and a negative correlation with altitude and precipitation seasonality were found. Models of trait evolution revealed a deviation from a drift process or BM. Instead, changes in genome size were significantly associated with precipitation regimes according to an OU process. Specifically, the evolutionary optima towards which the genome size evolves were higher for humid climates and lower for drier ones. Taken together, our results indicate that the genome size increase in Liliaceae is constrained by climate seasonality.


Assuntos
Clima , Ecossistema , Genoma de Planta , Liliaceae/genética , Modelos Genéticos , Característica Quantitativa Herdável , Estações do Ano , DNA de Plantas/metabolismo , Evolução Molecular , Tamanho do Genoma , Análise dos Mínimos Quadrados , Funções Verossimilhança , Filogenia , Chuva , Análise de Regressão
15.
Plant Sci ; 241: 266-76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26706077

RESUMO

The evolution of greenish sepals from petaloid outer tepals has occurred repeatedly in various lineages of non-grass monocots. Studies in distinct monocot species showed that the evolution of sepals could be explained by the ABC model; for example, the defect of B-class function in the outermost whorl was linked to the evolution of sepals. Here, floral MADS-box genes from three sepal-bearing monocotyledonous Trilliaceae species, Trillium camschatcense, Paris verticillata, and Kinugasa japonica were examined. Unexpectedly, expression of not only A- but also B-class genes was detected in the sepals of all three species. Although the E-class gene is generally expressed across all floral whorls, no expression was detected in sepals in the three species examined here. Overexpression of the E-class SEPALLATA3-like gene from T. camschatcense (TcamSEP) in Arabidopsis thaliana produced phenotypes identical to those reported for orthologs in other monocots. Additionally, yeast hybrid experiments indicated that TcamSEP could form a higher-order complex with an endogenous heterodimer of B-class APETALA3/DEFICIENS-like (TcamDEF) and PISTILLATA/GLOBOSA-like (TcamGLO) proteins. These results suggest a conserved role for Trilliaceae SEPALLATA3-like genes in functionalization of the B-class genes, and that a lack of SEPALLATA3-like gene expression in the outermost whorl may be related to the formation of greenish sepals.


Assuntos
Regulação da Expressão Gênica de Plantas , Liliaceae/genética , Proteínas de Domínio MADS/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Evolução Molecular , Flores/genética , Flores/crescimento & desenvolvimento , Liliaceae/crescimento & desenvolvimento , Liliaceae/metabolismo , Proteínas de Domínio MADS/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Trillium/genética , Trillium/crescimento & desenvolvimento , Trillium/metabolismo
16.
Indian J Exp Biol ; 53(6): 412-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26155682

RESUMO

In the present study, we explored the diversity of different accessions of Drimia indica and its relation to D. nagarjunae using phenotypic traits and molecular markers. Twenty populations of D. indica, from different parts of India, were compared with D. nagarjunae, an endangered medicinal plant collected from Andhra Pradesh, India. Two species showed appreciable phenotypic diversity in number of leaves, leaf indices, bulb circumference, bulb length and length of roots. The principal component analysis (PCA) performed on above 5 quantitative characters to determine relationship among populations, has distinguished D. nagarjunae from D. indica phenotypically. Genetic diversity was analysed using RAPD and ISSR primers which produced reproducible bands in 8 RAPD and 3 ISSR primers. A total of 89 amplicons were observed, of which 69 (77.53%) were polymorphic. Cluster diagram and phylogenetic linkage showed that D. nagarjunae formed a separate cluster, showing no similarity with any of the populations of D. indica. The molecular marker data correlated with PCA of phenotypic traits. Current investigations have demonstrated that the statistical approach for phenotypic characters and molecular markers analysis can be applied to study diversity in Drimia species.


Assuntos
Liliaceae/classificação , Análise por Conglomerados , Marcadores Genéticos/genética , Liliaceae/genética , Liliaceae/fisiologia , Fenótipo , Filogenia
17.
Evolution ; 69(9): 2262-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26194119

RESUMO

Geographic variation in floral morphology is often assumed to reflect geographic variation in pollinator communities and associated divergence in selective pressures. We studied populations of Nerine humilis (Amaryllidaceae) to assess whether geographic variation in floral form is the result of local adaptation to different pollinator communities. We first tested for associations between floral traits and visitor communities, and found that populations with similar floral morphologies were visited by similar insect communities. Mean style length in each population was also closely associated with the mean body length of the local visitor community. A reciprocal translocation experiment demonstrated that native phenotypes set more seed than translocated phenotypes. Single visitation experiments showed that native flowers received more pollen, and set more seed per visit, than introduced phenotypes in both populations. This suggests that the effectiveness of pollinator visits is determined by the degree of mechanical fit between flowers and visitors. We provide strong evidence that the observed among-population variation in floral traits is an adaptive response to geographic variation in the pollinator community.


Assuntos
Tamanho Corporal , Ecótipo , Flores/anatomia & histologia , Insetos/anatomia & histologia , Liliaceae/fisiologia , Polinização , Animais , Geografia , Liliaceae/anatomia & histologia , Liliaceae/genética , Fenótipo , Reprodução/fisiologia , África do Sul
18.
Mol Phylogenet Evol ; 92: 25-44, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26079131

RESUMO

In the most comprehensive study to date we explored the phylogeny and evolution of the genus Asparagus, with emphasis on the southern African species. We included 211 accessions, representing 77 (92%) of the southern African, 6 (17%) of the tropical African, 10 (56%) of the strictly European and 6 (9%) of the Eurasian species. We analyzed DNA sequences from three plastid regions (trnH-psbA, trnD-T, ndhF) and from the nuclear region phytochrome C (PHYC) with parsimony and maximum likelihood methods, and recovered a monophyletic Asparagus. The phylogeny conflicts with all previous infra-generic classifications. It has many strongly supported clades, corroborated by morphological characters, which may provide a basis for a revised taxonomy. Additionally, the phylogeny indicates that many of the current species delimitations are problematic. Using biogeographic analyses that account for phylogenetic uncertainty (S-DIVA) and take into account relative branch lengths (Lagrange) we confirm the origin of Asparagus in southern Africa, and find no evidence that the dispersal of Asparagus follow the Rand flora pattern. We find that all truly dioecious species of Asparagus share a common origin, but that sexual dimorphism has arisen independently several times.


Assuntos
Evolução Biológica , Liliaceae/anatomia & histologia , Liliaceae/classificação , Filogenia , África Austral , Ásia , Europa (Continente) , Flores , Funções Verossimilhança , Liliaceae/genética , Dados de Sequência Molecular , Filogeografia , Fitocromo/genética , Plastídeos/genética , Análise de Sequência de DNA
19.
Plant Cell Rep ; 34(9): 1499-513, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26104871

RESUMO

KEY MESSAGE: Oxidative stress and apoptosis-like programmed cell death, induced in part by H 2 O 2 , are two key factors that damage cells during plant cryopreservation. Their inhibition can improve cell viability. We hypothesized that oxidative stress and apoptosis-like event induced by ROS seriously impact plant cell viability during cryopreservation. This study documented changes in cell morphology and ultrastructure, and detected dynamic changes in ROS components (O 2 (·-) , H2O2 and OH·), antioxidant systems, and programmed cell death (PCD) events during embryonic callus cryopreservation of Agapanthus praecox. Plasmolysis, organelle ultrastructure changes, and increases in malondialdehyde (a membrane lipid peroxidation product) suggested that oxidative damage and PCD events occurred at several early cryopreservation steps. PCD events including autophagy, apoptosis-like, and necrosis also occurred at later stages of cryopreservation, and most were apoptosis. H2O2 is the most important ROS molecule mediating oxidative damage and affecting cell viability, and catalase and AsA-GSH cycle are involved in scavenging the intracellular H2O2 and protecting the cells against stress damage in the whole process. Gene expression studies verified changes of antioxidant system and PCD-related genes at the main steps of the cryopreservation process that correlated with improved cell viability. Reducing oxidative stress or inhibition of apoptosis-like event by deactivating proteases improved cryopreserved cell viability from 49.14 to 86.85 % and 89.91 %, respectively. These results verify our model of ROS-induced oxidative stress and apoptosis-like event in plant cryopreservation. This study provided a novel insight into cell stress response mechanisms in cryopreservation.


Assuntos
Apoptose/efeitos dos fármacos , Criopreservação , Liliaceae/citologia , Liliaceae/embriologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/toxicidade , Sementes/citologia , Antioxidantes/metabolismo , Autofagia/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Liliaceae/genética , Liliaceae/ultraestrutura , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sementes/efeitos dos fármacos , Sementes/ultraestrutura
20.
J Plant Res ; 128(5): 721-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26040419

RESUMO

Four Erythronium species have been traditionally recognised within Eurasia based on their disjunct distributions and the slight morphological divergence between them: E. dens-canis, E. caucasicum, E. sibiricum and E. japonicum. The range of E. sibiricum includes adjacent parts of southern Siberia, Kazakhstan, China and Mongolia in the Altai-Sayan mountain region. Despite several recently proposed taxa within the range of E. sibiricum (E. sajanense, E. sibiricum subsp. altaicum, E. sibiricum subsp. sulevii), this species has never been tested for genetic subdivisions. We here used nucleotide sequence variation in one nuclear (internal transcribed spacer) and two plastid (rpl32-trnL, rps15-ycf1) regions to test for genetic divisions within Siberian Erythronium and, in particular, to examine the phylogenetic position of E. sajanense. The plastid phylogeny revealed a basal polytomy among E. japonicum, E. sibiricum populations pertaining to E. sajanense and a third strongly supported lineage that includes E. dens-canis, E. caucasicum and the remainder of E. sibiricum, thus rendering Siberian Erythronium non-monophyletic. The nuclear topology agrees with the plastid one in recovering E. sajanense as a distinct lineage that is weakly supported as sister to E. japonicum. Topological incongruences exist between the plastid and nuclear phylogenies but these do not affect the taxonomic recognition of E. sajanense (endemic to the Western Sayan Mts.). This species is morphologically distinguishable on the basis of its subulate stamen filaments. Whereas nuclear phylogeny failed to resolve any genetic grouping within E. sibiricum s. str., plastid data recovered a deep (possibly phylogeographically meaningful) lineage from samples referred to as E. sibiricum subsp. altaicum.


Assuntos
DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Variação Genética , Liliaceae/genética , Dados de Sequência Molecular , Filogenia , Plastídeos/genética , Análise de Sequência de DNA , Sibéria
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