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1.
Am J Bot ; 105(11): 1888-1910, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30368769

RESUMO

PREMISE OF THE STUDY: We present the first plastome phylogeny encompassing all 77 monocot families, estimate branch support, and infer monocot-wide divergence times and rates of species diversification. METHODS: We conducted maximum likelihood analyses of phylogeny and BAMM studies of diversification rates based on 77 plastid genes across 545 monocots and 22 outgroups. We quantified how branch support and ascertainment vary with gene number, branch length, and branch depth. KEY RESULTS: Phylogenomic analyses shift the placement of 16 families in relation to earlier studies based on four plastid genes, add seven families, date the divergence between monocots and eudicots+Ceratophyllum at 136 Mya, successfully place all mycoheterotrophic taxa examined, and support recognizing Taccaceae and Thismiaceae as separate families and Arecales and Dasypogonales as separate orders. Only 45% of interfamilial divergences occurred after the Cretaceous. Net species diversification underwent four large-scale accelerations in PACMAD-BOP Poaceae, Asparagales sister to Doryanthaceae, Orchidoideae-Epidendroideae, and Araceae sister to Lemnoideae, each associated with specific ecological/morphological shifts. Branch ascertainment and support across monocots increase with gene number and branch length, and decrease with relative branch depth. Analysis of entire plastomes in Zingiberales quantifies the importance of non-coding regions in identifying and supporting short, deep branches. CONCLUSIONS: We provide the first resolved, well-supported monocot phylogeny and timeline spanning all families, and quantify the significant contribution of plastome-scale data to resolving short, deep branches. We outline a new functional model for the evolution of monocots and their diagnostic morphological traits from submersed aquatic ancestors, supported by convergent evolution of many of these traits in aquatic Hydatellaceae (Nymphaeales).


Assuntos
Especiação Genética , Genomas de Plastídeos , Magnoliopsida/genética , Filogenia , DNA Intergênico , Zingiberales/genética
2.
Mol Phylogenet Evol ; 128: 55-68, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30063997

RESUMO

Many cases of rapid evolutionary radiations in plant and animal lineages are known; however phylogenetic relationships among these lineages have been difficult to resolve by systematists. Increasing amounts of genomic data have been sequentially applied in an attempt to resolve these radiations, dissecting their evolutionary patterns into a series of bifurcating events. Here we explore one such rapid radiation in the tropical plant order Zingiberales (the bananas and relatives) which includes eight families, approximately 110 genera, and more than 2600 species. One clade, the "Ginger families", including (Costaceae + Zingiberaceae) (Marantaceae + Cannaceae), has been well-resolved and well-supported in all previous studies. However, well-supported reconstructions among the "Banana families" (Musaceae, Heliconiaceae, Lowiaceae, Strelitziaceae), which most likely diverged about 90 Mya, have been difficult to confirm. Supported with anatomical, morphological, single locus, and genome-wide data, nearly every possible phylogenetic placement has been proposed for these families. In an attempt to resolve this complex evolutionary event, hybridization-based target enrichment was used to obtain sequences from up to 378 putatively orthologous low-copy nuclear genes (all ≥ 960 bp). Individual gene trees recovered multiple topologies among the early divergent lineages, with varying levels of support for these relationships. One topology of the "Banana families" (Musaceae (Heliconiaceae (Lowiaceae + Strelitziaceae))), which has not been suggested until now, was almost consistently recovered in all multilocus analyses of the nuclear dataset (concatenated - ExaML, coalescent - ASTRAL and ASTRID, supertree - MRL, and Bayesian concordance - BUCKy). Nevertheless, the multiple topologies recovered among these lineages suggest that even large amounts of genomic data might not be able to fully resolve relationships at this phylogenetic depth. This lack of well-supported resolution could suggest methodological problems (i.e., violation of model assumptions in both concatenated and coalescent analyses) or more likely reflect an evolutionary history shaped by an explosive, rapid, and nearly simultaneous polychotomous radiation in this group of plants towards the end of the Cretaceous, perhaps driven by vertebrate pollinator selection.


Assuntos
Genômica , Filogenia , Clima Tropical , Zingiberales/classificação , Zingiberales/genética , Teorema de Bayes , Núcleo Celular/genética , Bases de Dados Genéticas , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta/genética
3.
Am J Bot ; 105(8): 1389-1400, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30071130

RESUMO

PREMISE OF THE STUDY: Inclusion of fossils in phylogenetic analyses is necessary in order to construct a comprehensive "tree of death" and elucidate evolutionary history of taxa; however, such incorporation of fossils in phylogenetic reconstruction is dependent on the availability and interpretation of extensive morphological data. Here, the Zingiberales, whose familial relationships have been difficult to resolve with high support, are used as a case study to illustrate the importance of including fossil taxa in systematic studies. METHODS: Eight fossil taxa and 43 extant Zingiberales were coded for 39 morphological seed characters, and these data were concatenated with previously published molecular sequence data for analysis in the program MrBayes. KEY RESULTS: Ensete oregonense is confirmed to be part of Musaceae, and the other seven fossils group with Zingiberaceae. There is strong support for Spirematospermum friedrichii, Spirematospermum sp. 'Goth', S. wetzleri, and Striatornata sanantoniensis in crown Zingiberaceae while "Musa" cardiosperma, Spirematospermum chandlerae, and Tricostatocarpon silvapinedae are best considered stem Zingiberaceae. Inclusion of fossils explains how different topologies from morphological and molecular data sets is due to shared plesiomorphic characters shared by Musaceae, Zingiberaceae, and Costaceae, and most of the fossils. CONCLUSIONS: Inclusion of eight fossil taxa expands the Zingiberales tree and helps explain the difficulty in resolving relationships. Inclusion of fossils was possible in part due to a large morphological data set built using nondestructive microcomputed tomography data. Collaboration between paleo- and neobotanists and technology such as microcomputed tomography will help to build the tree of death and ultimately improve our understanding of the evolutionary history of monocots.


Assuntos
Fósseis/anatomia & histologia , Filogenia , Zingiberales/genética
4.
J Exp Zool B Mol Dev Evol ; 328(1-2): 41-54, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28120453

RESUMO

The evolution of floral morphology in the monocot order Zingiberales shows a trend in which androecial whorl organs are progressively modified into variously conspicuous "petaloid" structures with differing degrees of fertility. Petaloidy of androecial members results from extensive laminarization of an otherwise radially symmetric structure. The genetic basis of the laminarization of androecial members has been addressed through recent candidate gene studies focused on understanding the spatiotemporal expression patterns of genes known to be necessary to floral organ formation. Here, we explore the correlation between gene duplication events and floral and inflorescence morphological diversification across the Zingiberales by inferring ancestral character states and gene copy number using the most widely accepted phylogenetic hypotheses. Our results suggest that the duplication and differential loss of GLOBOSA (GLO) copies is correlated with a change in the degree of the laminarization of androecial members. We also find an association with increased diversification in most families. We hypothesize that retention of paralogs in flower development genes could have led to a developmental shift affecting androecial organs with potential adaptive consequences, thus favoring diversification in some lineages but not others.


Assuntos
Flores/anatomia & histologia , Flores/genética , Zingiberales/anatomia & histologia , Zingiberales/genética , Flores/fisiologia , Zingiberales/classificação , Zingiberales/fisiologia
5.
Sci Rep ; 6: 20255, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26837600

RESUMO

Thaumatin is an intensely sweet-tasting protein that elicits sweet taste at a concentration of 50 nM, a value 100,000 times larger than that of sucrose on a molar basis. Here we attempted to produce a protein with enhanced sweetness by removing negative charges on the interacting side of thaumatin with the taste receptor. We obtained a D21N mutant which, with a threshold value 31 nM is much sweeter than wild type thaumatin and, together with the Y65R mutant of single chain monellin, one of the two sweetest proteins known so far. The complex model between the T1R2-T1R3 sweet receptor and thaumatin, derived from tethered docking in the framework of the wedge model, confirmed that each of the positively charged residues critical for sweetness is close to a receptor residue of opposite charge to yield optimal electrostatic interaction. Furthermore, the distance between D21 and its possible counterpart D433 (located on the T1R2 protomer of the receptor) is safely large to avoid electrostatic repulsion but, at the same time, amenable to a closer approach if D21 is mutated into the corresponding asparagine. These findings clearly confirm the importance of electrostatic potentials in the interaction of thaumatin with the sweet receptor.


Assuntos
Asparagina/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Zingiberales/metabolismo , Sítios de Ligação , Modelos Moleculares , Simulação de Acoplamento Molecular , Mutação , Proteínas de Plantas/metabolismo , Ligação Proteica , Conformação Proteica , Eletricidade Estática , Paladar , Zingiberales/genética
6.
PLoS One ; 11(1): e0147499, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26799570

RESUMO

miRNAs are endogenous small RNA (sRNA) that play critical roles in plant development processes. Canna is an ornamental plant belonging to family Cannaceae. Here, we report for the first time the identification and differential expression of miRNAs in two contrasting flower color cultivars of Canna, Tropical sunrise and Red president. A total of 313 known miRNAs belonging to 78 miRNA families were identified from both the cultivars. Thirty one miRNAs (17 miRNA families) were specific to Tropical sunrise and 43 miRNAs (10 miRNA families) were specific to Red president. Thirty two and 18 putative new miRNAs were identified from Tropical sunrise and Red president, respectively. One hundred and nine miRNAs were differentially expressed in the two cultivars targeting 1343 genes. Among these, 16 miRNAs families targeting 60 genes were involved in flower development related traits and five miRNA families targeting five genes were involved in phenyl propanoid and pigment metabolic processes. We further validated the expression analysis of a few miRNA and their target genes by qRT-PCR. Transcription factors were the major miRNA targets identified. Target validation of a few randomly selected miRNAs by RLM-RACE was performed but was successful with only miR162. These findings will help in understanding flower development processes, particularly the color development in Canna.


Assuntos
Flores/genética , MicroRNAs/genética , Zingiberales/genética , Carotenoides/análise , Cor , Flavonoides/análise , Flores/química , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/genética , MicroRNAs/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Zingiberales/crescimento & desenvolvimento
7.
Ann Bot ; 113(1): 119-33, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24280362

RESUMO

BACKGROUND AND AIMS: Zingiberales comprise a clade of eight tropical monocot families including approx. 2500 species and are hypothesized to have undergone an ancient, rapid radiation during the Cretaceous. Zingiberales display substantial variation in floral morphology, and several members are ecologically and economically important. Deep phylogenetic relationships among primary lineages of Zingiberales have proved difficult to resolve in previous studies, representing a key region of uncertainty in the monocot tree of life. METHODS: Next-generation sequencing was used to construct complete plastid gene sets for nine taxa of Zingiberales, which were added to five previously sequenced sets in an attempt to resolve deep relationships among families in the order. Variation in taxon sampling, process partition inclusion and partition model parameters were examined to assess their effects on topology and support. KEY RESULTS: Codon-based likelihood analysis identified a strongly supported clade of ((Cannaceae, Marantaceae), (Costaceae, Zingiberaceae)), sister to (Musaceae, (Lowiaceae, Strelitziaceae)), collectively sister to Heliconiaceae. However, the deepest divergences in this phylogenetic analysis comprised short branches with weak support. Additionally, manipulation of matrices resulted in differing deep topologies in an unpredictable fashion. Alternative topology testing allowed statistical rejection of some of the topologies. Saturation fails to explain observed topological uncertainty and low support at the base of Zingiberales. Evidence for conflict among the plastid data was based on a support metric that accounts for conflicting resampled topologies. CONCLUSIONS: Many relationships were resolved with robust support, but the paucity of character information supporting the deepest nodes and the existence of conflict suggest that plastid coding regions are insufficient to resolve and support the earliest divergences among families of Zingiberales. Whole plastomes will continue to be highly useful in plant phylogenetics, but the current study adds to a growing body of literature suggesting that they may not provide enough character information for resolving ancient, rapid radiations.


Assuntos
Filogenia , Plastídeos/genética , Zingiberales/genética , Evolução Biológica , Códon , Gengibre/genética , Modelos Genéticos , Dados de Sequência Molecular , Proteínas de Plantas/genética , Zingiberales/classificação
8.
Mol Biol Evol ; 30(11): 2401-22, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23938867

RESUMO

The diversity of floral forms in the plant order Zingiberales has evolved through alterations in floral organ morphology. One striking alteration is the shift from fertile, filamentous stamens to sterile, laminar (petaloid) organs in the stamen whorls, attributed to specific pollination syndromes. Here, we examine the role of the SEPALLATA (SEP) genes, known to be important in regulatory networks underlying floral development and organ identity, in the evolution of development of the diverse floral organs phenotypes in the Zingiberales. Phylogenetic analyses show that the SEP-like genes have undergone several duplication events giving rise to multiple copies. Selection tests on the SEP-like genes indicate that the two copies of SEP3 have mostly evolved under balancing selection, probably due to strong functional restrictions as a result of their critical role in floral organ specification. In contrast, the two LOFSEP copies have undergone differential positive selection, indicating neofunctionalization. Reverse transcriptase-polymerase chain reaction, gene expression from RNA-seq data, and in situ hybridization analyses show that the recovered genes have differential expression patterns across the various whorls and organ types found in the Zingiberales. Our data also suggest that AGL6, sister to the SEP-like genes, may play an important role in stamen morphology in the Zingiberales. Thus, the SEP-like genes are likely to be involved in some of the unique morphogenetic patterns of floral organ development found among this diverse order of tropical monocots. This work contributes to a growing body of knowledge focused on understanding the role of gene duplications and the evolution of entire gene networks in the evolution of flower development.


Assuntos
Evolução Molecular , Flores/crescimento & desenvolvimento , Duplicação Gênica , Genes de Plantas , Proteínas de Plantas/metabolismo , Zingiberales/classificação , Zingiberales/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Fenótipo , Filogenia , Proteínas de Plantas/genética , Seleção Genética , Zingiberales/crescimento & desenvolvimento
9.
Appl Biochem Biotechnol ; 169(1): 228-38, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23179283

RESUMO

Expressed sequence tags (ESTs) databases of 11 Musa complementary DNA libraries were retrieved from National Center of Biotechnology Information and used for mining simple sequence repeats (SSRs). Out of 21,056 unique ESTs, SSR regions were found only in 5,158 ESTs. Among these SSR containing ESTs, the occurrence of trinucleotide repeats are the most abundant followed by mono-, di-, tetra-, hexa-, and pentanucleotides. Moreover, this study showed that the rate of class II SSRs (<20 nucleotides) was higher than the class I SSRs (<20 nucleotides), and proportion of class I and II SSRs as abundant for tri-repeats. As a representative sample, primers were synthesized for 24 ESTs, carrying >12 nucleotides of SSR region, and tested among the various genomic group of Musa accessions. The result showed that 88 % of primers were functional primers, and 43 % are showing polymorphism among the Musa accessions. Transferability studies of Musa EST-SSRs among the genera of the order Zingiberales exhibited 100 and 58 % transferability in Musaceae and Zingiberaceae, respectively. The sequence comparison of SSR regions among the different Musa accessions confirmed that polymorphism is mainly due to the variation in repeat length. High percentage of cross-species, cross-genera, and cross-family transferability also suggested that these Musa EST-SSR markers will be a valuable resource for the comparative mapping by developing COS markers, in evolutionary studies and in improvement of the members of Zingiberaceae and Musaceae.


Assuntos
Etiquetas de Sequências Expressas , Repetições de Microssatélites , Musa/genética , Zingiberales/genética , Sequência de Bases , Primers do DNA/genética , Mineração de Dados , Marcadores Genéticos , Dados de Sequência Molecular , Musa/classificação , Polimorfismo Genético , Zingiberales/classificação
10.
Plant Biol (Stuttg) ; 14(6): 972-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22676855

RESUMO

Somaclonal variation of some 124 specially selected cultivars of Hosta Tratt. (Hostaceae) was investigated. Nuclear DNA contents (2C-value) were measured by flow cytometry of leaves and roots of L1, L2 and L3 layers derived from apical meristems. These values were then converted to inferred ploidies by comparing the measured 2C-values and ploidy with those of the parent plant. During tissue-culture propagation, on occasion diploid (L1-L2-L3 = 2-2-2) hostas give rise to polyploids, such as fully tetraploids (4-4-4), and periclinal chimeras, such as partial tetraploids (4-2-2). Continual propagation can result in partial tetraploids becoming full tetraploids. Nuclear DNA of some diploids increased with incomplete chromosome sets resulting in fully aneuploids, such as hostas with a DNA ploidy of L1-L2-L3 = 2.5-2.5-2.5 and 3.7-3.7-3.7, and even in aneuploid periclinal chimeras, such as L1-L2-L3 = 2.5-2-2 and 3.8-2-2. The polyploidy of L1, irrespective of the ploidy of L2 and L3, is found to mainly determine the thickness of leaves. Also the higher the ploidy of L1, the wider and more intense in color is the leaf margin. The measurements of Hosta cultivars and their lineages of sports show that chromosome losses or gains are an important source of new cultivars. The complexity of chromosomal distribution in lineages of several Hosta cultivars is discussed.


Assuntos
Aneuploidia , Quimera/genética , Variação Genética , Poliploidia , Zingiberales/genética , Núcleo Celular/genética , Quimera/fisiologia , Cromossomos de Plantas/genética , DNA de Plantas/genética , Citometria de Fluxo , Genoma de Planta , Folhas de Planta/genética , Folhas de Planta/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Especificidade da Espécie , Técnicas de Cultura de Tecidos , Zingiberales/fisiologia
11.
Am J Bot ; 98(2): 227-43, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21613112

RESUMO

PREMISE OF THE STUDY: Floral symmetry is a trait of key importance when considering floral diversification because it is thought to play a significant role in plant-pollinator interactions. The CYCLOIDEA/TEOSINTE BRANCHED1 (CYC/TB1)-like genes have been implicated in the development and evolution of floral symmetry in numerous lineages. We thus chose to investigate a possible role for these genes in the evolution of floral symmetry within petaloid monocots, using the order Zingiberales as a model system. In the Zingiberales, evolutionary shifts in symmetry have occurred in all floral whorls, making the order ideal for studying the evolution of this ecologically significant trait. METHODS: We analyzed TB1-like (TBL) genes from taxa spanning the order in a phylogenetic context. Using RNA in situ hybridization, we examined the expression of two TBL genes in Costus spicatus (Costaceae) and Heliconia stricta (Heliconiaceae), taxa with divergent floral symmetry patterns. KEY RESULTS: We identified Zingiberales-specific gene duplications as well as a duplication in the TBL gene lineage that predates the diversification of commelinid monocots. Shifts in TBL gene expression were associated with evolutionary shifts in floral symmetry and stamen abortion. ZinTBL1a expression was found in the posterior (adaxial) staminode of H. stricta and in the abaxial staminodial labellum of C. spicatus. ZinTBL2 expression was strongest in the anterior (abaxial) sepals of H. stricta and in the adaxial fertile stamen of C. spicatus. CONCLUSIONS: This study adds to the growing body of evidence that CYC/TB1-like genes have been repeatedly recruited throughout the course of evolution to generate bilateral floral symmetry (zygomorphy).


Assuntos
Evolução Biológica , Flores/anatomia & histologia , Expressão Gênica , Genes de Plantas , Proteínas de Plantas/metabolismo , Polinização/genética , Zingiberales/metabolismo , Costus/genética , Costus/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Duplicação Gênica , Heliconiaceae/genética , Heliconiaceae/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zingiberales/genética
12.
New Phytol ; 187(2): 521-41, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20456055

RESUMO

SUMMARY: *The MADS box transcription factor family has long been identified as an important contributor to the control of floral development. It is often hypothesized that the evolution of floral development across angiosperms and within specific lineages may occur as a result of duplication, functional diversification, and changes in regulation of MADS box genes. Here we examine the role of Globosa (GLO)-like genes, members of the B-class MADS box gene lineage, in the evolution of floral development within the monocot order Zingiberales. *We assessed changes in perianth and stamen whorl morphology in a phylogenetic framework. We identified GLO homologs (ZinGLO1-4) from 50 Zingiberales species and investigated the evolution of this gene lineage. Expression of two GLO homologs was assessed in Costus spicatus and Musa basjoo. *Based on the phylogenetic data and expression results, we propose several family-specific losses and gains of GLO homologs that appear to be associated with key morphological changes. The GLO-like gene lineage has diversified concomitant with the evolution of the dimorphic perianth and the staminodial labellum. *Duplications and expression divergence within the GLO-like gene lineage may have played a role in floral diversification in the Zingiberales.


Assuntos
Evolução Molecular , Flores/anatomia & histologia , Duplicação Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Proteínas de Homeodomínio/genética , Proteínas de Plantas/genética , Zingiberales/genética , Teorema de Bayes , Commelina/genética , Flores/citologia , Flores/genética , Dosagem de Genes/genética , Modelos Genéticos , Nucleotídeos/genética , Filogenia , Homologia de Sequência do Ácido Nucleico , Zingiberales/anatomia & histologia
13.
Appl Biochem Biotechnol ; 162(7): 1938-51, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20419479

RESUMO

The objective of this study was to investigate a new protein with α-glucosidase inhibitory activity from the rhizomes of Zingiber ottensii. With a simple salting-out technique followed by single-step anion-exchange purification, the protein was successfully purified from the rhizomes. This protein was found to have three likely sub-unit types, 32.5, 15.2, and 13.8 kDa, as revealed by native and reducing SDS-PAGE analysis. Determination of the kinetics of the inhibition of α-glucosidase from Saccharomyces cerevisiae by standard enzymatic methods indicated the maximum percent inhibition; IC(50) and K ( i ) of this protein were 77.5%, 30.15 µg/ml, and 140 µmol, while the K ( m ) and V ( max ) were 2.35 µmol and 0.11 mM/min, respectively. The inhibitory action was pH-independent within the pH range 2-10, but was potentially affected by buffer salts, and was relatively temperature-stable between 4-35 °C, with a maximum activity at 65 °C. The amino acid sequence of an internal fragment of this purified Z. ottensii rhizomal protein had a similarity to the sequence from the plant cysteine proteinase family. Although this α-glucosidase inhibitory protein was purified from Z. ottensii rhizomes and preliminarily characterized, further studies are needed prior to firm applications being envisaged.


Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Proteínas de Plantas/farmacologia , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Zingiberales/química , Sequência de Aminoácidos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Cinética , Dados de Sequência Molecular , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Rizoma/química , Rizoma/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Alinhamento de Sequência , Zingiberales/genética , alfa-Glucosidases/química
14.
Ann Bot ; 92(4): 571-80, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14507742

RESUMO

This paper presents the first record of silica deposits in tissues of Haemodoraceae and adds new records of tapetal raphides in this family. Within the order Commelinales, silica is present in leaves of three families (Hanguanacaeae, Haemodoraceae and Commelinaceae), but entirely absent from the other two (Pontederiaceae and Philydraceae). Presence or absence of characteristic cell inclusions may have systematic potential in commelinid monocotyledons, although the existing topology indicates de novo gains and losses in individual families. Silica sand was observed in leaves of five out of nine genera examined of Haemodoraceae, predominantly in vascular bundle sheath cells and epidermal cells. Within Haemodoraceae, silica is limited to subfamily Conostylidoideae. The occurrence of silica in Phlebocarya supports an earlier transfer of this genus from Haemodoroideae to Conostylidoideae. The presence of raphides (calcium oxalate crystals) in the anther tapetum represents a rare character, only reported in a few monocot families of the order Commelinales, and possibly representing a mechanism for regulation of cytoplasmic free calcium levels. Tapetal raphides were observed here in Anigozanthus and Conostylis (both Haemodoraceae), and Tradescantia (Commelinaceae), thus supplementing two earlier records in Haemodoraceae, Philydraceae and Commelinaceae.


Assuntos
Oxalato de Cálcio/metabolismo , Flores/metabolismo , Magnoliopsida/metabolismo , Folhas de Planta/metabolismo , Dióxido de Silício/metabolismo , Oxalato de Cálcio/química , Commelinaceae/genética , Commelinaceae/metabolismo , Cristalização , Flores/ultraestrutura , Magnoliopsida/genética , Microscopia Eletrônica , Filogenia , Folhas de Planta/ultraestrutura , Pontederiaceae/genética , Pontederiaceae/metabolismo , Zingiberales/genética
15.
Mol Phylogenet Evol ; 21(3): 333-45, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11741377

RESUMO

The phylogenetic relationships of Costaceae, a tropical monocotyledonous family sister to the gingers (Zingiberaceae), were investigated with a combination of two chloroplast loci (the trnL-F locus, including the trnL intron, the 3'trnL exon, and the trnL-F intergenic spacer, and the trnK locus, including the trnK intron and the matK coding region) and one nuclear locus (ITS1-5.8s-ITS2). The resulting parsimony analysis of selected taxa that demonstrate the range of floral morphological variation in the family shows that the Cadalvena-type [corrected] floral morphology is ancestral to the group and that both Tapeinochilos species and a Monocostus + Dimerocostus clade represent recent divergences. The genus Costus is broadly paraphyletic but Costus subgenus Eucostus K. Schum. represents a large monophyletic radiation that is poorly resolved. Within this clade, secondary analyses suggest that pollination syndrome, traditionally used for taxonomic and classification purposes within the genus Costus, is a relatively plastic trait of limited phylogenetic utility. This represents the first detailed investigation into intrageneric and interspecific evolutionary relationships within the family Costaceae and presents some novel evolutionary trends with respect to floral morphology and biogeography.


Assuntos
Filogenia , Zingiberales/genética , Cloroplastos/genética , Evolução Molecular , Éxons , Zingiberales/classificação
16.
Sheng Wu Gong Cheng Xue Bao ; 17(3): 293-6, 2001 May.
Artigo em Chinês | MEDLINE | ID: mdl-11517603

RESUMO

Based on our cDNA sequence of ACC synthase gene expressed specifically in banana fruit, we cloned the 5'-flanking proximal region of 1197 bp and distal region of 1556 bp via walking on unknown region of genomic DNA by an improved adaptor ligation PCR, and created a 2591 bp fragment containing a promoter region of 2505 bp and a transcriptional region of 86 bp. The entire 2.5 kb promoter and 5 different 5' deletion variants were fused to the GUS (beta-glucuronidase) cDNA sequence and introduced into leaf, root and fruit cells of banana plant via particle bombardment separately. The results of transient gene expression assay indicated that the obtained promoter region could direct fruit-specific gene expression. The regulatory region for fruit-specificity was possibly located in the region from -1111 to +1 and a positive regulatory region may locate between nucleotide -1111 to -608.


Assuntos
Liases/genética , Regiões Promotoras Genéticas , Zingiberales/genética , Sequência de Bases , Clonagem Molecular , Liases/fisiologia , Dados de Sequência Molecular
18.
Syst Biol ; 50(6): 926-44, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12116641

RESUMO

The Zingiberales are a tropical group of monocotyledons that includes bananas, gingers, and their relatives. The phylogenetic relationships among the eight families currently recognized are investigated here by using parsimony and maximum likelihood analyses of four character sets: morphological features (1), and sequence data of the (2) chloroplast rbcL gene, (3) chloroplast atpB gene, and (4) nuclear 18S rDNA gene. Outgroups for the analyses include the closely related Commelinaceae + Philydraceae + Haemodoraceae + Pontederiaceae + Hanguanaceae as well as seven more distantly related monocots and paleoherbs. Only slightly different estimates of evolutionary relationships result from the analysis of each character set. The morphological data yield a single fully resolved most-parsimonious tree. None of the molecular datasets alone completely resolves interfamilial relationships. The analyses of the combined molecular dataset provide more resolution than do those of individual genes, and the addition of the morphological data provides a well-supported estimate of phylogenetic relationships: (Musaceae ((Strelitziaceae, Lowiaceae) (Heliconiaceae ((Zingiberaceae, Costaceae) (Cannaceae, Marantaceae))))). Evidence from branch lengths in the parsimony analyses and from the fossil record suggests that the Zingiberales originated in the Early Cretaceous and underwent a rapid radiation in the mid-Cretaceous, by which time most extant family lineages had diverged.


Assuntos
Evolução Molecular , Zingiberales/classificação , Zingiberales/genética , DNA de Plantas/genética , Bases de Dados Factuais , Bases de Dados Genéticas , Fósseis , Genes de Plantas , Modelos Genéticos , Filogenia , RNA Ribossômico 18S/genética , Ribulose-Bifosfato Carboxilase/genética , Zingiberales/anatomia & histologia
20.
Genome ; 43(5): 763-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11081965

RESUMO

Plantains and bananas (Musa spp. sect. eumusa) originated from intra- and interspecific hybridization between two wild diploid species, M. acuminata Colla. and M. balbisiana Colla., which contributed the A and B genomes, respectively. Polyploidy and hybridization have given rise to a number of diploid, triploid, and tetraploid clones with different permutations of the A and B genomes. Thus, dessert and highland bananas are classified mainly as AAA, plantains are AAB, and cooking bananas are ABB. Classification of Musa into genomic groups has been based on morphological characteristics. This study aimed to identify RAPD (random amplified polymorphic DNA) markers for the A and B genomes. Eighty 10-mer Operon primers were used to amplify DNA from M. acuminata subsp. burmannicoides clone 'Calcutta 4' (AA genomes) and M. balbisiana clone 'Honduras' (BB genomes). Three primers (A17, A18, and D10) that produced unique genome-specific fragments in the two species were identified. These primers were tested in a sample of 40 genotypes representing various genome combinations. The RAPD markers were able to elucidate the genome composition of all the genotypes. The results showed that RAPD analysis can provide a quick and reliable system for genome identification in Musa that could facilitate genome characterization and manipulations in breeding lines.


Assuntos
Marcadores Genéticos , Genoma de Planta , Técnica de Amplificação ao Acaso de DNA Polimórfico , Zingiberales/genética , Animais , Quimera , Primers do DNA , Poliploidia
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