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1.
Mol Phylogenet Evol ; 171: 107461, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35351631

RESUMEN

Miconia is among the largest plant genera in the Neotropics and a taxonomically complex lineage. Indeed, molecular phylogenetic data shows that none of its traditionally accepted sections are monophyletic, preventing taxonomic advances within the genus. Miconia is the largest plant genus in the Brazilian Atlantic Forest, including three main lineages, the Leandra s.s. clade (ca. 215 spp.), the Miconia sect. Chaenanthera (24 spp.), and the Miconia discolor clade (estimated 77 spp.). Out of these lineages, the Miconia discolor clade is the only currently lacking phylogenetic data, complicating its taxonomy. In this study, we reconstruct the phylogeny of the Miconia discolor clade, using three plastid (atpF-H, psbK-I, and psaI-accD) and two nuclear (ETS and ITS) markers. We sampled 60 out of the 77 species of the group, representing 78% of its diversity. Taxa were selected considering their distribution, morphology, and previous phylogenetic knowledge. We used the newly reconstructed phylogeny to better understand phylogenetic relationships among Atlantic Forest species and morphologically similar taxa, and to propose a new infrageneric classification for the Miconia discolor clade: the Miconia supersection Discolores. We further studied the evolution of seven morphological characters using a Maximum Likelihood approach, and estimated the ancestral range distribution of various lineages in order to understand the biogeographic history of this clade. We found that dichasial inflorescences represent the ancestral condition within Miconia, subsequently giving rise to scorpioid and glomerulate inflorescences in the studied group. We describe Miconia supersect. Discolores, originated in the Amazon region, which is recognized by a dense layer of branched tricomes covering young branches and non-dichasial inflorescences, including three main lineages: (i) Miconia sect. Albicantes, characterized by persistent bracts and arachnoid indument on the abaxial surface of leaves, mainly distributed in the Amazon basin; (ii) Miconia sect. Discolores, characterized by caducous calyx lobes and glomerulate inflorescences, centered in the Atlantic Forest; and (iii) Miconia sect. Multispicatae, characterized by leaves not completely covered with indument, and capitate stigma, mainly distributed in the Atlantic Forest. All three sections and the supersection originated in the Neogene, between the Late Miocene and the Early Pliocene.


Asunto(s)
Melastomataceae , Teorema de Bayes , Bosques , Funciones de Verosimilitud , Melastomataceae/anatomía & histología , Filogenia
2.
Am J Bot ; 108(7): 1252-1269, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34287829

RESUMEN

PREMISE: The carrot family (Apiaceae) comprises 466 genera, which include many well-known crops (e.g., aniseed, caraway, carrots, celery, coriander, cumin, dill, fennel, parsley, and parsnips). Higher-level phylogenetic relationships among subfamilies, tribes, and other major clades of Apiaceae are not fully resolved. This study aims to address this important knowledge gap. METHODS: Target sequence capture with the universal Angiosperms353 probe set was used to examine phylogenetic relationships in 234 genera of Apiaceae, representing all four currently recognized subfamilies (Apioideae, Azorelloideae, Mackinlayoideae, and Saniculoideae). Recovered nuclear genes were analyzed using both multispecies coalescent and concatenation approaches. RESULTS: We recovered hundreds of nuclear genes even from old and poor-quality herbarium specimens. Of particular note, we placed with strong support three incertae sedis genera (Platysace, Klotzchia, and Hermas); all three occupy isolated positions, with Platysace resolved as sister to all remaining Apiaceae. We placed nine genera (Apodicarpum, Bonannia, Grafia, Haplosciadium, Microsciadium, Physotrichia, Ptychotis, Tricholaser, Xatardia) that have never previously been included in any molecular phylogenetic study. CONCLUSIONS: We provide support for the maintenance of the four existing subfamilies of Apiaceae, while recognizing that Hermas, Klotzschia, and the Platysace clade may each need to be accommodated in additional subfamilies (pending improved sampling). The placement of the currently apioid genus Phlyctidocarpa can be accommodated by the expansion of subfamily Saniculoideae, although adequate morphological synapomorphies for this grouping are yet to be defined. This is the first phylogenetic study of the Apiaceae using high-throughput sequencing methods and represents an unprecedented evolutionary framework for the group.


Asunto(s)
Apiaceae , Daucus carota , Apiaceae/genética , Evolución Biológica , Núcleo Celular/genética , Daucus carota/genética , Filogenia
3.
Neuro Endocrinol Lett ; 32(3): 253-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21712771

RESUMEN

OBJECTIVE: Vesicular monoamine transporter 1 (VMAT-1) mRNA and protein were examined (1) to determine whether adult mouse brain expresses full-length VMAT-1 mRNA that can be translated to functional transporter protein and (2) to compare immunoreactive VMAT-1 proteins in brain and adrenal. METHODS: VMAT-1 mRNA was detected in mouse brain with RT-PCR. The cDNA was sequenced, cloned into an expression vector, transfected into COS-1 cells, and cell protein was assayed for VMAT-1 activity. Immunoreactive proteins were examined on western blots probed with four different antibodies to VMAT-1. RESULTS: Sequencing confirmed identity of the entire coding sequences of VMAT-1 cDNA from mouse medulla oblongata/pons and adrenal to a Gen-Bank reference sequence. Transfection of the brain cDNA into COS-1 cells resulted in transporter activity that was blocked by the VMAT inhibitor reserpine and a proton ionophore, but not by tetrabenazine, which has a high affinity for VMAT-2. Antibodies to either the C- or N- terminus of VMAT-1 detected two proteins (73 and 55 kD) in transfected COS-1 cells. The C-terminal antibodies detected both proteins in extracts of mouse medulla/pons, cortex, hypothalamus, and cerebellum but only the 73 kD protein and higher molecular weight immunoreactive proteins in mouse adrenal and rat PC12 cells, which are positive controls for rodent VMAT-1. CONCLUSIONS: These findings demonstrate that a functional VMAT-1 mRNA coding sequence is expressed in mouse brain and suggest processing of VMAT-1 protein differs in mouse adrenal and brain.


Asunto(s)
Química Encefálica/genética , Proteínas del Tejido Nervioso/biosíntesis , ARN Mensajero/biosíntesis , Proteínas de Transporte Vesicular de Monoaminas/biosíntesis , Proteínas de Transporte Vesicular de Monoaminas/genética , Glándulas Suprarrenales/metabolismo , Animales , Western Blotting , Química Encefálica/inmunología , Células COS , Línea Celular , Membrana Celular/metabolismo , Chlorocebus aethiops , Clonación Molecular , ADN Complementario/genética , Inmunohistoquímica , Ratones , Ratones Endogámicos CBA , Ratones Endogámicos ICR , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Células PC12 , ARN Mensajero/genética , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
4.
Mol Phylogenet Evol ; 53(1): 134-51, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19549570

RESUMEN

As circumscribed by Drude, the umbellifer subfamily Hydrocotyloideae posed a major hindrance to resolving the phylogeny of order Apiales. Previous studies have suggested its polyphyly, but have not had sufficient sampling to address the issue fully. To put an end to the out-dated concept of Hydrocotyloideae, we investigated the placement of 40 of the 42 genera once placed in the subfamily, using extensive taxon sampling across the entire order. Molecular phylogenies were constructed using plastid sequences of the rpl16 intron and the trnD-trnT regions and revealed at least six hydrocotyloid lineages dispersed across both families Apiaceae and Araliaceae. The most speciose of these clades corresponds to the recently erected subfamily Azorelloideae. Another lineage includes genera grouped in Mackinlayoideae, where relationships are well resolved. Platysace appears paraphyletic with respect to Homalosciadium, and their placement is well supported as a basal lineage in Apiaceae. The type genus, Hydrocotyle, belongs to a supported clade in Araliaceae. The placements of Hermas as sister to a clade consisting of Apiaceae subfamilies Apioideae and Saniculoideae, and of Choritaenia as sister to Lichtensteinia in a clade with affinities to both Apioideae and Saniculoideae, calls into question the circumscriptions of the two subfamilies. Finally, plastid data suggest that many former hydrocotyloid genera are non-monophyletic (e.g., Azorella, Schizeilema, and Eremocharis) and are in dire need of additional phylogenetic and taxonomic studies.


Asunto(s)
Apiaceae/genética , Evolución Molecular , Filogenia , Apiaceae/clasificación , ADN de Plantas/genética , Intrones , Plastidios/genética , Alineación de Secuencia , Análisis de Secuencia de ADN
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