Consulta: creatorFacets:"Vanzela,André Luís Laforga"
Registros recuperados: 5
Data/hora: 10/06/2024 07:32:37

Distribution of a Ty3/gypsy-like retroelement on the A and B-chromosomes of Cestrum strigilatum Ruiz &amp;amp; Pav. and Cestrum intermedium Sendtn. (Solanaceae)
Provedor de dados: Genetics and Molecular Biology
Autores: Fregonezi,Jéferson Nunes; Vilas-Boas,Laurival A.; Fungaro,Maria Helena Pelegrinelli; Gaeta,Marcos Letaif; Vanzela,André Luís Laforga.
Retroelements are a diversified fraction of eukaryotic genomes, with the Ty1/copia and Ty3/gypsy groups being very common in a large number of plant genomes. We isolated an internal segment of the Ty3/gypsy retroelement of Cestrum strigilatum (Solanaceae) using PCR amplification with degenerate primers for a conserved region of reverse transcriptase. The isolated segment (pCs12) was sequenced and showed similarity with Ty3/gypsy retroelements of monocotyledons and dicotyledons. This segment was used as probe in chromosomes of C. strigilatum and Cestrum intermedium. Diffuse hybridization signals were observed along the chromosomes and more accentuated terminal signals in some chromosome pairs, always associated with nucleolus organizer regions (NORs). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cestrum strigilatum; Cestrum intermedium; Karyotype organization; Retroelements; Solanaceae; Ty3-gypsy.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000400017

Karyotype differentiation of four Cestrum species (Solanaceae) based on the physical mapping of repetitive DNA
Provedor de dados: Genetics and Molecular Biology
Autores: Fregonezi,Jéferson Nunes; Fernandes,Thiago; Torezan,José Marcelo Domingues; Vieira,Ana Odete S.; Vanzela,André Luís Laforga.
We studied the karyotypes of four Brazilian Cestrum species (C. amictum, C. intermedium, C. sendtnerianum and C. strigilatum) using conventional Feulgen staining, C-Giemsa and C-CMA3/DAPI banding, induction of cold-sensitive regions (CSRs) and fluorescent in situ hybridization (FISH) with rDNA probes. We found that the karyotypes of all four species was 2n = 2x = 16, with, except for the eighth acrocentric pair, a predominance of meta- and submetacentric chromosomes and various heterochromatin classes. Heterochromatic types previously unreported in Cestrum as neutral C-CMA3(0)/DAPI0 bands, CMA3+ bands not associated with NORs, and C-Giemsa/CSR/DAPI- bands were found. The heterochromatic blocks varied in size, number, position and composition. The 45S rDNA...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cestrum; Chromosome banding; CSRs; Karyotype evolution; RDNA probes.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000100019

Karyotype differentiation of four Cestrum species (Solanaceae) revealed by fluorescent chromosome banding and FISH
Provedor de dados: Genetics and Molecular Biology
Autores: Fernandes,Thiago; Rego,Letícia do Nascimento Andrade de Almeida; Nardy,Mariana; Yuyama,Priscila Mary; Vanzela,André Luís Laforga.
The karyotypes of four South American species of Cestrum (C. capsulare, C. corymbosum, C. laevigatum and C. megalophylum) were studied using conventional staining, C-CMA/DAPI chromosome banding and FISH with 45S and 5S rDNA probes. The karyotypes showed a chromosome number of 2n = 2x = 16, with metacentric chromosomes, except for the eighth submeta- to acrocentric pair. Several types of heterochromatin were detected, which varied in size, number, distribution and base composition. The C-CMA+ bands and 45S rDNA were located predominantly in terminal regions. The C-CMA+/DAPI+ bands appeared in interstitial and terminal regions, and the C-DAPI+ bands were found in all chromosome regions. The 5S rDNA sites were observed on the long arm of pair 8 in all species...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cestrum; Chromosome banding; FISH; Heterochromatin; Physical maps; 45S and 5S rDNA.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200019

Hypomethylation of cytosine residues in cold-sensitive regions of Cestrum strigilatum (Solanaceae)
Provedor de dados: Genetics and Molecular Biology
Autores: Guarido,Paula Carolina Paes; Paula,Adriano Alves de; Silva,Carlos Roberto Maximiano da; Rodriguez,Carmen; Vanzela,André Luís Laforga.
Heterochromatin comprises a fraction of the genome usually with highly repeated DNA sequences and lacks of functional genes. This region can be revealed by using Giemsa C-banding, fluorochrome staining and cytomolecular tools. Some plant species are of particular interest through having a special type of heterochromatin denominated the cold-sensitive region (CSR). Independent of other chromosomal regions, when biological materials are subjected to low temperatures (about 0 °C), CSRs appear slightly stained and decondensed. In this study, we used Cestrum strigilatum (Solanaceae) to understand some aspects of CSR condensation associated with cytosine methylation levels, and to compare the behavior of different heterochromatin types of this species, when...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anti-5-methylcytosine; Cestrum; Chromosomes; CMA/DAPI banding; Heterochromatin; Immunolabeling.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000300012

Genetic variability of pre and post-fragmentation cohorts of Aspidosperma polyneuron Muell. Arg. (Apocynaceae)
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Torezan,José Marcelo Domingues; Souza,Rogério Fernandes de; Ruas,Paulo Maurício; Ruas,Claudete de Fátima; Camargo,Elvis Hassmann; Vanzela,André Luís Laforga.
RAPD was used to access the genetic variability in Aspisdosperma polyneuron, a long-lived, late-reproducing tropical tree, and highly important for the Atlantic Forest. RAPD profiles from adults (pre-fragmentation, &gt;300 years old) and seedlings (post-fragmentation, &lt;&lt;50 years old) were analyzed. Results showed a decrease of genetic polymorphism of post-fragmentation cohorts in small fragments and higher genetic diversity within population. The genetic diversity distribution suggested the establishment of fragments as protected reserves, and the transference of seedlings among fragments for conservation of A. polyneuron.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspidosperma; DNA markers; Forest fragmentation; Genetic variability; Peroba-rosa; RAPD.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000200002