RESUMO
Berries and red fruits are important dietary sources of polyphenols [1]. In vitro and animal studies have demonstrated the bioavailability and the anti-proliferative and anticarcinogenic properties of these fruits or of their phenolic components [2, 3]. Consumption of berries may contribute to the reduction of colon cancer by mechanisms not yet understood. Gene expression analysis using microarrays allows for a more comprehensive study of the possible molecular mechanisms by which food or food components may prevent certain cancers of the gastrointestinal tract [4]. The aim of this research is to investigate the anti-proliferative effects of a polyphenol-rich berry juice on a human model of colon cancer cells and its association to transcriptional changes in relation to colon cancer.
RESUMO
Considering the design and development of biomaterials used in tissue engineering, not only is it important that they are biocompatible but also that they induce the desired cellular response for tissue regeneration. Chitosan, a biocompatible and bioresorbable polymer of N-acetylglucosamine and glucosamine is used in our work combined with recombinant human BMP-2 (rhBMP-2), a potentially useful activation factor for bone repair. In this way, we try to combine the biological and filmogenic properties of this biopolymer with the osseoinductive ability of the rhBMP-2. Results showed that the chitosan films employed, without and with rhBMP-2 activation, are able to support cellular growth and proliferation on them and that only the rhBMP-2 activated ones are able to differentiate from a myoblastic mouse cell line (C2C12) toward osteoblastic phenotype. Osseoinduction properties of rhBMP-2 activated films persist for a long storage time. The in vivo experiments performed confirm the expectative created by the in vitro results obtained and are an indication that rhBMP-2 activated chitosan films could be a very attractive biomaterial for the enhancement of osseointegration of surgical prostheses and implants and for the purpose of tissue engineering bone regeneration.
Assuntos
Materiais Biocompatíveis/química , Proteínas Morfogenéticas Ósseas/farmacologia , Quitosana/química , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Proteína Morfogenética Óssea 2 , Técnicas de Cultura de Células/instrumentação , Quitina/química , Crustáceos , Fluoresceínas/química , Humanos , Masculino , Camundongos , Peso Molecular , Osseointegração , CoelhosRESUMO
As a part of the EUROFAN program, 24 open reading frames from Saccharomyces cerevisiae (YKR010c to YKR013w, YKR015c to YKR025w, YKR081c to YKR083c, YKR087c to YKR091w and YKR096w) were disrupted in two genetic backgrounds, FY1679 and W303. Systematic deletions and phenotypic analysis were performed following a hierarchical strategy, the so-called 'mass murder'. Of the 24 genes thus deleted, four are essential, whereas the deletion of 17 did not reveal any significant difference between the parental and mutant strains. Deletions of the remaining three show some growth phenotype; ykr024c mutants grow slowly under any conditions, ykr019c mutants grow slower in a rich medium and ykr082w mutants are temperature sensitive, being unable to germinate at 30 degrees C and above.
Assuntos
Cromossomos Fúngicos , Saccharomyces cerevisiae/genética , Deleção de Sequência , Sequência de Bases , Primers do DNA , Haploidia , Temperatura Alta , Mutação , Fases de Leitura Aberta , Fenótipo , Saccharomyces cerevisiae/crescimento & desenvolvimentoRESUMO
The complete DNA sequence of the yeast Saccharomyces cerevisiae chromosome IV has been determined. Apart from chromosome XII, which contains the 1-2 Mb rDNA cluster, chromosome IV is the longest S. cerevisiae chromosome. It was split into three parts, which were sequenced by a consortium from the European Community, the Sanger Centre, and groups from St Louis and Stanford in the United States. The sequence of 1,531,974 base pairs contains 796 predicted or known genes, 318 (39.9%) of which have been previously identified. Of the 478 new genes, 225 (28.3%) are homologous to previously identified genes and 253 (32%) have unknown functions or correspond to spurious open reading frames (ORFs). On average there is one gene approximately every two kilobases. Superimposed on alternating regional variations in G+C composition, there is a large central domain with a lower G+C content that contains all the yeast transposon (Ty) elements and most of the tRNA genes. Chromosome IV shares with chromosomes II, V, XII, XIII and XV some long clustered duplications which partly explain its origin.
Assuntos
Cromossomos Fúngicos , Saccharomyces cerevisiae/genética , Sequência de Bases , DNA Fúngico , Dados de Sequência MolecularRESUMO
In 1992 we started assembling an ordered library of cosmid clones from chromosome XIV of the yeast Saccharomyces cerevisiae. At that time, only 49 genes were known to be located on this chromosome and we estimated that 80% to 90% of its genes were yet to be discovered. In 1993, a team of 20 European laboratories began the systematic sequence analysis of chromosome XIV. The completed and intensively checked final sequence of 784,328 base pairs was released in April, 1996. Substantial parts had been published before or had previously been made available on request. The sequence contained 419 known or presumptive protein-coding genes, including two pseudogenes and three retrotransposons, 14 tRNA genes, and three small nuclear RNA genes. For 116 (30%) protein-coding sequences, one or more structural homologues were identified elsewhere in the yeast genome. Half of them belong to duplicated groups of 6-14 loosely linked genes, in most cases with conserved gene order and orientation (relaxed interchromosomal synteny). We have considered the possible evolutionary origins of this unexpected feature of yeast genome organization.
Assuntos
Cromossomos Fúngicos , Evolução Molecular , Saccharomyces cerevisiae/genética , Sequência de Bases , Dados de Sequência Molecular , Família Multigênica , Fases de Leitura Aberta , Mapeamento por RestriçãoRESUMO
As part of the European BIOTECH programme, the nucleotide sequence of a 16691 bp fragment from the left arm of chromosome IV of Saccharomyces cerevisiae has been deduced. Analysis of the sequence reveals the presence of 13 open reading frames (ORFs) larger than 100 codons. five of these were previously identified as genes DUN1, PMT1, PMT5, SRP14 and DPR1. One putative protein, D2371p, contains an ATP-GTP binding site, and shares homology to the ArsA component of an Escherichia coli arsenical pump. No significant homology to any known protein has been found for the other ORFs. D2378p contains a zinc finger domain.
Assuntos
Proteínas de Ciclo Celular , Proteínas Fúngicas/genética , Manosiltransferases/genética , Fases de Leitura Aberta/genética , Proteínas Quinases/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Partícula de Reconhecimento de Sinal/genética , Transferases/genética , Sequência de Aminoácidos , Clonagem Molecular , Processamento Eletrônico de Dados , Dados de Sequência Molecular , Plasmídeos , Proteínas Serina-Treonina Quinases , Mapeamento por Restrição , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
As part of the EU yeast genome program, a fragment of 14,262 bp from the left arm of Saccharomyces cerevisiae chromosome XIV has been sequenced. This fragment corresponds to cosmid 14-14b and is located roughly 130 kb from the centromere. It contains four new open reading frames which encode potential proteins of more than 99 amino acids, as well as the ypt53, tRNALeu and gsr moffenes. The putative protein N2212 is similar to the ribosomal protein S7 from humans. N2215 contains several predicted transmembrane elements. N2231 contains regions which are rich in acidic, as well as basic, residues which could from alpha-helical structures. Similar regions are found in a variety of proteins including glutamic acid rich protein, trichohyalin, caldesmon, Tb-29 and several cytoskeleton-interacting proteins.
Assuntos
Proteínas Fúngicas/genética , GTP Fosfo-Hidrolases/genética , Proteínas de Ligação ao GTP/genética , RNA de Transferência de Leucina/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas rab de Ligação ao GTP , Sequência de Aminoácidos , Sequência de Bases , Humanos , Proteínas de Membrana/genética , Dados de Sequência Molecular , Fases de Leitura , Recombinação Genética , Proteínas Ribossômicas/genética , Homologia de Sequência de AminoácidosRESUMO
We report the sequence of an 18,002 bp DNA fragment from the right arm of Saccharomyces cerevisiae chromosome XI. This segment contains nine complete open reading frames (ORFs), YKR401 to YKR409, and part of another ORF, YKR400, covering altogether 87.2% of the entire sequence. One of them, YKR400, encodes an NAD-dependent 5,10-methylene-tetrahydrofolate dehydrogenase. YKR404, YKR405 and YKR406 correspond to the previously characterized HBS1, MRP-L20 and PRP16 genes, coding for a translation elongation factor, a mitochondrial ribosomal protein and an ATP-binding protein, respectively. The putative product of YKR407 contains the zinc-binding region signature of neutral zinc metallopeptidases. The five other ORFs do not show significant homology to any known protein.