RESUMO
To be able to elucidate the function of cyclin D1 in the control of cell cycle progression and its role as an oncogene in tumorigenesis, it is of paramount importance to understand the mechanisms involved in the regulation of its expression. In the present study, we have cloned the human cyclin D1 gene and analysed the structure and function of 3kb of its 5'-flanking region. Several regulatory regions involved in both basal level and serum-induced expression were identified, two of which turned out to be of particular interest. One of these regions is involved in serum induction and is located 848-944 bp upstream of the initiation site. In agreement with this result, in vivo footprinting revealed a novel, strongly inducible protein binding site around positions -928 to -921. A second constitutively occupied binding site was mapped to a potential CRE at position -52. Cotransfection experiments showed that the cyclin D1 promoter is inducible by c-Jun, and that this induction is mediated predominantly through the protected putative CRE at -52.
Assuntos
Ciclinas/genética , Regulação da Expressão Gênica , Proteínas Oncogênicas/genética , Regiões Promotoras Genéticas , Sequência de Bases , Sítios de Ligação , Ciclina D1 , Desoxirribonucleases , Humanos , Dados de Sequência Molecular , Ligação Proteica , Sequências Reguladoras de Ácido Nucleico , Relação Estrutura-AtividadeRESUMO
Dandruff particles contain a considerable portion of nucleated cells within the aggregates of nuclei-free corneocytes. The nuclei could be partially degraded due to epidermal differentiation processes. To test the suitability of DNA from dandruff for forensic application, a study of 35 subjects and two crime cases has been carried out using different STR polymorphisms. In 90% of the samples DNA genotyping could be easily performed indicating that DNA from dandruff is at least suitable for STR analysis. DNA quantity per dandruff particle varies extremely within a range from 0.8 to 16.6 ng DNA for the tested subjects. Genotyping was also possible for a single dandruff particle if DNA extraction volume had been reduced. In mixed samples from dandruff coextracted with bloodstains or semen stains dandruff genotype was detectable. in some cases. These results demonstrate the relevance of dandruff in forensic casework either as an additional sample or as a source of inadvertent contamination.
Assuntos
Impressões Digitais de DNA/métodos , DNA/análise , Sequências Repetitivas de Ácido Nucleico , Dermatoses do Couro Cabeludo/genética , Adulto , Criança , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Dermatoses do Couro Cabeludo/patologia , Sensibilidade e Especificidade , Análise de Sequência de DNARESUMO
Rapidly growing cell suspensions of soybean were analyzed for the presence of cytoplasmic high-affinity binding sites for auxin. Cytosol preparations were studied in lag, log and early stationary phase of the growth cycle. Two binding sites were detected, which show some similarities with binding sites previously reported from etiolated pea epicotyls. While the number of both sites declined in the cytoplasm during the growth cycle, the number of one of the two sites increased at the onset of rapid cell divisions. In parallel, both sites exhibited an increase in binding affinity during the growth cycle. The data will be discussed in relation to other reports on soluble auxin binding as well as to possible physiological functions.