Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do SciELO, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

nfluence of the polymorphisms of the α-major regulatory element HS-40 on in vitro gene expression

Texto completo
Autor(es):
D.M. Ribeiro ; T.R. Zaccariotto ; M.N.N. Santos ; F.F. Costa ; M.F. Sonati
Número total de Autores: 5
Tipo de documento: Artigo Científico
Fonte: Brazilian Journal of Medical and Biological Research; v. 42, n. 9, p. 783-786, Set. 2009.
Assunto(s):Polimorfismo genético
Resumo

The α-MRE is the major regulatory element responsible for the expression of human α-like globin genes. It is genetically polymorphic, and six different haplotypes, named A to F, have been identified in some population groups from Europe, Africa and Asia and in native Indians from two Brazilian Indian tribes. Most of the mutations that constitute the α-MRE haplotypes are located in flanking sequences of binding sites for nuclear factors. To our knowledge, there are no experimental studies evaluating whether such variability may influence the α-MRE enhancer activity. We analyzed and compared the expression of luciferase of nine constructs containing different α-MRE elements as enhancers. Genomic DNA samples from controls with A (wild-type α-MRE) and B haplotypes were used to generate C-F haplotypes by site-directed mutagenesis. In addition, three other elements containing only the G→A polymorphism at positions +130, +199, and +209, separately, were also tested. The different α-MRE elements were amplified and cloned into a plasmid containing the luciferase reporter gene and the SV40 promoter and used to transiently transfect K562 cells. A noticeable reduction in luciferase expression was observed with all constructs compared with the A haplotype. The greatest reductions occurred with the F haplotype (+96, C→A) and the isolated polymorphism +209, both located near the SP1 protein-binding sites believed not to be active in vivo. These are the first analyses of α-MRE polymorphisms on gene expression and demonstrate that these single nucleotide polymorphisms, although outside the binding sites for nuclear factors, are able to influence in vitro gene expression. (AU)

Processo FAPESP: 02/13801-7 - Alterações hereditárias das hemoglobinas: genética molecular, aspectos da evolução clínica e produção de animais transgênicos
Beneficiário:Fernando Ferreira Costa
Linha de fomento: Auxílio à Pesquisa - Temático
Processo FAPESP: 03/07412-0 - Influência dos haplótipos do elemento regulatório do cluster alfa na expressão dos genes da globina alfa humana
Beneficiário:Daniela Maria Ribeiro
Linha de fomento: Bolsas no Brasil - Doutorado