Characterization of enhancer elements in the long terminal repeat of Moloney murine sarcoma virus.
AUTOR(ES)
Laimins, L A
RESUMO
A series of recombinant molecules were constructed which direct the expression of the easily assayed gene chloramphenicol acetyltransferase. We have used these recombinants to show that the 73/72-base-pair tandem repeat unit from the Moloney murine sarcoma virus long terminal repeat shares a number of properties with the prototypic enhancer element, the simian virus 40 72-base-pair repeat. Specifically, the Moloney murine sarcoma virus sequence significantly enhances the level of gene expression at both 5' and 3' locations and in either orientation relative to the test gene. It is able to enhance gene activity both from its own promoter and from a heterologous (simian virus 40) promoter. The 73/72-base-pair subunits of the Moloney murine sarcoma virus enhancer differ in sequence by four nucleotides and also in the strength of their enhancer function. The promoter distal A repeat is at least three times as active as the promoter proximal B repeat in enhancing chloramphenicol acetyltransferase expression. Results of these studies also show that the enhancer sequence alone is unable to induce gene activity but requires other promoter elements, including a proximal GC-rich sequence and the Goldberg-Hogness box.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=255440Documentos Relacionados
- Identification of transcriptional elements within the long terminal repeat of Rous sarcoma virus.
- Delineation of transcriptional control signals within the Moloney murine sarcoma virus long terminal repeat.
- Alternate utilization of two regulatory domains within the Moloney murine sarcoma virus long terminal repeat.
- Deletion of a GC-rich region flanking the enhancer element within the long terminal repeat sequences alters the disease specificity of Moloney murine leukemia virus.
- Characterization of nuclear proteins that bind the EFII enhancer sequence in the Rous sarcoma virus long terminal repeat.