Transcriptional promoter and enhancer elements in the long terminal repeats (LTR) of endogenous murine leukemia virus (MuLV)-related proviral sequences
Mouse genome harbors 2 families of MuLV-related proviral sequences, which do not directly produce infectious virus, but may express RNA transcripts in a tissue-specific manner. The LTRS of MuLV-related sequences contain a mid-U3 inserted segment (IS) of approx. 200 bp not found in the LTR of infectious MuLVs. To test for the LTR promoter and enhancer activities, chloramphenicol acetyltransferase (CAT) gene, alone or carrying SV40 promoter, was linked to various LTR sequences of 2 MuLV and 6 representative MuLV-related DNA clones and the recombinant genes were examined for transient CAT expression in mouse NIH-3T3, mink CCL64 and human HT1080 cells by DNA transfection. While the CAT expression was high with the 2 ecotropic MuLV LTRs, very little to undetectable activities were obtained with all MuLV-related LTRs. To determine the basis for the very low activity of the MuLV-related LTRs, series of experiments were performed, which indicate that the TATA- and CCAAC-containing domain, downstream of the IS, is functionally intact as a promoter and that the IS sequences, while inactive as a promoter by itself, could provide a bi-directional enhancer-like activity to its own or MuLV LTR or SV40 promoter. Further studies suggest the presence of a cis-acting negative regulatory element in sequences upstream of the IS in both the 2 subfamilies of MuLV-related LTRs.
- Research Organization:
- Oak Ridge National Lab., TN
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 6025570
- Report Number(s):
- CONF-870644-
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
- Country of Publication:
- United States
- Language:
- English
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RNA
TRANSCRIPTION
VIRUSES
DNA SEQUENCING
FIBROBLASTS
GENE REGULATION
GENES
LEUKEMIA
MAMMALS
MAN
MICE
WILD ANIMALS
ANIMAL CELLS
ANIMALS
CONNECTIVE TISSUE CELLS
DISEASES
HEMIC DISEASES
MICROORGANISMS
NEOPLASMS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PARASITES
PRIMATES
RODENTS
SOMATIC CELLS
STRUCTURAL CHEMICAL ANALYSIS
VERTEBRATES
550200* - Biochemistry