title: Identification of transcriptional regulatory activity within the 5' A-type monomer sequence of the mouse LINE-1 retroposon.
abstract: LINE-1 (L1) is a retroposon found in all mammals. In the mouse, approximately 10% of L1 elements are full-length and can be grouped into two classes, A or F, based upon the type of monomer sequence repeated at the 5' end. In order to test for promoter activity in the 5' end of the A-type mouse L1 element, we cloned several different A-monomers into a promoterless chloramphenicol acetyltransferase (CAT) vector. The A-monomer constructs varied in their ability to regulate transcription of the CAT gene, exhibiting CAT activity 16-37% of that detected with the Rous sarcoma virus promoter and enhancer. A series of A-monomer deletions were tested for their ability to regulate CAT expression and gel retardation experiments were performed to identify regions of the A-monomer that may be involved in L1 transcriptional regulation. A-monomer sequences are usually found repeated 2-5 times at the 5' end of a full-length mouse L1. In the absence of long terminal repeats or an internal promoter, the tandem array of A-monomers may provide a mechanism for A-type L1 elements to generate transcripts containing transcriptional regulatory sequences.
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina, Chapel Hill 27599.
authors.forename: D M
authors.initials: DM
authors.lastname: Severynse
authors.forename: C A
authors.initials: CA
authors.lastname: Hutchison
authors.forename: M H
authors.initials: MH
authors.lastname: Edgell
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004247:DNA; D004251:DNA Transposable Elements / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D012045:Regulatory Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D004247:DNA