title: Characterization of a member of the highly repeated long interspersed rat DNA family with long open reading frames.
abstract: A highly repetitive long interspersed sequence from rat DNA has been isolated and partly characterized. This sequence comprises at least a 1300 base-pair and a 2400 base-pair EcoRI fragment and probably additional elements. The 2400 base-pair segment has been analyzed in detail. It appears to be part of the chromosomal DNA in rat cells. The 2400 base-pair repeat is likely to be distributed over several regions in the rat genome. The 2400 base-pair segment has been cloned, mapped for restriction sites, and part of its nucleotide sequence has been determined. The 2400 base-pair sequence is a member of a typical highly repetitive long interspersed sequence with high copy number and restriction site polymorphism. There are sequence homologies to mouse and human DNA. A striking homology has been detected to the flanking sequences of a repetitive mouse DNA sequence that has been described to be located adjacent to one of the kappa-immunoglobulin variable genes. Elements in the 2400 base-pair rat repeat are transcribed in cells from most rat organs and from several continuous rat cell lines. This RNA from rat cell lines was found polyadenylated or not polyadenylated. The nucleotide sequence of parts of the 2400 base-pair DNA segment revealed open reading frames for polypeptide sequences. Such open reading frames have been detected in two different segments of the 2400 base-pair DNA repeat. Open reading frames exist in the two complementary strands in the same DNA segment. The hypothetical polypeptide whose sequence has been determined in toto has a length of 190 amino acid residues and is enriched in hydrophobic amino acids, reminiscent of the amino acid composition in membrane proteins. Hence, it is conceivable that the 2400 base-pair repeat sequence from rat DNA, at least in part, encodes messenger RNAs that might be translated into functional proteins.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D006801:Humans; D051379:Mice; D010455:Peptides; D011110:Polymorphism, Genetic; D014176:Protein Biosynthesis; D051381:Rats; D012091:Repetitive Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
chemical_list: D010455:Peptides; D004247:DNA