title: Conservation in the 5' region of the long interspersed mouse L1 repeat: implications of comparative sequence analysis.
abstract: A clone of 7.1kb corresponding to the mouse L1 interspersed repeat family was selected for homology to a human interspersed repeat. This clone fairly represents mouse genomic members. Mapping of the clone revealed one common element at both the 5' and 3' ends in a head to tail arrangement, suggesting that at least some long L1 family members are tandemly arranged; genomic studies confirmed the unexpected tandem arrangement of a minor proportion of L1 members. A short SmaI tandem repeat appears to define the 5' end of most L1 family members. SmaI repeats may maintain, via a recursive regulatory function, the transcriptional viability of L1 members after retroposition events. A 2.5kb portion of the mouse L1 repeat that has not been previously sequenced is presented. It is 55-70% homologous to a corresponding portion of the human KpnI repeat family. Comparative sequence analysis revealed that one common open reading frame may conserve potential coding function across species. A second open reading frame bears an asymmetric distribution of codon replacements unlike both genes and pseudogenes. This latter feature could be consistent with a proposed chromosome organization function that is unrelated to peptide expression.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes / Q000378:metabolism; D015246:Deoxyribonuclease EcoRI; D015247:Deoxyribonuclease HindIII; D015252:Deoxyribonucleases, Type II Site-Specific; D006801:Humans; D008099:Liver / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids; D011817:Rabbits; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004262:DNA Restriction Enzymes; D015246:Deoxyribonuclease EcoRI; D015247:Deoxyribonuclease HindIII; C025651:CCCGGG-specific type II deoxyribonucleases; C046545:CCWGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific