Molecular characterization of a mouse genomic element mobilized by advanced glycation endproduct modified-DNA (AGE-DNA).
BACKGROUND
DNA modified by advanced glycation endproducts (AGEs) undergoes a high frequency of insertional mutagenesis. In mouse lymphoid cells, these mutations are due in part to the transposition of host genomic elements that contain a DNA region homologous to the Alu family of repetitive elements. One particular 853 bp insertion, designated INS-1, was identified previously as a DNA element common to plasmids recovered from multiple, independent lymphoid cell transfections.


METHODS
To characterize the genomic origin of this element, we used a 281-bp region of non-Alu-containing INS-1 sequence, designated. CORE, as a probe in Southern hybridization and for screening a bacteriophage mouse genomic DNA library. The resultant clones were sequenced and localized within the mouse genome.


RESULTS
Two distinct genomic clones of 15 kB and 17 kB in size were isolated. A 522-bp unique region common to INS-1 and corresponding to the CORE sequence was identified in each clone. In both cases, CORE was found to be surrounded by repetitive DNA sequences: a 339-bp MT repeat at the 5' end, and a 150-bp B1 repeat at the 3' end. The CORE sequence was localized to mouse chromosome 1.


CONCLUSIONS
These studies revealed that the CORE region of INS is present in low copy number but is associated with known repetitive DNA elements. The presence of these repetitive elements may facilitate the transposition of CORE by recombination or other, more complex rearrangement events, and explain in part the origin of AGE-induced insertional mutations.
Pushkarsky
T
T
Picower Institute for Medical Research, Manhasset, New York 11030, USA.
Rourke
L
L
Spiegel
L A
LA
Seldin
M F
MF
Bucala
R
R
D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002460:Cell Line; D002874:Chromosome Mapping; D004247:DNA / Q000032:analysis* / Q000378:metabolism; D004251:DNA Transposable Elements / Q000235:genetics*; D015698:Genomic Library; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D017422:Sequence Analysis, DNA
D004251:DNA Transposable Elements; D017127:Glycation End Products, Advanced; D004247:DNA