Cis-acting sequences from mouse rDNA promote plasmid DNA amplification and persistence in mouse cells: implication of HMG-I in their function.
Searching for amplification promoting sequences within the murine rDNA cistrons, we isolated two elements from the nontranscribed spacer region. These 370 bp and 423 bp long cis-acting elements, referred to as muNTS1 and muNTS2, are localized 4.1 kb and 4.6 kb upstream the RNA polymerase I transcriptional start site. They contain ca. 50 bp long AT-rich sequences that strongly interact with a protein from nuclear extracts. The protein could be purified and identified as HMG-I. A synthetic oligonucleotide encompassing the AT-rich stretch from muNTS1 is able to substitute for the muNTS elements. A similar sequence from the nontranscribed spacer of rat has previously been reported to be important for the function of the RNA polymerase I enhancer (1). Therefore the interaction of HMG I with the muNTS elements may play a role both in the stimulation of DNA amplification and transcription.
Wegner
M
M
Institut für Biochemie, Universität Würzburg, FRG.
Zastrow
G
G
Klavinius
A
A
Schwender
S
S
Müller
F
F
Luksza
H
H
Hoppe
J
J
Wienberg
J
J
Grummt
F
F
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D004275:DNA, Ribosomal / Q000235:genetics*; D005784:Gene Amplification; D005796:Genes; D006609:High Mobility Group Proteins / Q000378:metabolism*; D007739:L Cells / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012318:RNA Polymerase I / Q000378:metabolism; D015183:Restriction Mapping; D014158:Transcription, Genetic; D014162:Transfection
D004275:DNA, Ribosomal; D006609:High Mobility Group Proteins; D015345:Oligonucleotide Probes; D012318:RNA Polymerase I