ANALYSIS OF HOMOLOGOUS DNA-SEQUENCES WITH IN THE FIRST INTRON OF THE MOUSE-HUMAN MTS1 GENES - KB-LIKE SITE AND MICROSATELLITE DNA

Homologous regions were revealed and analyzed within the first intron of the mouse and human mts1 genes. Maximal homology was detected betwe en microsatellite DNA sequences from the first intron of the mouse gen e (+804, +863) and the human gene (+-600, +645). DNase I hypersensitiv e sites were revealed within these regions in both mouse and human cel l lines tested, thus showing functional significance of the homology d etected. In both the mouse and the human genes, the 5' end of homologo us regions is flanked by a DNA sequence similar to a NF-kB/Rel protein -binding consensus sequence. Previously, this sequence was demonstrate d to be involved in a complex regulatory element of the mouse mts1 gen e. In comparison with the kB-like sequence, mouse, rat, and human sequ ences were found to involve one, two, and three nucleotide substitutio ns, respectively. Alterations in a spectrum of nuclear proteins bound to various kB-like sequences were analyzed. Possible effects of these alterations on mts1 transcription regulation were discussed. The possi bility of the human kB-like sequence to function as positive regulator of transcription initiation was demonstrated in vivo.