[Tissue-specific splicing of 5'-exons of the Oct-1 transcription factor gene]

It has been shown that pro-mRNA of transcription factor Oct-1 undergoes the tissue-specific splicing. The Oct-1L subform is synthesized in mouse lymphoid myeloma cells NS/0 of the B series and is not found in other somatic and embryonal cells. Initiation sites of oct-1R mRNA transcription are at positions -159 and -307 from the AUG codon of the oct-1R exon. In both cases, no TATA box was found in the region preceding these sites (25-30 bp). A different form of oct-1 mRNA (oct-1U) was also found in NS/0 cells, which is probably synthesized in all cell lines. This subform differs from oct-1R, in particular, by the structure of the 5T-terminal exon, which is the result of alternative splicing.