The organization of the human myelin basic protein gene. Comparison with the mouse gene.

The organization of the gene of the human myelin basic protein has been established. The gene contains seven exons distributed over 32-34 kb. The nucleotide sequences of the seven exons, extensive parts at the 5' noncoding region and upstream and downstream regions adjacent to the exons were sequenced. A comparison of the nucleotide sequence of the human gene with mouse MBP cDNA and parts of the gene structure of mouse MBP has been carried out. There is a high degree of conservation in the seven exons and the 5'-regulatory and part of the 3'-noncoding region: the nucleotide sequence of the coding region of the human and mouse gene show a 93% homology. As far as the reported 5'-noncoding and upstream regulatory regions of 478 bp are comparable these regions are more than 80% homologous. Primer extension experiments positioned the transcription initiation sites at -55, -82 and -183. In the 5'-regulatory region of MBP gene three direct repeats were found, a nonameric at -401/-416 and two octameric at -192/-216 and -492/-508. A decameric sequence (-256 to -265 from the translation start) is completely homologous to a sequence of the human PLP regulatory 5'-noncoding region.