Identification of the physiological promoter for spinocerebellar ataxia 2 gene reveals a CpG island for promoter activity situated into the exon 1 ofthis gene and provides data about the origin of the nonmethylated state ofthese types of islands

In order to further use the spinocerebellar ataxia 2 (SCA2) promoter for tr ansgenic mice models of "CAG repeat" neurodegeneration, different fragments of this 5' end were ligated into pGL3-Luc plasmid to obtain the better pro moter-activity of the physiological promoter for SCA2. Base-par composition of the SCA2-5' region, and promoter prediction algorithms such as TSSW and TSSG, together with the high firefly luciferase expression after 48 hours of transient transfection in mammalian cells lines, showed a typical CpG is land for promoter-activity, The promoter activity was specifically localize d into the exon 1 of the SCA2 gene. The higher expression of firefly lucife rase in the embryonal F9 cells by the use of SCA2 promoter, rather than by the use of CMV promoter may be related with the origin of the nonmethylated CpG island during the early embryogenesis. Analysis of the 5' region from HD gene revealed to a CpG island, which could be containing the physiologic al promoter for this gene. (C) 1999 Academic Press.