Directing DNA methylation to inhibit gene expression.
: 1. DNA methylation is a critical epigenetic modification that silences gene transcription, participates in X-chromosome inactivation in females, and regulates genomic imprinting. 2. We have devised a method to inhibit transcriptional initiation by constructing short methylated oligonucleotides which induce DNA methylation at specific loci. 3. The methodology by which we devise these oligonucleotides is described, using oligonucleotides directed against the oncogene, Bcl-2.4. The human Bcl-2 gene contains two promoters, each of which contains a CpG island in its core region. Oligonucleotides are designed which can inhibit Bcl-2 transcription and lead to decreased mRNA and protein in vitro. When compared to standard anti-sense oligonucleotide action, these methylated oligonucleotides are far more sensitive and potentially, longer acting. 5. In principle, using this methodology, it should be possible to design methylated oligonucleotides that can methylate CpG islands and thereby downregulate any gene.
Hoffman
Andrew R
AR
Department of Medicine, Stanford University, Medical Service, VA Palo Alto Health Care System, Miranda Ave., Palo Alto, California 94304, USA. arhoffman@stanford.edu
Hu
Ji Fan
JF
D000818:Animals; D001483:Base Sequence; D019175:DNA Methylation; D005786:Gene Expression Regulation; D020868:Gene Silencing; D019254:Genes, bcl-2; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D007335:Insulin-Like Growth Factor II; D008954:Models, Biological; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000235:genetics; D011506:Proteins / Q000235:genetics
C035170:IGF2 protein, human; D011506:Proteins; D007335:Insulin-Like Growth Factor II