Evidence for uniparental, paternal expression of the human GABAA receptor subunit genes, using microcell-mediated chromosome transfer.
We have constructed mouse A9 hybrids containing a single normal human chromosome 15, via microcell-mediated chromosome transfer. Cytogenetic and DNA-polymorphic analyses identified mouse A9 hybrids that contained either a paternal or maternal human chromosome 15. Paternal specific expression of the known imprinted genes SNRPN (small nuclear ribonucleoprotein-associated polypeptide N gene) and IPW (imprinted gene in the Prader-Willi syndrome region) was maintained in the A9 hybrids. Using this system, we first demonstrated that human GABAAreceptor subunit genes, GABRB3 , GABRA5 and GABRG3 , were expressed exclusively from the paternal allele and that E6-AP (E6-associated protein or UBE3A ) was biallelically expressed. Moreover, the 5' portion of the GABRB3 gene was found to be hypermethylated on the paternal allele. Our data imply that GABAAreceptor subunit genes are imprinted and are possible candidates for Prader-Willi syndrome, and that this human monochromosomal hybrid system enables the efficient analysis of imprinted loci.
Meguro
M
M
Department of Molecular and Cell Genetics, School of Life Sciences, Faculty of Medicine, Tottori University, Nishimachi 86, Yonago, Tottori 683, Japan.
Mitsuya
K
K
Sui
H
H
Shigenami
K
K
Kugoh
H
H
Nakao
M
M
Oshimura
M
M
D000328:Adult; D000818:Animals; D001324:Autoantigens / Q000737:chemistry / Q000235:genetics; D002469:Cell Separation; D002478:Cells, Cultured; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D005260:Female; D005347:Fibroblasts; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D018392:Genomic Imprinting; D006801:Humans; D006822:Hybrid Cells; D008025:Ligases / Q000235:genetics; D008297:Male; D051379:Mice; D016133:Polymerase Chain Reaction; D011218:Prader-Willi Syndrome / Q000235:genetics; D011963:Receptors, GABA-A / Q000235:genetics*; D017411:Ribonucleoproteins, Small Nuclear / Q000235:genetics; D044767:Ubiquitin-Protein Ligases; D055517:snRNP Core Proteins
D001324:Autoantigens; D011963:Receptors, GABA-A; D017411:Ribonucleoproteins, Small Nuclear; C526417:SNRPN protein, human; D055517:snRNP Core Proteins; C471639:UBE3A protein, human; D044767:Ubiquitin-Protein Ligases; D008025:Ligases