Visualization of transcription-dependent association of imprinted genes with the nuclear matrix.
Genomic imprinting is characterized by allele-specific gene expression as a biological phenomenon. To analyze the participation of the nuclear matrix in the expression of imprinted genes, we first examined the allelic expression state of genes by simultaneously visualizing their primary transcripts and the gene sequences in individual cell nuclei using fluorescence in situ hybridization (FISH). We confirmed that each imprinted gene, SNRPN and UBE3A in human lymphocytes and Igf2 and H19 in mouse embryonic fibroblasts, mainly expressed from one allele, although some nuclei showed biallelic expression. We next visualized the gene sequences on the nuclear matrix by FISH with a tyramide signal amplification technique. Interestingly, we predominantly observed one DNA signal of imprinted genes on the nuclear matrix preparation, closely correlated with their expression patterns. Using patient cells, we confirmed that both the transcription and the binding to the nuclear matrix of the SNRPN gene occurred at the paternal allele. Our results suggest that the nuclear matrix plays an important role in gene expression, including imprinted genes, and that the FISH technique used here allows us to visualize the behaviors of genes at an individual cell level.
Kagotani
Kazuhiro
K
Faculty of Bioresources, Mie University, 1515 Kamihama, Tsu, 514-8507, Japan.
Nabeshima
Hiroki
H
Kohda
Atsushi
A
Nakao
Mitsuyoshi
M
Taguchi
Hiroshi
H
Okumura
Katsuzumi
K
D000483:Alleles; D022981:Allelic Imbalance / Q000235:genetics*; D000818:Animals; D001324:Autoantigens / Q000235:genetics; D001483:Base Sequence / Q000235:genetics; D001665:Binding Sites / Q000235:genetics; D004247:DNA / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics*; D005796:Genes / Q000235:genetics*; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D015530:Nuclear Matrix / Q000235:genetics*; D012313:RNA / Q000235:genetics; D017411:Ribonucleoproteins, Small Nuclear; D014158:Transcription, Genetic / Q000235:genetics*; D055517:snRNP Core Proteins
D001324:Autoantigens; D017411:Ribonucleoproteins, Small Nuclear; C526417:SNRPN protein, human; D055517:snRNP Core Proteins; D012313:RNA; D004247:DNA