Subnuclear localization of the active variant surface glycoprotein gene expression site in Trypanosoma brucei
| العنوان: | Subnuclear localization of the active variant surface glycoprotein gene expression site in Trypanosoma brucei |
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| المؤلفون: | Anton K. Raap, Anita Dirks-Mulder, Inês Chaves, Joost C. B. M. Zomerdijk, Piet Borst, Roeland W. Dirks |
| المصدر: | Proceedings of the National Academy of Sciences. 95:12328-12333 |
| بيانات النشر: | Proceedings of the National Academy of Sciences, 1998. |
| سنة النشر: | 1998 |
| مصطلحات موضوعية: | Genetic Markers, Nucleolus, Trypanosoma brucei brucei, Gene Expression, RNA polymerase II, Biology, DNA, Ribosomal, chemistry.chemical_compound, Transcription (biology), RNA polymerase, Gene expression, medicine, RNA polymerase I, Animals, In Situ Hybridization, Fluorescence, Cell Nucleus, Multidisciplinary, RNA, DNA Polymerase II, Biological Sciences, Immunohistochemistry, Molecular biology, Cell nucleus, medicine.anatomical_structure, chemistry, biology.protein, Poly(ADP-ribose) Polymerases, Variant Surface Glycoproteins, Trypanosoma |
| الوصف: | In Trypanosoma brucei , transcription by RNA polymerase II and 5′ capping of messenger RNA are uncoupled: a capped spliced leader is trans spliced to every RNA. This decoupling makes it possible to have protein-coding gene transcription driven by RNA polymerase I. Indeed, indirect evidence suggests that the genes for the major surface glycoproteins, variant surface glycoproteins (VSGs) in bloodstream-form trypanosomes, are transcribed by RNA polymerase I. In a single trypanosome, only one VSG expression site is maximally transcribed at any one time, and it has been speculated that transcription takes place at a unique site within the nucleus, perhaps in the nucleolus. We tested this by using fluorescence in situ hybridization. With probes that cover about 50 kb of the active 221 expression site, we detected nuclear transcripts of this site in a single fluorescent spot, which did not colocalize with the nucleolus. Analysis of marker gene-tagged active expression site DNA by fluorescent DNA in situ hybridization confirmed the absence of association with the nucleolus. Even an active expression site in which the promoter had been replaced by an rDNA promoter did not colocalize with the nulceolus. As expected, marker genes inserted in the rDNA array predominantly colocalize with the nucleolus, whereas the tubulin gene arrays do not. We conclude that transcription of the active VSG expression site does not take place in the nucleolus. |
| تدمد: | 1091-6490 0027-8424 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9f82ed2ada58aa67a0557bf89a07db96 https://doi.org/10.1073/pnas.95.21.12328 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....9f82ed2ada58aa67a0557bf89a07db96 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10916490 00278424 |
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