Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation

Immunoglobulin heavy chain (IGH) gene locus is expressed monoallelically in human B cells. Aim. To study the role of nuclear organization in regulation of the IGH expression during B-cell differentiation. Methods. Immunofluorescence in situ hybridization on 3D-preserved nuclei (3D immuno-FISH). Resu...

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Datum:2016
Hauptverfasser: Pichugin, A.V., Iarovaia, O.V., Sklyar, I.V., Lacombe, G., Razin, S.V., Fest, T., Lipinski, M., Vassetzky, Y.S.
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spelling nasplib_isofts_kiev_ua-123456789-1528272025-02-23T17:19:47Z Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation Внутрішньоядерна локалізація транскрипційних фабрик і алелей гену важкого ланцюгу імуноглобуліну в процесі дозрівання В-клітин людини Ядерная локализация транскрипционных фабрик и гена тяжелой цепи иммуноглобулина в процессе дифференцировки B-лимфоцитов Pichugin, A.V. Iarovaia, O.V. Sklyar, I.V. Lacombe, G. Razin, S.V. Fest, T. Lipinski, M. Vassetzky, Y.S. Structure and Function of Biopolymers Immunoglobulin heavy chain (IGH) gene locus is expressed monoallelically in human B cells. Aim. To study the role of nuclear organization in regulation of the IGH expression during B-cell differentiation. Methods. Immunofluorescence in situ hybridization on 3D-preserved nuclei (3D immuno-FISH). Results. Active RNA polymerase II (Pol II) molecules and the IGH locus were detected in the periphery of the nucleoli at some stages of B-cell differentiation. Conclusions. We observed significant changes in the pattern of distribution of RNA polymerase II in the nucleus during B-cell differentiation, but no preferential co-localization of the productive IGH allele with the transcription factories in the vicinity of the nucleolus and in the nucleoplasm was observed. Лише один аллель гену важкого ланцюгу імуноглобуліну (IGH) експресується в В -клітинах людини. Мета. Вивчити роль ядерної організації у регуляції експресії IGH при диференціюванні В-клітин. Методи. Імунофлуоресцентна гібридизація in situ (3D immuno-FISH). Результати. Активна форма РНК-полімерази II (Pol II) і ген IGH були виявлені на периферії ядерець на деяких стадіях диференціювання В-клітин. Висновки. Ми спостерігали значні зміни в характері розподілу РНК-полімерази II в ядрі під час диференціювання В-клітин. При цьому, не спостерігалося мажорної локалізації продуктивного алелі IGH з транскрипційними фабриками ні у безпосередній близькості від ядерець, ні в нуклеоплазмі. Лишь один аллель гена тяжелой цепи иммуноглобулина (IGH) экспрессируется в Б-клетках человека. Цель. Изучить роль ядерной организации в регуляции экспрессии IGH в процессе дифференцировки В-клеток. Методы. Иммунофлуоресцентная гибридизация in situ (3D immuno-FISH). Результаты. Активная форма РНК-полимеразы II (Pol II) и ген IGH были обнаружены на периферии ядрышек на некоторых стадиях дифференцировки В-клеток. Выводы. Мы наблюдали значительные изменения в характере распределения РНК-полимеразы II в ядре во время дифференцировки В-клеток. При этом, не наблюдалось премущественной локализации продуктивного аллеля IGH с транскрипционными фабриками ни в непосредственной близости от ядрышек, ни в нуклеоплазме. This work was supported by the grant #14-24-00022 Russian Science Foundation (RSF). 2016 Article Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation / A.V. Pichugin, O.V. Iarovaia, I.V. Sklyar, G. Lacombe, S.V. Razin, T. Fest, M. Lipinski, Y.S. Vassetzky // Вiopolymers and Cell. — 2016. — Т. 32, № 3. — С. 179-183. — Бібліогр.: 18 назв. — англ. 0233-7657 DOI: http://dx.doi.org/10.7124/bc.00091C https://nasplib.isofts.kiev.ua/handle/123456789/152827 577 en Вiopolymers and Cell application/pdf Інститут молекулярної біології і генетики НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
topic Structure and Function of Biopolymers
Structure and Function of Biopolymers
spellingShingle Structure and Function of Biopolymers
Structure and Function of Biopolymers
Pichugin, A.V.
Iarovaia, O.V.
Sklyar, I.V.
Lacombe, G.
Razin, S.V.
Fest, T.
Lipinski, M.
Vassetzky, Y.S.
Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
Вiopolymers and Cell
description Immunoglobulin heavy chain (IGH) gene locus is expressed monoallelically in human B cells. Aim. To study the role of nuclear organization in regulation of the IGH expression during B-cell differentiation. Methods. Immunofluorescence in situ hybridization on 3D-preserved nuclei (3D immuno-FISH). Results. Active RNA polymerase II (Pol II) molecules and the IGH locus were detected in the periphery of the nucleoli at some stages of B-cell differentiation. Conclusions. We observed significant changes in the pattern of distribution of RNA polymerase II in the nucleus during B-cell differentiation, but no preferential co-localization of the productive IGH allele with the transcription factories in the vicinity of the nucleolus and in the nucleoplasm was observed.
format Article
author Pichugin, A.V.
Iarovaia, O.V.
Sklyar, I.V.
Lacombe, G.
Razin, S.V.
Fest, T.
Lipinski, M.
Vassetzky, Y.S.
author_facet Pichugin, A.V.
Iarovaia, O.V.
Sklyar, I.V.
Lacombe, G.
Razin, S.V.
Fest, T.
Lipinski, M.
Vassetzky, Y.S.
author_sort Pichugin, A.V.
title Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
title_short Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
title_full Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
title_fullStr Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
title_full_unstemmed Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation
title_sort intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human b-cell maturation
publisher Інститут молекулярної біології і генетики НАН України
publishDate 2016
topic_facet Structure and Function of Biopolymers
url https://nasplib.isofts.kiev.ua/handle/123456789/152827
citation_txt Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation / A.V. Pichugin, O.V. Iarovaia, I.V. Sklyar, G. Lacombe, S.V. Razin, T. Fest, M. Lipinski, Y.S. Vassetzky // Вiopolymers and Cell. — 2016. — Т. 32, № 3. — С. 179-183. — Бібліогр.: 18 назв. — англ.
series Вiopolymers and Cell
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fulltext 179 A. Pichugin, O. Iarovaia, I. Sklyar © 2016 A. Pichugin et al.; Published by the Institute of Molecular Biology and Genetics, NAS of Ukraine on behalf of Biopolymers and Cell. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited UDC 577 Intranuclear localization of transcription factories and immunoglobulin heavy chain gene alleles during human B-cell maturation A.V. Pichugin1,2,3, O. V. Iarovaia1,2,4, I. V. Sklyar1,2,4, G. Lacombe5, S. V. Razin2,4,6, T. Fest5, M. Lipinski1,2, Y. S. Vassetzky1,2,6 1 CNRS UMR 8126, Universit Paris-Sud 11, Institut Gustave Roussy 114, rue Edouard Vaillant, Villejuif, France, 94805 2 LIA 1066 French-Russian Joint Cancer Research Laboratory Villejuif, France–Moscow, Russian Federation 3 Peter the Great St. Petersburg Polytechnic University 29, Polytechnicheskaya Str, St.Petersburg, Russian Federation, 195251 4 Institute of Gene Biology, Russian Academy of Sciences 34/5, Vavilova Str., Moscow, Russian Federation, 119334 5 INSERM U917, Université de Rennes 2, avenue du Professeur Léon Bernard F - 35043 Rennes, France 6 Faculty of Biology, M. V. Lomonosov Moscow State University Leninskie Gory, Moscow, Russian Federation, 119991 vassetzky@igr.fr Immunoglobulin heavy chain (IGH) gene locus is expressed monoallelically in human B cells. Aim. To study the role of nuclear organization in regulation of the IGH expression during B-cell differentiation. Methods. Immuno- fluorescence in situ hybridization on 3D-preserved nuclei (3D immuno-FISH). Results. Active RNA polymerase II (Pol II) molecules and the IGH locus were detected in the periphery of the nucleoli at some stages of B-cell differentiation. Conclusions. We observed significant changes in the pattern of distribution of RNA polymerase II in the nucleus during B-cell differentiation, but no preferential co-localization of the productive IGH allele with the transcription factories in the vicinity of the nucleolus and in the nucleoplasm was observed. K e y w o r d s: Immunoglobulin heavy chain gene, transcription, nucleolus, B-cell maturation Introdution Nucleus is divided into transcriptionally active and repressive compartments (reviewed in [1]). Transcriptional activation is associated with the eu- chromatic regions of the nucleus and transcriptional factories (reviewed in [2]). A functional immuno- globulin heavy chain is produced monoallelically (Rajewsky 1996); it undergoes regulated transcrip- tion during the B lymphocyte development. Transcription might be controlled by localized al- terations in the chromatin structure. Whether such a mechanism is sufficient to account for the allele-spe- cific transcription of the IGH locus is currently un- known. In mice, the localization of productive and non-productive IGH alleles changes during B-cell maturation. A non-productive IGH allele is located close to the nuclear periphery whereas the produc- tive IGH allele is associated with euchromatin [5–7]; much less is known about the role of nuclear organi- zation in the human IGH allelic transcription. We have recently found that the IGH locus was located ISSN 1993-6842 (on-line); ISSN 0233-7657 (print) Biopolymers and Cell. 2016. Vol. 32. N 3. P 179–183 doi: http://dx.doi.org/10.7124/bc.00091C 180 A. Pichugin, O. Iarovaia, I. Sklyar et al. close to the nucleolus in both naïve and activated B-cells [8] as well as in B-cell lymphoma [9]. However, the functional significance of this localiza- tion remains unknown. Given the evidence that the eukaryotic gene acti- vity can be regulated by subnuclear compartmenta- lization (reviewed in [10]), we investigated whether the perinucleolar localization of the IGH locus might play a role in controlling its transcription. Here we have used 3D-fluorescence in situ hybridization (3D-FISH) combined with immunofluorescence to co-detect the localization of the IGH alleles, nucleo- li and transcription factories at different stages of B lymphocyte maturation. Materials and Methods In vitro B-cell differentiation Peripheral blood cells from healthy volunteers were purchased from the French Blood Center. B-cells at different stages of differentiation were obtained es- sentially as described in [11]. Plasmocytes were iso- lated from peripheral blood using the CD138+ Plasma Cell Isolation Kit (Miltenyi Biotech). Three-dimensional fluorescence in situ hybridi- zation (3D-FISH) and immuno-detection 3D FISH experiments were essentially carried out as described elsewhere [9]. The stained probes used in this study (RP11-346I20 that recognizes the constant region of the IGH locus and RP11-259B19 for the J/D region) were purchased from Blue Gnome (Cambridge, UK). Nucleoli were detected using mouse anti-B23 antibody (Sigma, St Louis, MO) and chicken anti-mouse Alexa 647 (Molecular Probes, Carlsbad, CA). The Pol II antibodies were from Active Motif, Carlsbad, CA. The images were processed and analyzed as described in [9]. Results and Discussion In order to study whether the IGH localization vs. transcription factories undergoes dynamic changes linked to its functional status, we have followed the localization of the IGH alleles in human cells during B-cell maturation in vitro [11]; this system allows reproducing the major stages of B-cell differentia- tion in lymph nodes. We used B-cells at the follow- ing stages: naive B-cells (Day0), activated B-cells (Day1), cells at the stage of plasmoblast differentia- tion (Day4), and cells at the stage of somatic hyper- mutation and class switch recombination (Day5/6). The IGH locus being located close to a nucleolus at some stages of B-cell maturation [8], we wondered whether its transcription would actually take place in the perinucleolar region which, with some exceptions [9] is not known for being prone to [the] RNA poly- merase II (Pol II)-dependent gene transcription [12]. To test this, B-cells were stained using the B23 anti- body that decorates nucleoli and the antibody to the phosphorylated C-terminal domain of the transcrip- tionally-active form of Pol II. These active Pol II molecules are present in nuclear foci called transcrip- tion factories, where active transcription takes place (for review see [2]). Typical Pol II staining patterns are presented in Fig. 1. Uniform staining of active Pol II molecules was detected in the immediate vicinity of nucleoli in naïve B lymphocytes at Day0. Activation of B-cells at Day1 led to a decrease in Pol II staining with transcription factories being organized in clus- ters, some of them adjacent to the nucleolus. At Day4, Pol II was excluded from the perinucleolar regions; at Day5/6, this exclusion zone disappeared and intense Pol II staining surrounded the nucleolus. Finally, in plasmocytes, Pol II staining concentrated in the cen- ter of the nucleus, with some staining around the nu- cleolus (Fig. 1). Next, the proximity between the IGH alleles and Pol II foci at different stages of B-cell differentiation was evaluated using an immuno-FISH approach whereby nucleoli, Pol II clusters, and the productive IGH alleles were all simultaneously visualized. [The] Signals from the productive IGH allele (green), and Pol II (white) were scored in relation to their proxim- ity to the nucleolus (blue). The results are summarized in Fig. 2. These data indicate that the productive IGH allele is preferentially colocalized with the transcrip- tion factories at the nucleolus in naïve B-lymphocytes at Day0 and at the SHM and CSR stages at Day5/6. 181 Intranuclear localization of transcription factories and IGH gene alleles during human B-cell maturation B-cells are monospecific, i.e. they produce one anti- body per cell. This is due to allelic exclusion of im- munoglobulin (Ig) heavy (H) and light (L) chain genes established during V(D)J recombination (reviewed in [13]). While the somatic generation of functional Ig genes by V(D)J recombination is a subject to allelic exclusion, the expression of Ig loci per se does not ap- pear to be monoallelic as Ig transcripts are expressed from both alleles whereas only one of the two Ig al- leles is functional [14]. The molecular and cellular mechanisms regulating allelic exclusion during V(D)J recombination are well studied [15], much less is known on how these mechanisms operate at the final stages of B-cell differentiation. DNA methylation [16], chromatin organization [17] and subnuclear localiza- tion [5–8] might contribute to this process. The positioning of one allele in the vicinity of a nucleolus, a statistically significant difference be- Fig. 2. Association of IGH al- leles with the RNA poly- merase II during B-cell matu- ration. A, quantitation of co- localization of the productive (red) and non-productive (blue) IGH alleles with the nucleolus and transcription factories. B, Representative images of the productive (green) and non-productive (merged green and red) IGH alleles with nuclei stained for nucleolus (bleu) and RNA polymerase II (gray) at differ- ent stages of B-cell matura- tion. Scale bar=5µm and 1µm in zoom. Fig. 1. Localization of transcription factories and nucleoli during induced B-cell maturation. Active RNA polymerase II (green) and nucleoli (B23, blue) were simultaneously revealed by immunostaining. Typical images are shown. Scale bar=5µm 182 A. Pichugin, O. Iarovaia, I. Sklyar et al. tween the two alleles, may be linked to the IGH ex- pression. Indeed, transcriptionally active Pol II clus- ters could be observed in the vicinity of the nucleolus in lymphoid cells [9]. It is also known that nuclear factors localized in and around the nucleolus, such as nucleolin, are essential for [the] IGH transcription [18]. Using immuno-FISH experiments, we analyzed the localization of the two alleles with clusters of transcriptionally active Pol II molecules (transcrip- tion factories, see [2] for review). We could not ob- serve any preferential localization of the productive IGH allele with the transcription factories in the vi- cinity of the nucleolus and in the nucleoplasm. At the same time, the pattern of distribution of RNA poly- merase II changed during B cell maturation, with the most striking feature being the exclusion of active RNA Pol II molecules from the perinucleolar region in activated B cells at Day4. We have also detected the presence of active Pol II clusters in the periphery of nucleoli that in normal cells is mostly occupied by heterochromatin [12] and therefore is not prone to the Pol II transcription. Further studies are necessary to establish a link between transcriptional activity and subnuclear organization of the IGH alleles. 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Transcriptional activation by LR1 at the Emu enhancer and switch region sites. Nucleic Acids Res. 2000;28(14):2651–7. Внутрішньоядерна локалізація транскрипційних фабрик і алелей гену важкого ланцюгу імуноглобуліну в процесі дозрівання В-клітин людини А. В. Пичугін, О. В. Ярова, І. В. Скляр, Г. Лякомб, С. В. Разин, Т. Фест, М. Липинскій, Є. С. Васецький Лише один аллель гену важкого ланцюгу імуноглобуліну (IGH) експресується в В-клітинах людини. Мета. Вивчити роль ядер- ної організації у регуляції експресії IGH при диференціюванні В-клітин. Методи. Імунофлуоресцентна гібридизація in situ (3D immuno-FISH). Результати. Активна форма РНК-полі ме- ра зи II (Pol II) і ген IGH були виявлені на периферії ядерець на деяких стадіях диференціювання В-клітин. Висновки. Ми спостерігали значні зміни в характері розподілу РНК-полі ме- ра зи II в ядрі під час диференціювання В-клітин. При цьому, не спостерігалося мажорної локалізації продуктивного алелі IGH з транскрипційними фабриками ні ву безпосередній близькості від ядерець, ні в нуклеоплазмі. К л юч ов і с л ов а: гени важких ланцюгів імуноглобуліну, транскрипція, ядро, дозрівання B-клітин Внутриядерная локализация транскрипционных фабрик и аллелей гена тяжелой цепи иммуноглобулина в процессе созревания В-клеток человека А. В. Пичугин, О. В. Яровая, И. В. Скляр, Г. Лякомб, С. В. Разин, Т. Фест, М. Липинский, Е. С. Васецкий Лишь один аллель гена тяжелой цепи иммуноглобулина (IGH) экспрессируется в Б-клетках человека. Цель. Изучить роль ядерной организации в регуляции экспрессии IGH в процессе дифференцировки В-клеток. Методы. Иммунофлуоресцентная гибридизация in situ (3D immuno-FISH). Результаты. Активная форма РНК-полимеразы II (Pol II) и ген IGH были обнаружены на периферии ядрышек на некоторых стадиях дифференци- ровки В-клеток. Выводы. Мы наблюдали значительные изме- нения в характере распределения РНК-полимеразы II в ядре во время дифференцировки В-клеток. При этом, не наблюдалось премущественной локализации продуктивного аллеля IGH с транскрипционными фабриками ни в непосредственной бли- зости от ядрышек, ни в нуклеоплазме. К л юч е в ы е с л ов а: гены тяжелых цепей иммуноглобули- на, транскрипция, ядро, дозревание B-клеток Received 14.02.2016