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Joanna M Bridger - One of the best experts on this subject based on the ideXlab platform.
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interphase Chromosome Positioning in in vitro porcine cells and ex vivo porcine tissues
BMC Cell Biology, 2012Co-Authors: Helen A Foster, Darren K Griffin, Joanna M BridgerAbstract:In interphase nuclei of a wide range of species Chromosomes are organised into their own specific locations termed territories. These Chromosome territories are non-randomly positioned in nuclei which is believed to be related to a spatial aspect of regulatory control over gene expression. In this study we have adopted the pig as a model in which to study interphase Chromosome Positioning and follows on from other studies from our group of using pig cells and tissues to study interphase genome re-Positioning during differentiation. The pig is an important model organism both economically and as a closely related species to study human disease models. This is why great efforts have been made to accomplish the full genome sequence in the last decade. This study has positioned most of the porcine Chromosomes in in vitro cultured adult and embryonic fibroblasts, early passage stromal derived mesenchymal stem cells and lymphocytes. The study is further expanded to position four Chromosomes in ex vivo tissue derived from pig kidney, lung and brain. It was concluded that porcine Chromosomes are also non-randomly positioned within interphase nuclei with few major differences in Chromosome position in interphase nuclei between different cell and tissue types. There were also no differences between preferred nuclear location of Chromosomes in in vitro cultured cells as compared to cells in tissue sections. Using a number of analyses to ascertain by what criteria porcine Chromosomes were positioned in interphase nuclei; we found a correlation with DNA content.
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rapid Chromosome territory relocation by nuclear motor activity in response to serum removal in primary human fibroblasts
Genome Biology, 2010Co-Authors: Ishita S Mehta, Manelle Amira, Amanda J Harvey, Joanna M BridgerAbstract:Background Radial Chromosome Positioning in interphase nuclei is nonrandom and can alter according to developmental, differentiation, proliferation, or disease status. However, it is not yet clear when and how Chromosome rePositioning is elicited.
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rapid Chromosome territory relocation by nuclear motor activity in response to serum removal in primary human fibroblasts
Genome Biology, 2010Co-Authors: Ishita S Mehta, Manelle Amira, Amanda J Harvey, Joanna M BridgerAbstract:Radial Chromosome Positioning in interphase nuclei is nonrandom and can alter according to developmental, differentiation, proliferation, or disease status. However, it is not yet clear when and how Chromosome rePositioning is elicited. By investigating the Positioning of all human Chromosomes in primary fibroblasts that have left the proliferative cell cycle, we have demonstrated that in cells made quiescent by reversible growth arrest, Chromosome Positioning is altered considerably. We found that with the removal of serum from the culture medium, Chromosome rePositioning took less than 15 minutes, required energy and was inhibited by drugs affecting the polymerization of myosin and actin. We also observed that when cells became quiescent, the nuclear distribution of nuclear myosin 1β was dramatically different from that in proliferating cells. If we suppressed the expression of nuclear myosin 1β by using RNA-interference procedures, the movement of Chromosomes after 15 minutes in low serum was inhibited. When high serum was restored to the serum-starved cultures, Chromosome rePositioning was evident only after 24 to 36 hours, and this coincided with a return to a proliferating distribution of nuclear myosin 1β. These findings demonstrate that genome organization in interphase nuclei is altered considerably when cells leave the proliferative cell cycle and that rePositioning of Chromosomes relies on efficient functioning of an active nuclear motor complex that contains nuclear myosin 1β.
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non random Chromosome Positioning in mammalian sperm nuclei with migration of the sex Chromosomes during late spermatogenesis
Journal of Cell Science, 2005Co-Authors: Helen A Foster, Darren K Griffin, Lalantha R Abeydeera, Joanna M BridgerAbstract:Chromosomes are highly organized and compartmentalized in cell nuclei. The analysis of their position is a powerful way to monitor genome organization in different cell types and states. Evidence suggests that the organization of the genome could be functionally important for influencing different cellular and developmental processes, particularly at early stages of development (i.e. fertilization and the consequent entry of the sperm nucleus into the egg). The position of Chromosomes in the sperm nucleus might be crucial, because their location could determine the time at which particular chromatin domains are decondensed and remodelled, allowing some epigenetic level of control or influence over subsequent paternal gene expression in the embryo. Here, we analyse genome organization by Chromosome position in mammalian sperm nuclei from three breeds of pig, as a model species. We have mapped the preferential position of all Chromosomes (bar one) in sperm nuclei in two dimensions and have established that the sex Chromosomes are the most internally localized Chromosomes in mature sperm. The distribution of two autosomes and Chromosomes X and Y in sperm heads was compared in primary and secondary spermatocytes and spermatids in porcine testes. The sex Chromosomes were found at the nuclear edge in primary spermatocytes, which correlates with the known position of the XY body and their position in somatic cells, whereas, in spermatids, the sex Chromosomes were much more centrally located, mirroring the position of these Chromosomes in ejaculated spermatozoa. This study reveals the temporal rePositioning of Chromosome territories in spermatogenesis.
Maciej Kurpisz - One of the best experts on this subject based on the ideXlab platform.
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Chromosome re Positioning in spermatozoa of fathers and sons carriers of reciprocal Chromosome translocation rct
BMC Medical Genomics, 2019Co-Authors: Marta Olszewska, Alina T. Midro, Ewa Wiland, Nataliya Huleyuk, Monika Fraczek, Danuta Zastavna, Maciej KurpiszAbstract:Non-random Chromosome Positioning has been observed in the nuclei of several different tissue types, including human spermatozoa. The nuclear arrangement of Chromosomes can be altered in men with decreased semen parameters or increased DNA fragmentation and in males with chromosomal numerical or structural aberrations. An aim of this study was to determine whether and how the Positioning of nine Chromosome centromeres was (re)arranged in the spermatozoa of fathers and sons – carriers of the same reciprocal Chromosome translocation (RCT). Fluorescence in situ hybridization (FISH) was applied to analyse the Positioning of sperm Chromosomes in a group of 13 carriers of 11 RCTs, including two familial RCT cases: t(4;5) and t(7;10), followed by analysis of eight control individuals. Additionally, sperm chromatin integrity was evaluated using TUNEL and Aniline Blue techniques. In the analysed familial RCT cases, rePositioning of the Chromosomes occurred in a similar way when compared to the data generated in healthy controls, even if some differences between father and son were further observed. These differences might have arisen from various statuses of sperm chromatin disintegration. Nuclear topology appears as another aspect of epigenetic genomic regulation that may influence DNA functioning. We have re-documented that chromosomal Positioning is defined in control males and that a particular RCT is reflected in the individual pattern of chromosomal topology. The present study examining the collected RCT group, including two familial cases, additionally showed that chromosomal factors (karyotype and hyperhaploidy) have superior effects, strongly influencing the chromosomal topology, when confronted with sperm chromatin integrity components (DNA fragmentation or chromatin deprotamination).
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Chromosome (re)Positioning in spermatozoa of fathers and sons – carriers of reciprocal Chromosome translocation (RCT)
BMC Medical Genomics, 2019Co-Authors: Marta Olszewska, Alina T. Midro, Ewa Wiland, Nataliya Huleyuk, Monika Fraczek, Danuta Zastavna, Maciej KurpiszAbstract:Background Non-random Chromosome Positioning has been observed in the nuclei of several different tissue types, including human spermatozoa. The nuclear arrangement of Chromosomes can be altered in men with decreased semen parameters or increased DNA fragmentation and in males with chromosomal numerical or structural aberrations. An aim of this study was to determine whether and how the Positioning of nine Chromosome centromeres was (re)arranged in the spermatozoa of fathers and sons – carriers of the same reciprocal Chromosome translocation (RCT). Methods Fluorescence in situ hybridization (FISH) was applied to analyse the Positioning of sperm Chromosomes in a group of 13 carriers of 11 RCTs, including two familial RCT cases: t(4;5) and t(7;10), followed by analysis of eight control individuals. Additionally, sperm chromatin integrity was evaluated using TUNEL and Aniline Blue techniques. Results In the analysed familial RCT cases, rePositioning of the Chromosomes occurred in a similar way when compared to the data generated in healthy controls, even if some differences between father and son were further observed. These differences might have arisen from various statuses of sperm chromatin disintegration. Conclusions Nuclear topology appears as another aspect of epigenetic genomic regulation that may influence DNA functioning. We have re-documented that chromosomal Positioning is defined in control males and that a particular RCT is reflected in the individual pattern of chromosomal topology. The present study examining the collected RCT group, including two familial cases, additionally showed that chromosomal factors (karyotype and hyperhaploidy) have superior effects, strongly influencing the chromosomal topology, when confronted with sperm chromatin integrity components (DNA fragmentation or chromatin deprotamination).
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The effect of Robertsonian translocations on the intranuclear Positioning of NORs (nucleolar organizing regions) in human sperm cells
Nature Publishing Group, 2019Co-Authors: Ewa Wiland, Marta Olszewska, Nataliya Huleyuk, Vyacheslav B. Chernykh, Maciej KurpiszAbstract:Abstract Only a few studies have described sperm Chromosome intranuclear Positioning changes in men with reproductive failure and an incorrect somatic karyotype. We studied the influence of Robertsonian translocations on the acrocentric Chromosome Positioning in human sperm cells. The basis of the analysis was the localization of NORs (nucleolar organizing regions) in sperm nuclei from three Robertsonian translocation carriers, namely, rob(13;22), rob(13;15) and rob(13;14), with a known meiotic segregation pattern. All three carriers presented with a similar percentage of genetically normal sperm cells (i.e., approximately 40%). To visualize NORs, we performed 2D-FISH with directly labelled probes. We used the linear and radial topologies of the nucleus to analyse the NORs distribution. We found an affected Positioning of NORs in each case of the Robertsonian translocations. Moreover, the NORs tended to group, most often in two clusters. Both in Robertsonian carriers and control sperm cells, NORs mostly colocalized in the medial areas of the nuclei. In the case of the Roberstonian carriers, NORs were mostly concentrated in the peripheral part of the medial area, in contrast to control sperm cells in which the distribution was more dispersed towards the internal area
Tom Misteli - One of the best experts on this subject based on the ideXlab platform.
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an uncertainty principle in Chromosome Positioning
Trends in Cell Biology, 2003Co-Authors: Luis A Parada, Jeffrey Roix, Tom MisteliAbstract:Chromosomes are non-randomly positioned in the mammalian interphase nucleus. It is not known how patterns of Chromosome positions are established or to what degree spatial arrangements of Chromosomes change during the cell cycle, especially during mitosis. Two reports have applied in vivo microscopy to track Chromosomes in space and time. The results highlight the inherently imperfect and probabilistic nature of Chromosome Positioning in the cell nucleus.
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conservation of relative Chromosome Positioning in normal and cancer cells
Current Biology, 2002Co-Authors: Luis A Parada, Philip G Mcqueen, Peter J Munson, Tom MisteliAbstract:Abstract Chromosomes exist in the interphase nucleus as individual Chromosome territories. It is unclear to what extent Chromosome territories occupy particular positions with respect to each other and how structural rearrangements, such as translocations, affect Chromosome organization within the cell nucleus. Here we analyze the relative interphase Positioning of Chromosomes in mouse lymphoma cells compared to normal splenocytes. We show that in a lymphoma cell line derived from an ATM −/− mouse, two translocated Chromosomes are preferentially positioned in close proximity to each other. The relative position of the Chromosomes involved in these translocations is conserved in normal splenocytes. Relative Positioning of Chromosomes in normal splenocytes is not due to their random distribution in the interphase nucleus and persists during mitosis. These observations demonstrate that the relative arrangement of Chromosomes in the interphase nucleus can be conserved between normal and cancer cells and our data support the notion that physical proximity facilitates rearrangements between Chromosomes.
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Chromosome Positioning in the interphase nucleus
Trends in Cell Biology, 2002Co-Authors: Luis A Parada, Tom MisteliAbstract:Chromosomes occupy distinct territories in the interphase cell nucleus. These Chromosome territories are non-randomly arranged within the nuclear space. We are only just uncovering how Chromosome territories are organized, what determines their position and how their spatial organization affects the expression of genes and genomes. Here, we discuss emerging models of non-random nuclear Chromosome organization and consider the functional implications of Chromosome Positioning for gene expression and genome stability.
Ishita S Mehta - One of the best experts on this subject based on the ideXlab platform.
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rapid Chromosome territory relocation by nuclear motor activity in response to serum removal in primary human fibroblasts
Genome Biology, 2010Co-Authors: Ishita S Mehta, Manelle Amira, Amanda J Harvey, Joanna M BridgerAbstract:Background Radial Chromosome Positioning in interphase nuclei is nonrandom and can alter according to developmental, differentiation, proliferation, or disease status. However, it is not yet clear when and how Chromosome rePositioning is elicited.
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rapid Chromosome territory relocation by nuclear motor activity in response to serum removal in primary human fibroblasts
Genome Biology, 2010Co-Authors: Ishita S Mehta, Manelle Amira, Amanda J Harvey, Joanna M BridgerAbstract:Radial Chromosome Positioning in interphase nuclei is nonrandom and can alter according to developmental, differentiation, proliferation, or disease status. However, it is not yet clear when and how Chromosome rePositioning is elicited. By investigating the Positioning of all human Chromosomes in primary fibroblasts that have left the proliferative cell cycle, we have demonstrated that in cells made quiescent by reversible growth arrest, Chromosome Positioning is altered considerably. We found that with the removal of serum from the culture medium, Chromosome rePositioning took less than 15 minutes, required energy and was inhibited by drugs affecting the polymerization of myosin and actin. We also observed that when cells became quiescent, the nuclear distribution of nuclear myosin 1β was dramatically different from that in proliferating cells. If we suppressed the expression of nuclear myosin 1β by using RNA-interference procedures, the movement of Chromosomes after 15 minutes in low serum was inhibited. When high serum was restored to the serum-starved cultures, Chromosome rePositioning was evident only after 24 to 36 hours, and this coincided with a return to a proliferating distribution of nuclear myosin 1β. These findings demonstrate that genome organization in interphase nuclei is altered considerably when cells leave the proliferative cell cycle and that rePositioning of Chromosomes relies on efficient functioning of an active nuclear motor complex that contains nuclear myosin 1β.
Danuta Zastavna - One of the best experts on this subject based on the ideXlab platform.
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Chromosome re Positioning in spermatozoa of fathers and sons carriers of reciprocal Chromosome translocation rct
BMC Medical Genomics, 2019Co-Authors: Marta Olszewska, Alina T. Midro, Ewa Wiland, Nataliya Huleyuk, Monika Fraczek, Danuta Zastavna, Maciej KurpiszAbstract:Non-random Chromosome Positioning has been observed in the nuclei of several different tissue types, including human spermatozoa. The nuclear arrangement of Chromosomes can be altered in men with decreased semen parameters or increased DNA fragmentation and in males with chromosomal numerical or structural aberrations. An aim of this study was to determine whether and how the Positioning of nine Chromosome centromeres was (re)arranged in the spermatozoa of fathers and sons – carriers of the same reciprocal Chromosome translocation (RCT). Fluorescence in situ hybridization (FISH) was applied to analyse the Positioning of sperm Chromosomes in a group of 13 carriers of 11 RCTs, including two familial RCT cases: t(4;5) and t(7;10), followed by analysis of eight control individuals. Additionally, sperm chromatin integrity was evaluated using TUNEL and Aniline Blue techniques. In the analysed familial RCT cases, rePositioning of the Chromosomes occurred in a similar way when compared to the data generated in healthy controls, even if some differences between father and son were further observed. These differences might have arisen from various statuses of sperm chromatin disintegration. Nuclear topology appears as another aspect of epigenetic genomic regulation that may influence DNA functioning. We have re-documented that chromosomal Positioning is defined in control males and that a particular RCT is reflected in the individual pattern of chromosomal topology. The present study examining the collected RCT group, including two familial cases, additionally showed that chromosomal factors (karyotype and hyperhaploidy) have superior effects, strongly influencing the chromosomal topology, when confronted with sperm chromatin integrity components (DNA fragmentation or chromatin deprotamination).
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Chromosome (re)Positioning in spermatozoa of fathers and sons – carriers of reciprocal Chromosome translocation (RCT)
BMC Medical Genomics, 2019Co-Authors: Marta Olszewska, Alina T. Midro, Ewa Wiland, Nataliya Huleyuk, Monika Fraczek, Danuta Zastavna, Maciej KurpiszAbstract:Background Non-random Chromosome Positioning has been observed in the nuclei of several different tissue types, including human spermatozoa. The nuclear arrangement of Chromosomes can be altered in men with decreased semen parameters or increased DNA fragmentation and in males with chromosomal numerical or structural aberrations. An aim of this study was to determine whether and how the Positioning of nine Chromosome centromeres was (re)arranged in the spermatozoa of fathers and sons – carriers of the same reciprocal Chromosome translocation (RCT). Methods Fluorescence in situ hybridization (FISH) was applied to analyse the Positioning of sperm Chromosomes in a group of 13 carriers of 11 RCTs, including two familial RCT cases: t(4;5) and t(7;10), followed by analysis of eight control individuals. Additionally, sperm chromatin integrity was evaluated using TUNEL and Aniline Blue techniques. Results In the analysed familial RCT cases, rePositioning of the Chromosomes occurred in a similar way when compared to the data generated in healthy controls, even if some differences between father and son were further observed. These differences might have arisen from various statuses of sperm chromatin disintegration. Conclusions Nuclear topology appears as another aspect of epigenetic genomic regulation that may influence DNA functioning. We have re-documented that chromosomal Positioning is defined in control males and that a particular RCT is reflected in the individual pattern of chromosomal topology. The present study examining the collected RCT group, including two familial cases, additionally showed that chromosomal factors (karyotype and hyperhaploidy) have superior effects, strongly influencing the chromosomal topology, when confronted with sperm chromatin integrity components (DNA fragmentation or chromatin deprotamination).