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Robin Lovellbadge - One of the best experts on this subject based on the ideXlab platform.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge, Sergio Ottolenghi
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

R Catena - One of the best experts on this subject based on the ideXlab platform.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge, Sergio Ottolenghi
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

M V Zappone - One of the best experts on this subject based on the ideXlab platform.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge, Sergio Ottolenghi
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.

Leslie L. Heckert - One of the best experts on this subject based on the ideXlab platform.

  • DOI 10.1095/biolreprod.108.072314 Distinct Transcriptional Mechanisms Direct Expression of the Rat Dmrt1 Promoter
    2016
    Co-Authors: In Sertoli Cells, Germ Cells, Transgenic Mice, Ning Lei, Tatiana Karpova, Kaori I. Hornbaker, Daren A. Rice, Leslie L. Heckert
    Abstract:

    DMRT1 is a transcription factor expressed only in Sertoli cells and undifferentiated spermatogonia of the postnatal testis, where it is required for proper cellular differentiation and fertility. To elucidate the transcriptional regulatory regions that provide DMRT1’s cell-specific Expression, transgenic mice containing a LacZ reporter gene driven by variable amounts of rat Dmrt1 50 flanking sequence, 9 kb and smaller, were evaluated. Examination of transgene Expression by RT-PCR indicated that multiple promoter regions Direct Dmrt1 to the testis and that sequences upstream of 2.8 kb are needed for both Sertoli cell Expression and limiting transcriptional influence imposed by surrounding chromatin. Thus, whereas many of the transgenes were expressed in the testis, the ones with smaller promoters were significantly more prone to Expression at ectopic sites or to complete silencing. Transgene Expression in Sertoli cells and germ cells was assessed by immunohistochemistry and RT-PCR following busulfan treat-ment to remove germ cells. Both evaluations indicated Expression of the 9- and 3.2-kb promoters in Sertoli cells and germ cells, whereas activity of smaller promoters was largely restricted to germ cells. In all, the present study provides in vivo evidence that distinct promoter sequences participate in Dmrt1 regulation in somatic cells and germ cells, with the3.2 kb/2.8 kb region Directing Expression in Sertoli cells and downstream sequences (1.3 kb) Directing it in germ cells. Further exploration of the mechanisms restricting Dmrt1 Expression to the testis revealed that FOXL2, a transcription factor required for differentiation of the ovary, repressed Dmrt1 promoter through the 3.2 kb/2.8 kb regulatory region, offering a potential mechanism for Dmrt1 transcrip-tional silencing in granulosa cells. Dmrt1, FOXL2, testis, testis development, transcription, transcription regulation, transgenic mice, transgenic mice spermatogenesi

  • distinct transcriptional mechanisms Direct Expression of the rat dmrt1 promoter in sertoli cells and germ cells of transgenic mice
    Biology of Reproduction, 2009
    Co-Authors: Ning Lei, Kaori I. Hornbaker, Daren A. Rice, Tatiana S Karpova, Leslie L. Heckert
    Abstract:

    DMRT1 is a transcription factor expressed only in Sertoli cells and undifferentiated spermatogonia of the postnatal testis, where it is required for proper cellular differentiation and fertility. To elucidate the transcriptional regulatory regions that provide DMRT1's cell-specific Expression, transgenic mice containing a LacZ reporter gene driven by variable amounts of rat Dmrt1 5′ flanking sequence, 9 kb and smaller, were evaluated. Examination of transgene Expression by RT-PCR indicated that multiple promoter regions Direct Dmrt1 to the testis and that sequences upstream of 2.8 kb are needed for both Sertoli cell Expression and limiting transcriptional influence imposed by surrounding chromatin. Thus, whereas many of the transgenes were expressed in the testis, the ones with smaller promoters were significantly more prone to Expression at ectopic sites or to complete silencing. Transgene Expression in Sertoli cells and germ cells was assessed by immunohistochemistry and RT-PCR following busulfan treatment to remove germ cells. Both evaluations indicated Expression of the 9- and 3.2-kb promoters in Sertoli cells and germ cells, whereas activity of smaller promoters was largely restricted to germ cells. In all, the present study provides in vivo evidence that distinct promoter sequences participate in Dmrt1 regulation in somatic cells and germ cells, with the −3.2 kb/−2.8 kb region Directing Expression in Sertoli cells and downstream sequences (≤1.3 kb) Directing it in germ cells. Further exploration of the mechanisms restricting Dmrt1 Expression to the testis revealed that FOXL2, a transcription factor required for differentiation of the ovary, repressed Dmrt1 promoter through the −3.2 kb/−2.8 kb regulatory region, offering a potential mechanism for Dmrt1 transcriptional silencing in granulosa cells.

Sergio Ottolenghi - One of the best experts on this subject based on the ideXlab platform.

  • sox2 regulatory sequences Direct Expression of a beta geo transgene to telencephalic neural stem cells and precursors of the mouse embryo revealing regionalization of gene Expression in cns stem cells
    Development, 2000
    Co-Authors: M V Zappone, Rossella Galli, R Catena, N Meani, S De Biasi, E Mattei, C Tiveron, Angelo L Vescovi, Robin Lovellbadge, Sergio Ottolenghi
    Abstract:

    Sox2 is one of the earliest known transcription factors expressed in the developing neural tube. Although it is expressed throughout the early neuroepithelium, we show that its later Expression must depend on the activity of more than one regionally restricted enhancer element. Thus, by using transgenic assays and by homologous recombination-mediated deletion, we identify a region upstream of Sox2 (−5.7 to −3.3 kb) which can not only drive Expression of a (beta)-geo transgene to the developing dorsal telencephalon, but which is required to do so in the context of the endogenous gene. The critical enhancer can be further delimited to an 800 bp fragment of DNA surrounding a nuclease hypersensitive site within this region, as this is sufficient to confer telencephalic Expression to a 3.3 kb fragment including the Sox2 promoter, which is otherwise inactive in the CNS. Expression of the 5.7 kb Sox2(beta)-geo transgene localizes to the neural plate and later to the telencephalic ventricular zone. We show, by in vitro clonogenic assays, that transgene-expressing (and thus G418-resistant) ventricular zone cells include cells displaying functional properties of stem cells, i.e. self-renewal and multipotentiality. We further show that the majority of telencephalic stem cells express the transgene, and this Expression is largely maintained over two months in culture (more than 40 cell divisions) in the absence of G418 selective pressure. In contrast, stem cells grown in parallel from the spinal cord never express the transgene, and die in G418. Expression of endogenous telencephalic genes was similarly observed in long-term cultures derived from the dorsal telencephalon, but not in spinal cord-derived cultures. Thus, neural stem cells of the midgestation embryo are endowed with region-specific gene Expression (at least with respect to some networks of transcription factors, such as that driving telencephalic Expression of the Sox2 transgene), which can be inherited through multiple divisions outside the embryonic environment.