GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 186, No. 1_Supplement ( 2011-04-01), p. 62.1-62.1
    Abstract: V(D)J recombination provides the foundation for adaptive immunity. This complicated process involves the cleavage of specific recombination signal sequences (RSS) by the recombination activating gene products, RAG1 and RAG2, followed by repair of the DNA double-stranded breaks (DSBs) by the non-homologous end joining (NHEJ) factors, including DNA dependent protein kinase (DNA-PK), Artemis, Ku86, Ku70, DNA ligase IV, XRCC4, XLF, and HMGB1. Currently, it is not clear how these factors are organized inside of the nuclei for recombination. Accumulating studies indicate that the multiple-component DNA replication and RNA transcription machineries are organized as large complexes on the nuclear matrix (NM). Here we show that RAG1, RAG2, and many NHEJ factors are associated with the NM, where they appear to form large complexes and are distributed closely at discrete foci. Ongoing RSS cleavage mainly occurs on the NM in developing B, T lineage cells and HEK293 cells with an artificial recombination system; Purified NMs containing RAG and NHEJ proteins possess the entire enzymatically active recombination system to cleave RSS substrates and generate coding joints in vitro. These results support a novel model that the V(D)J recombination machinery is organized as large complexes anchored on the NM to conduct recombination.
    Type of Medium: Online Resource
    ISSN: 0022-1767 , 1550-6606
    RVK:
    RVK:
    Language: English
    Publisher: The American Association of Immunologists
    Publication Date: 2011
    detail.hit.zdb_id: 1475085-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 190, No. 11 ( 2013-06-01), p. 5559-5566
    Abstract: VH replacement provides a unique RAG-mediated recombination mechanism to edit nonfunctional IgH genes or IgH genes encoding self-reactive BCRs and contributes to the diversification of Ab repertoire in the mouse and human. Currently, it is not clear how VH replacement is regulated during early B lineage cell development. In this article, we show that cross-linking BCRs induces VH replacement in human EU12 μHC+ cells and in the newly emigrated immature B cells purified from peripheral blood of healthy donors or tonsillar samples. BCR signaling–induced VH replacement is dependent on the activation of Syk and Src kinases but is inhibited by CD19 costimulation, presumably through activation of the PI3K pathway. These results show that VH replacement is regulated by BCR-mediated signaling in human immature B cells, which can be modulated by physiological and pharmacological treatments.
    Type of Medium: Online Resource
    ISSN: 0022-1767 , 1550-6606
    RVK:
    RVK:
    Language: English
    Publisher: The American Association of Immunologists
    Publication Date: 2013
    detail.hit.zdb_id: 1475085-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: BioMed Research International, Hindawi Limited, Vol. 2013 ( 2013), p. 1-9
    Abstract: It has been recognized for a long time that engagement of B cell antigen receptors (BCRs) on immature B cells or mature B cells leads to completely opposite cell fate decisions. The underlying mechanism remains unclear. Here, we show that crosslinking of BCRs on human EU12 μ HC + immature B cells resulted in complete internalization of cell surface BCRs. After loss of cell surface BCRs, restimulation of EU12 μ HC + cells showed impaired Ca 2+ flux, delayed SYK phosphorylation, and decreased CD19 and FOXO1 phosphorylation, which differ from those in mature Daudi or Ramos B cells with partial internalization of BCRs. In contrast, sustained phosphorylation and reactivation of ERK upon restimulation were observed in the EU12 μ HC + cells after BCR internalization. Taken together, these results show that complete internalization of cell surface BCRs in EU12 μ HC + cells specifically alters the downstream signaling events, which may favor receptor editing versus cell activation.
    Type of Medium: Online Resource
    ISSN: 2314-6133 , 2314-6141
    Language: English
    Publisher: Hindawi Limited
    Publication Date: 2013
    detail.hit.zdb_id: 2698540-8
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    The American Association of Immunologists ; 2011
    In:  The Journal of Immunology Vol. 186, No. 1_Supplement ( 2011-04-01), p. 153.14-153.14
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 186, No. 1_Supplement ( 2011-04-01), p. 153.14-153.14
    Abstract: Accumulating studies indicate that the nuclear matrix provides a dynamic structural support for various biological reactions inside of nuclei such as DNA replication, RNA transcription, and RNA splicing. Pax5 is an important regulator for B lineage cell development, which controls the B lineage specific gene expression program involving hundreds of positive and negative target genes. Here, we show that majority of the endogenous Pax5 proteins in human and murine B lineage cells are associated with the nuclear matrix, where they occupy the centers for transcription on the nuclear matrix as indicated by co-localization with the RNA polymerase II or the TATA box binding protein (TBP). Detailed analyses identified that two different domains of Pax5 are required for its association with the nuclear matrix. Interestingly, lysine 67, 87, and 89 residues within the PRD domain of Pax5 are essential for its association with the nuclear matrix. Microarray analysis showed that mutation of these lysine residues compromise Pax5 mediated activation and repression of hundreds target genes. Furthermore, chromatin immunoprecipitation (ChIP) and nuclear matrix foot printing assays indicated that Pax5 is responsible for recruitment of Cd19 loci to the nuclear matrix bound RNA polymerase complex. These results demonstrate that association with the nuclear matrix is essential for Pax5 to control the B lineage specific gene expression program.
    Type of Medium: Online Resource
    ISSN: 0022-1767 , 1550-6606
    RVK:
    RVK:
    Language: English
    Publisher: The American Association of Immunologists
    Publication Date: 2011
    detail.hit.zdb_id: 1475085-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    The American Association of Immunologists ; 2010
    In:  The Journal of Immunology Vol. 184, No. 1_Supplement ( 2010-04-01), p. 88.3-88.3
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 184, No. 1_Supplement ( 2010-04-01), p. 88.3-88.3
    Abstract: Somatic recombination of immunoglobulin or T cell antigen receptor genes occurs through recombination activating gene product (RAG)-mediated cleavage at recombination signal sequences (RSS) and subsequently, the broken DNA ends are repaired by non-homologue end joining (NHEJ) enzymes. Here, we show that RAG1, RAG2, and many NHEJ factors in B lineage cells are associated with the nuclear matrix. The core RAG1 and RAG2 proteins have their own nuclear matrix targeting regions. RAG-mediated double stranded DNA breaks at the Jκ4 RSS can be readily detected in the nuclear matrix fraction in Gleevec treated Abelson transformed murine B cells or mouse bone marrow cells, indicating that the recombination reaction is ongoing on the nuclear matrix. In the HEK 293 cell-based recombination system, artificial recombination substrates are recruited to the nuclear matrix for recombination. Moreover, nuclear matrix proteins purified from 293 cells expressing the core RAG proteins or human B lineage cells expressing endogenous RAG proteins support cleavage of RSS substrates in vitro. Based on these results, we propose that the V(D)J recombination machinery is associated with the nuclear matrix.
    Type of Medium: Online Resource
    ISSN: 0022-1767 , 1550-6606
    RVK:
    RVK:
    Language: English
    Publisher: The American Association of Immunologists
    Publication Date: 2010
    detail.hit.zdb_id: 1475085-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...