Project description:ZBTB20 is an adjuvant-specific factor for long-term antibody responses. This factor is critical for maintaining long-lived plasma cells in alum-adjuvanted antibody responses but is dispensable for TLR ligand-adjuvanted responses. To identify the functions of ZBTB20 in long-lived plasma cells, we performed microarray analysis on Zbtb20-sufficient and Zbtb20-deficient polyclonal bone marrow plasma cells under the assumption that ZBTB20 regulates relevant targets in all long-lived plasma cells, irrespective of their mode of formation. Chimeras were generated using Zbtb20-sufficient (WT) or Zbtb20-deficient (TRAP) E14.5 fetal livers. 3-4 months after reconstitution, donor bone marrow B220low/-CD138+ cells (4 replicates per genotype) were purified via FACS for microarray. In total, 8 samples, 4 for each genotype, were included in this study.
Project description:ZBTB20 is an adjuvant-specific factor for long-term antibody responses. This factor is critical for maintaining long-lived plasma cells in alum-adjuvanted antibody responses but is dispensable for TLR ligand-adjuvanted responses. To identify the functions of ZBTB20 in long-lived plasma cells, we performed microarray analysis on Zbtb20-sufficient and Zbtb20-deficient polyclonal bone marrow plasma cells under the assumption that ZBTB20 regulates relevant targets in all long-lived plasma cells, irrespective of their mode of formation.
Project description:B cells provide humoral immunity by differentiating into antibody-secreting plasma cells, a process that requires cell division and is linked to DNA hypomethylation and gene regulation. Conversely, accumulation of DNA methylation in B cell differentiation is less apparent. To determine the role of de novo DNA methylation in B cell differentiation, the de novo DNA methyltransferases, Dnmt3a and Dnmt3b, were deleted in B cells resulting in phenotypically normal B cell development in the bone marrow, spleen and lymph nodes. However, upon immunologic challenge, mice deficient for Dnmt3a and Dnmt3b (Dnmt3-deficient) accumulated more antigen-specific B cells and bone marrow chimeras showed this was cell-autonomous. Additionally, a five-fold increase in splenic and bone marrow plasma cells was observed. Molecular analysis revealed that Dnmt3-deficient bone marrow plasma cells failed to repress gene expression to the same level as their Dnmt3ab-sufficient counterparts. This was coupled with a failure of Dnmt3-deficient germinal center B cells and plasma cells to gain and/or maintain DNA methylation at several thousand loci that were clustered in enhancers of genes that function in B cell activation and homing. Analysis of chromatin accessibility showed Dnmt3-deficient plasma cells had increased accessibility at several genes involved in hematopoiesis and B cell differentiation. These data show that de novo DNA methylation limits B cell activation, proliferation and differentiation, and support a model whereby DNA methylation represses the aberrant transcription of genes silenced in B cell differentiation to maintain plasma cell homeostasis.
Project description:B cells provide humoral immunity by differentiating into antibody-secreting plasma cells, a process that requires cell division and is linked to DNA hypomethylation and gene regulation. Conversely, accumulation of DNA methylation in B cell differentiation is less apparent. To determine the role of de novo DNA methylation in B cell differentiation, the de novo DNA methyltransferases, Dnmt3a and Dnmt3b, were deleted in B cells resulting in phenotypically normal B cell development in the bone marrow, spleen and lymph nodes. However, upon immunologic challenge, mice deficient for Dnmt3a and Dnmt3b (Dnmt3-deficient) accumulated more antigen-specific B cells and bone marrow chimeras showed this was cell-autonomous. Additionally, a five-fold increase in splenic and bone marrow plasma cells was observed. Molecular analysis revealed that Dnmt3-deficient bone marrow plasma cells failed to repress gene expression to the same level as their Dnmt3ab-sufficient counterparts. This was coupled with a failure of Dnmt3-deficient germinal center B cells and plasma cells to gain and/or maintain DNA methylation at several thousand loci that were clustered in enhancers of genes that function in B cell activation and homing. Analysis of chromatin accessibility showed Dnmt3-deficient plasma cells had increased accessibility at several genes involved in hematopoiesis and B cell differentiation. These data show that de novo DNA methylation limits B cell activation, proliferation and differentiation, and support a model whereby DNA methylation represses the aberrant transcription of genes silenced in B cell differentiation to maintain plasma cell homeostasis.
Project description:B cells provide humoral immunity by differentiating into antibody-secreting plasma cells, a process that requires cell division and is linked to DNA hypomethylation and gene regulation. Conversely, accumulation of DNA methylation in B cell differentiation is less apparent. To determine the role of de novo DNA methylation in B cell differentiation, the de novo DNA methyltransferases, Dnmt3a and Dnmt3b, were deleted in B cells resulting in phenotypically normal B cell development in the bone marrow, spleen and lymph nodes. However, upon immunologic challenge, mice deficient for Dnmt3a and Dnmt3b (Dnmt3-deficient) accumulated more antigen-specific B cells and bone marrow chimeras showed this was cell-autonomous. Additionally, a five-fold increase in splenic and bone marrow plasma cells was observed. Molecular analysis revealed that Dnmt3-deficient bone marrow plasma cells failed to repress gene expression to the same level as their Dnmt3ab-sufficient counterparts. This was coupled with a failure of Dnmt3-deficient germinal center B cells and plasma cells to gain and/or maintain DNA methylation at several thousand loci that were clustered in enhancers of genes that function in B cell activation and homing. Analysis of chromatin accessibility showed Dnmt3-deficient plasma cells had increased accessibility at several genes involved in hematopoiesis and B cell differentiation. These data show that de novo DNA methylation limits B cell activation, proliferation and differentiation, and support a model whereby DNA methylation represses the aberrant transcription of genes silenced in B cell differentiation to maintain plasma cell homeostasis.
Project description:The transcriptional repressor Zbtb20 is essential for specification of hippocampal CA1 pyramidal neurons. Moreover, ectopic expression of Zbtb20 is sufficient to transform subicular and retrosplenial areas of D6/Zbtb20S mice to CA1. We used microarrays to identify genes that are repressed by Zbtb20 in developing CA1 pyramidal neurons in the CA1-transformed cortex of D6/Zbtb20S mice.