Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. Liver NK 1.1+CD49+, liver NK 1.1+CD49-, spleen NK 1.1+ CD49- populations of NK cells were sorted with FACS pooling cells from individual mice to end up with ~100k cells for each samples. mRNA was derived from lysates using Invitrogen oligo-dT beads
Project description:TCF-1 is an HMG family transcription factor which is known to be critical for T cell development. We discovered that it has a unique role in suppressing malignant transformation of developing thymocytes at early stages. We identified ID2 and LEF-1 as key TCF-1 target genens in tumor suppression. We used microarrays to detect gene expression changes in WT and TCF-1 deficient DN3 thymocytes as well as T cell lymphoma cells developed in TCF-1 KO mice. DN3 thymocytes were directly sorted from WT or TCF-1 KO mice. T cell lymphoma blast cells were also sorted from TCF-1 KO mice that developed the disease. RNA was extracted and hybridized to GeneChip Mouse GENE 1.0 ST arrays (Affymetrix).
Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. Liver DX5-CD49+, liver DX5+CD49-, spleen DX5+ CD49- populations of NK cells were sorted with FACS pooling cells from individual mice to end up with ~100k cells for each samples. mRNA was derived from lysates using Invitrogen oligo-dT beads
Project description:In development, pioneer transcription factors access silent chromatin to reveal lineage-specific gene programs. The structured DNA-binding domains of pioneer factors have been well characterized, but whether and how low-complexity intrinsically disordered regions (IDRs) affect chromatin and control cell fate is unclear. Here, we report deletion of an IDR of the pioneer factor TCF-1, termed “L1”, leads to an early developmental block in T cells. The few T cells that develop from progenitors expressing TCF-1 lacking L1 exhibit lineage infidelity distinct from the lineage diversion of TCF-1 deficient cells. Mechanistically, L1 is required for activation of T cell genes and de-repression of GATA2 driven genes, normally reserved to the mast cell and dendritic cell lineages. Underlying this lineage diversion, L1 mediates binding of TCF-1 to its earliest target genes which are subject to repression as T cells develop. These data suggest TCF-1’s intrinsically disordered N-terminus maintains T cell lineage fidelity.
Project description:TCF-1 is an HMG family transcription factor which is known to be critical for T cell development. We discovered that it has a unique role in suppressing malignant transformation of developing thymocytes at early stages. We identified ID2 and LEF-1 as key TCF-1 target genens in tumor suppression. We used microarrays to detect gene expression changes in WT and TCF-1 deficient DN3 thymocytes as well as T cell lymphoma cells developed in TCF-1 KO mice.
Project description:Both TCF-1 and its coactivator β-catenin are known to be required for supporting normal double positive (DP) thymocyte survival through upregulating Bcl-xL. However, the downstream factors mediating this effect remained unknown. We used microarray to compare the global expression difference among WT, TCF-1-deficient, and β-catenin transgenic thymocytes to search for the genes that are down-regulated and up-regulated in TCF-1-deficient and β-catenin transgenic thymocytes, respectively. We focus on the genes that are significantly down-regulated and up-regulated in TCF-1-deficient and β-catenin transgenic thymocytes, respectively, to select for those genes that are potential target genes of β-catenin/TCF-1 pathway. And then those genes are subject to IPA pathway analysis searching for genes that are involved in thymocyte development and cell death.
Project description:We sought to identify the carcinogenic mechanisms involved in RKO cell line with no evidence of activated β-catenin/TCF regulated transcription, by comparison its gene expression profile to that of group of colorectal cancer cell lines selected to be mismatch repair deficient similar to RKO and having activate Wnt signaling.