Project description:To investigate gene targets of the E-proteins HEB and E2A during the CD4+CD8+ double positive (DP) stage of T cell development. We examined E-protein function by simultaneous removal of both HEB (Tcf12) and E2A (Tcfe2a) genes at the DP stage. This was done by crossing mice containing HEB floxed and E2A floxed alleles to a CD4Cre background (Tcf12f/fTcfe2af/fCD4Cre mice). Microarray analysis was used to compare gene expression in HEB and E2A double deficient DP thymocytes (Cre+) to Cre- control DP thymocytes. Keywords: genetic modification
Project description:We wanted to test the role of mammalian E proteins E2A and HEB in the development of T cells. Using a conditional deletion system in which these proteins are deleted at the DP stage of T cell development, we compared DP thymocytes deficient for E2A, HEB or both to wild-type thymocytes
Project description:T lymphocyte acute lymphoblastic leukemia (T-ALL) is frequently associated with increased expression of the E protein transcription factor inhibitors TAL1 and LYL1. In mouse models, ectopic expression of Tal1 or Lyl1 in T cell progenitors, or inactivation of E2a, is sufficient to predispose mice to develop T-ALL. How E2a suppresses thymocyte transformation is currently unknown. Here, we show that early deletion of E2a, prior to the DN3 stage, was required for robust leukemogenesis and was associated with alterations in thymus cellularity, T cell differentiation, and gene expression in immature CD4+CD8+ thymocytes. Introduction of wild-type thymocytes into mice with early deletion of E2a prevented leukemogenesis, or delayed disease onset, and impacted the expression of multiple genes associated with transformation and genome instability. Our data indicate that E2a suppresses leukemogenesis by promoting T cell development and enforcing inter-thymocyte competition, a mechanism that is emerging as a safeguard against thymocyte transformation. These studies have implications for understanding how multiple essential regulators of T cell development suppress T-ALL and support the hypothesis that thymus cellularity is a determinant of leukemogenesis
Project description:We report the changes in Tcrb interactome upon transitioning from DN to DP stage of thymocyte development Examination of the interactomes of Eb and Trbv5 viewpoints in RAG-deficient DN and DP thymocytes
Project description:NSrp70 deficiency (NSRP1f/fCD4Cre) profoundly perturbed the late development of DP thymocytes, leading to a significant reduction of single positive (SP) cells in the thymus and peripheral lymphoid tissues. To gain further insight how NSrp70 controls thymocyte development from DP stage, we performed RNA-seq analysis after sorting DP thymocytes from WT and Nsrp1 cKO mice.
Project description:NSrp70 deficiency (NSRP1f/fCD4Cre) profoundly perturbed the late development of DP thymocytes, leading to a significant reduction of single positive (SP) cells in the thymus and peripheral lymphoid tissues. To gain further insight into how NSrp70 controls thymocyte development from CD69+ DP stage, we performed RNA-seq analysis after sorting CD69+ DP thymocytes from WT and Nsrp1 cKO mice.
Project description:Analysis of ESET deficient thymocytes at gene expression level. Each thymocyte developmental stage (preselected DP, postselected DP and CD4SP) was analysed.
Project description:CD4+ and CD8+ double-positive (DP) thymocytes are at a critical stage during the T cell development in thymus. DP cells rearrange the T cell receptor gene Tcra to generate T cell receptors with TCR. Then DP cells differentiate into CD4 or CD8 single-positive (SP) thymocytes, Regulatory T cells, or invariant nature kill T cells (iNKT) according to the TCR signal. Chromatin organizer SATB1 is highly expressed in DP cells and plays an essential role in regulating Tcra rearrangement and differentiation of DP cells. Here we explored the mechanism of SATB1 orchestrating gene expression in DP cells. Single-cell RNA sequencing assay of SATB1-deficient thymocytes showed that the cell identity of DP thymocytes was changed, and the genes specifically highly expressed in DP cells were down-regulated. ChIP-seq and ATAC-seq data showed the similar tendency. The super-enhancers regulate the expressions of the DP-specific genes, and the SATB1 deficiency reduced the super-enhancer activity. Hi-C data showed that interactions in super-enhancers and between super-enhancers and promoters decreased in SATB1 deficient thymocytes. We further explored the regulation mechanism of two SATB1-regulating genes, ETS2 and Bcl6, in DP cells and found that the knockout of the super-enhancers of these two genes impaired the development of DP cells. Our research reveals that SATB1 globally regulates super-enhancers of DP cells and promotes the establishment of DP cell identity, which helps understand the role of SATB1 in thymocyte development.
Project description:The lymphoid branch of the immune defense is composed of innate and adaptive immune cells. Using multiple genetic strategies we demonstrate that in the thymus E2A and HEB act in synergy to establish T cell identity and to suppress the aberrant development of innate lymphoid cells that include ILC2 and LTi-like cells. We found that E2A and HEB induce T cell fate by activating the expression of an ensemble of genes encoding for proteins associated with Notch- and pre-TCR signaling and to promote TCRβ antigen receptor assembly. We show that E2A and HEB act in early T progenitors (ETPs) to establish and maintain a T-lineage specific enhancer repertoire, including regulatory elements associated with the Notch1/3 and Rag1/2 gene loci. Based on these and previous observations we propose that the E-Id protein axis specifies innate versus adaptive lymphoid cell fate.
