Project description:Whole genome expression profiling in the presence and absence of annexin A2 [shRNA] identified fundamentally altered transcriptional programming that changes the radioresponsive transcriptome. Bioinformatics predicted that silencing AnxA2 may enhance cell death responses to stress in association with reduced activation of pro-survival signals such as nuclear factor kappa B. This prediction was validated by demonstrating a significant increase in sensitivity toward tumor necrosis factor alpha induced cell death in annexin A2 silenced cells, relative to vector controls, associated with reduced nuclear translocation of RelA (p65) following tumor necrosis factor alpha treatment. Murine progenitor cells, JB6 cell line, were stably transformed with Annexin A2 shRNA or vector only control and then treated with ionizing radiation at two doses, 10cGy and 100cGy. Samples were collected at 2hr, 6hr and 24hr for RNA isolation. Two untreated time points were collected also: 2hr and 24hr.
Project description:Whole genome expression profiling in the presence and absence of annexin A2 [shRNA] identified fundamentally altered transcriptional programming that changes the radioresponsive transcriptome. Bioinformatics predicted that silencing AnxA2 may enhance cell death responses to stress in association with reduced activation of pro-survival signals such as nuclear factor kappa B. This prediction was validated by demonstrating a significant increase in sensitivity toward tumor necrosis factor alpha induced cell death in annexin A2 silenced cells, relative to vector controls, associated with reduced nuclear translocation of RelA (p65) following tumor necrosis factor alpha treatment.
Project description:We have previously established two sibling glioma subclones, J3T-1 and J3T-2, showing distinct invasive and angiogenic phenotypes. J3T-1, expressing high annexin A2, demonstrates robust angiogenesis and tumor invasion around neovasculature. J3T-2, expressing low annexin A2, demonstrates diffuse invasion along white matter tracts. Knockdown of annexin A2 in J3T-1 (J3T-1shA) resulted in diffuse invasion pattern, and overexpression of annexin A2 in J3T-2 (J3T-2A) showed prominent angiogenesis. We used microarrays to identify genes which promote the phenotypic transition regulated by annexin A2.
Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes.
Project description:Cellular binary fate decisions require the progeny to silence genes associated with the alternative fate. The major subsets of alpha:beta T cells have been extensively studied as a model system for fate decisions. While the transcription factor RUNX3 is required for the initiation of Cd4 silencing in CD8 T cell progenitors, it is not required to maintain the silencing of Cd4 and other helper T lineage genes. The other runt domain containing protein, RUNX1, silences Cd4 in an earlier T cell progenitor, but this silencing is reversed whereas the gene silencing after RUNX3 expression is not reverse. Therefore, we hypothesized that RUNX3 and not RUNX1 recruits other factors that maintains the silencing of helper T lineage genes in CD8 T cells. To this end, we performed a proteomics screen of RUNX1 and RUNX3 to determine candidate silencing factors.
Project description:A mass-spec of proteins found bound to Annexin A2 following a immunoprecipitation of Annexin A2 from cell lysate of MDAMB231 cells plated 1) on plastic or 2) on collagen-1
