Project description:With the increasing acknowledgment of the multifaceted roles of Anti-apoptotic Transcription Factor (AATF) in various cancers, our study directed its focus towards unraveling its implications in bladder cancer, particularly concerning the tumor microenvironment and immune landscape. We performed ChIP-seq to investigate the effect of AATF on chromatin status in BIU-87 cells.
Project description:Differentially expressed genes were identified by comparing the gene expression profiling of BIU-87 of AATF silencing with that of control. Results provide important information to indicate Effect of AATF silencing on BIU-87.
Project description:Human nephronophthisis and related ciliopathies suggest a link between ciliary signaling defects and altered DNA damage responses. The goal of our study is to elucidate the molecular link of both signaling systems as well as the role of altered DNA damage responses in kidney degeneration and fibrosis. The kinase-regulated DNA damage response target Apoptosis Antagonizing Transcription Factor (Aatf) is a master regulator of the p53 response. Upon genetic deletion of Aatf in renal tubular cells we induce progressive renal failure and a phenotype closely resembling human nephronophthisis in mice and are able to show Aatf as a regulator of primary cilia and modulator of the DNA damage response connecting two pathogenetic concepts of nephronophthisis and nephronophthisis-related ciliopathies. The analysis of the RNA-sequencing of four Aatf-knockout mice and four wildtype mice supports the experimental findings.
Project description:We investigated the interactions of AATF/Che1 with paraspeckles complex in Multiple Myeloma(MM) cells by looking at its relationship with lncRNA NEAT1_1(NEAT1) and the essential paraspeckles proteins. By analyzing ChIP- and ChIRP-sequencing of MM cells, we assessed that the interaction between AATF/Che1 and NEAT1 occurs also onto DNA and detected the sites where they co-localize. To better characterize the interaction, we studied the effects of interfering AATF/Che1 or NEAT1 on co-localizing sites through ChIP-seq with NEAT1 interfered (GapmerNEAT1) and ChIRP-seq with AATF/Che1 interfered (siChe). We found that NEAT1 is essential in maintaining the paraspeckles complex onto those sites. Moreover, by exploring DRIP-seq data with siChe, we also detected that AATF/Che1 and NEAT1 localize on R-loops, RNA:DNA hybrid structure involved in DNA transcription and repair. A depletion of AATF/Che1 causes a further increase of those hybrid structures and the activation of the immune response in MM, in particular the interferon (IFN) activation. To further explore these findings, we performed RNA-seq with siChe and GapmerNEAT1 which confirm that AATF/Che-1 down-regulation induces a strong up-regulation of genes involved in IFN response.
Project description:AATF is a predominantly nuclear protein that has been shown to be an apoptosis-inhibiting factor essential for both embryonic development and tumor growth. Several studies have shown a role of AATF in the modulation of pivotal cellular signal transduction pathways such as p53-, mTOR- and HIF-signaling. However, the exact molecular functions underlying its essential nature to cell proliferation and survival have remained elusive. Interestingly, several lines of evidence point towards a pivotal role of this protein in ribosome biogenesis and the maturation of ribosomal RNA. The function of AATF in this process is not clear, especially since the identity of the RNA-binding protein that links the AATF-containing protein complex (ANN) to rRNA precursors is unknown. In this study, we identify AATF in a screen for RNA-binding proteins. Importantly, AATF does not only bind to polyA-tailed RNA but CLIP-experiments reveal its association with ribosomal RNA. The RNA-binding domain of AATF is essential to maintain its positive effect on cellular rRNA levels. Furthermore, AATF binds to both mRNAs encoding for ribosome biogenesis factors as well as proteins involved with this process indicating AATF to be a central hub for the coordination of ribosome maturation. Consequently, our data for the first time identify the molecular basis to the role of AATF in ribosome biosynthesis and corroborate the link between tumorigenesis and ribosome biology.
Project description:Multiple myeloma is a hematological neoplasm of plasma cells characterized by an abnormal production of immunoglobulins. Che-1/AATF (Che-1) is an RNA binding protein involved in transcription regulation and highly expressed in this malignancy. In order to better characterize its functions in this type of disease, we performed co-immunoprecipitation experiments coupled with a mass-spec analysis by using total MM Kms27 cell lysates. From this analysis we were able to identify more than 600 proteins significantly enriched in Che-1 precipitates. As expected from its role in ribosomal RNA maturation, the Che-1 interactome contains numerous proteins involved in pre-rRNA processing and several ribosomal proteins. Notably, among other proteins interacting with Che-1, we identified many essential components of the paraspeckle which play an important role in the regulation of gene expression.
Project description:Estrogen Receptor alpha (ERα) is a key driver of most breast cancers, and it is the target of endocrine therapies used in the clinic to treat women with ERα positive (ER+) breast cancer. The two methods ChIP-seq (chromatin immunoprecipitation coupled with deep sequencing) and RIME (Rapid Immunoprecipitation of Endogenous Proteins) have greatly improved our understanding of ERα function during breast cancer progression and in response to anti-estrogens. A critical component of both ChIP-seq and RIME protocols is the antibody that is used to pull down the bait protein. To date, most of the ChIP-seq and RIME experiments for the study of ERα have been performed using the sc-543 antibody from Santa Cruz Biotechnology. However, this antibody has been discontinued, thereby severely impacting the study of ERα in normal physiology as well as diseases such as breast cancer and ovarian cancer. Here, we compare the sc-543 antibody with other commercially available antibodies, and we show that 06-935 (EMD Millipore) and ab3575 (Abcam) antibodies can successfully replace the sc-543 antibody for ChIP-seq and RIME experiments.