Project description:Tau (MAPT) is a microtubule-associated protein causing frequent neurodegenerative diseases or inherited frontotemporal lobar degenerations. Emerging evidence for non-canonical functions of Tau in DNA protection and P53 regulation suggests its involvement in cancer. Indeed, Tau expression correlates with cancer-specific survival or response to microtubule therapeutics. These data may imply common molecular pathways involved in the pathogenesis of neurodegenerative disorders and cancer. To bring new evidence that Tau represents a key protein in cancer, we present an in silico pan-cancer analysis of MAPT transcriptomic profile in over 11000 clinical samples and over 1300 pre-clinical samples provided by the TCGA and the DEPMAP datasets respectively. We completed this analysis by exploring a possible interplay of MAPT with wild-type or mutated P53. Then, we calculated the impact of MAPT expression on clinical outcome and drug response. Overall, the results support a relevant role of the MAPT gene in several cancer types, although the contribution of Tau to cancer appears to very much depend on the cellular context.
Project description:A genome-wide CRISPR-Cas9 knockout screen was performed in the breast cancer cell lines T47D, MCF7, and CAMA-1 to identify genes modulating sensitivity and resistance to capivasertib, a selective AKT inhibitor. Cells were transduced with a CRISPR library, followed by treatment with capivasertib or vehicle control (DMSO). Guide RNA (sgRNA) enrichment and depletion were assessed via next-generation sequencing to determine gene-level effects on cell viability and drug response. Gene-level data are provided for the initial plasmid library, baseline, DMSO-treated controls, and post-capivasertib treatment across replicates.
Project description:Transcriptional regulation is tightly linked to chromatin organization, with H3K4me3 commonly marking both active and bivalent promoters. In embryonic stem cells (ESC), MLL2 is essential for H3K4me3 deposition at bivalent promoters, which has been proposed to facilitate the induction of major developmental genes during pluripotent cell differentiation. However, prior studies point to a functional discrepancy between the loss of H3K4me3 at bivalent promoters and the largely unaltered transcription of major developmental genes in Mll2-/- cells. In this study, we investigated MLL2-dependent gene regulation in mouse ESC and during their differentiation. Contrary to the prevailing view, we show that MLL2’s primary role is not to oppose Polycomb-mediated repression at the bivalent promoters of developmental genes. Instead, we identify a previously unrecognized regulatory function for MLL2 at the CG-rich 5' untranslated regions (5'UTR) of evolutionarily young LINE-1 (L1) transposable elements (TE). We found that MLL2 binds to the 5’UTR of L1 elements and is critical for maintaining their active state (H3K4me3 and H3K27ac), while preventing the accumulation of repressive H3K9me3. Using both global genomic approaches (i.e. RNA-seq, ChIP-seq and Micro-C) as well as targeted L1 deletions, we demonstrate that these MLL2-bound L1 elements act as enhancers, modulating the expression of neighboring genes in ESC and, more prominently, during differentiation. Together, our findings illuminate novel aspects of MLL2 regulatory function during early developmental transitions and highlight the emerging role of TE as key components of long-range gene expression control.
Project description:In this study, we used the murine (Mus musculus) medullary thymic epithelial cell line (mTEC 3.10 cell line) co-cultured with fresh thymocytes as a functional assay for mTEC-thymocyte adhesion. Then we analyzed the differential transcriptional profile of this cell line, by means of Agilent oligo microarray hybridization, comparing Autoimmune regulator (Aire) wild-type cells vs Crispr-Cas9-induced Aire KO cells. The comparative transcriptional expression signatures allowed us to find those differentially expressed mRNAs or lncRNAs between the samples tested.
Project description:CRISPR/Cas9 system was used to generate mediator complex subunit 1 (MED1) knockout human pre-B ALL cell line 697. RNA-seq was performed to observe the effects of MED1 deletion on gene expression in 697.
Project description:Plants as non-mobile organisms constantly integrate varying environmental signals to flexibly adapt their growth and development. Local fluctuations in water and nutrient availability, sudden changes in temperature or other abiotic and biotic stresses can trigger changes in the growth of plant organs. Multiple mutually interconnected hormonal signaling cascades act as essential endogenous translators of these exogenous signals in the adaptive responses of plants. Although the molecular backbones of hormone transduction pathways have been identified, the mechanisms underlying their interactions are largely unknown. Here, using genome wide transcriptome profiling we identify an unknown auxin and cytokinin cross-talk component; SYNERGISTIC ON AUXIN AND CYTOKININ1 (SYAC1), whose expression in roots is strictly dependent on both of these hormonal pathways. We show that SYAC1 is a component of secretory pathway, whose enhanced activity interferes with deposition of cell wall components and can fine-tune organ growth and sensitivity to soil pathogens
Project description:Annexin A1 (ANXA1) is a Ca2+-binding protein involved in pancreatic cancer (PC) progression. It is able to mediate cytoskeletal organization maintaining a malignant phenotype. ANXA1 Knock-Out (KO) MIA PaCa-2 cells partially lost their migratory and invasive capabilities and also the metastatization process is affected in vivo. Here, we investigated the microRNA (miRNA) profile in ANXA1 KO cells. The analysis of the modification in miRNA expression remarked the significant involvement of ANXA1 in PC progression. In this study, we focused on miR-196a which is a well known oncogenic factor in several tumour models and it appeared down-modulated in absence of ANXA1. Furthermore, both ANXA1 and miR-196a are able to trigger the mechanisms of the epithelial to mesenchymal transition (EMT). Our results show that the reintroduction of miR-196a through the mimic sequence restored the early aggressive phenotype of MIA PaCa-2. Then, ANXA1 seems to support the expression of miR-196a and its role. On the other hand, this miRNA is able to mediate some of protein functions in PC progression. This work elucidates the correlation between ANXA1 and specific miRNA sequences, particularly miR-196a, and provides new knowledge about the protein intracellular role.
Project description:Transcription and RNA processing are tightly coupled and precisely coordinated to ensure appropriate levels of mature transcripts. The C-terminal domain (CTD) of RNA polymerase II (Pol II) is phosphorylated differentially during the transcription cycle and serves as a landing pad for a variety of transcriptional regulators and RNA processing proteins. PHD finger protein 3 (PHF3) binds to the serine-2 phosphorylated Pol II CTD with its Spen Paralogue and Orthologue C-terminal (SPOC) domain and regulates transcription elongation and mRNA stability. Here we show that PHF3 binds target RNAs by recognizing a G-rich motif prone to form G-quadruplexes (G4s). Two PHF3 zinc finger domains, PHD (plant homeo domain) and TLD (TFIIS-like domain) act in concert to bind and destabilize target RNAs and their deletion in HEK293T cells causes massive deregulation of gene expression. Together these results establish PHF3 as a Pol II and an RNA-binding protein that coordinates transcription elongation with RNA decay to regulate neuronal gene expression.