ABSTRACT: Proteomic expression analysis of Ca. Lokiarchaeum ossiferum, strain B36, grown using casein hydrolysate as the main carbon source under anaerobic conditions
Project description:Proteomic expression analysis of Ca. Lokiarchaeum ossiferum, strain B35, grown using casein hydrolysate as the main carbon source under anaerobic conditions
Project description:Peptide fingerprinting to verify the efficacy of phosphatase inhibitor beads (PIBs) for capturing Spodoptera frugiperda (Sf9) phosphatases of the PP2A family.
Project description:We aimed to identify proteins that would be turned over upon artificial tethering of WIPI2 to the mitochondrial surface upon rapalog treatment, using the FIS1-FRB plus FKBP-GFP-WIPI2 tethering system. We had previously observed that this induces mitophagy based on flow cytometry analysis of the mt-mKeima probe. Here, we aimed to identify which proteins are degraded upon 24 h Rapalog treatment and verified whether there was an enrichment of mitochondrial proteins being selectively turned over by mitophagy under these conditions in wild-type and NIX/BNIP3 double-knockout HeLa cells.
Project description:We aimed to identify proteins that would be turned over upon DFP treatment, a small molecule that mimicks hypoxia treatment and which induces NIX/BNIP3 mitophagy. We aimed to identify which proteins are degraded upon 24 h DFP treatment and verified whether there was an enrichment of mitochondrial proteins being selectively turned over by mitophagy under these conditions.
Project description:The androgen receptor (AR) is a critical driver of prostate cancer (PCa). To study regulators of AR protein levels and oncogenic activity, we created the first live cell quantitative endogenous AR fluorescent reporters. Leveraging this novel AR reporter, we performed genome-scale CRISPRi flow cytometry sorting screens to systematically identify genes that modulate AR protein levels. We identified and validated known AR protein regulators including HOXB13 and GATA2 and also unexpected top hits including PTGES3, a poorly characterized gene in PCa. PTGES3 repression resulted in loss of AR protein, cell cycle arrest, and cell death in AR-driven PCa models. PTGES3 is not a commonly essential gene, and our data nominate it as a prime PCa drug target. Clinically, analysis of PCa data demonstrate that PTGES3 expression is associated with AR directed therapy resistance. Mechanistically, we show PTGES3 binds directly to AR, forms a protein complex with AR in the nucleus, regulates AR protein stability in vitro and in vivo and modulates AR function in the nucleus at AR target genes. Lastly using a disulfide tethering fragment screen, we developed a PTGES3 covalent inhibitor that blocks the PTGES3/AR interaction and represses AR signaling in PCa cells, suggesting PTGES3 inhibitors may be a next generation AR-targeting therapeutic strategy that can overcome known mechanisms of resistance to existing AR-directed therapies in PCa.
Project description:The fidelity of immune responses depends on a timely controlled and selective mRNA degradation that is largely driven by RNA-binding proteins (RBPs). It remains unclear whether the selection of an individual mRNA molecule for degradation is governed by stochastic or directed processes. Here, we show that tristetraprolin (TTP, also known as ZFP36), an essential anti-inflammatory RBP, destabilizes target mRNAs via a hierarchical molecular assembly. The formation of the assembly strictly relies on the interaction of TTP with RNA. The TTP homolog ZFP36L1 exhibits similar requirements, indicating a broader relevance of this regulatory program. Unexpectedly, the assembly of the cytoplasmic mRNA-destabilization complex is licensed in the nucleus by TTP binding to pre-mRNA, while cytoplasmic mRNA does not constitute a de novo TTP target. Hence, the fate of an inflammation-induced mRNA is decided concomitantly with its synthesis. This mechanism prevents the translation of excessive and potentially harmful inflammation mediators, irrespective of transcription.
Project description:EndoC-bH1 cells were incubated with control siRNA or PCSK9 siRNA for 72 hours. The experiment was powered based PCSK9 knockdown in a pilot experiment. Sample size: 12x12.