Project description:Integrase CLIP-seq experiments were conducted on wild-type and eccentric HIV-1 virions generated in the presence of allosteric integrase inhibitors and IN K264/266A and R269/K273A mutations Integrase CLIP-seq experiments were conducted by immunoprecipitation of integrase-RNA complexes from fully formed mature and eccentric virus particles. Libraries of RNA molecules bound by integrase were generated and sequenced by Illumina Hi-Seq2000 and 2500 platforms.
Project description:The identification of RNAs that are recognized by RNA-binding proteins (RNA-BPs) using techniques such as Crosslinking and Immunoprecipitation (CLIP) has revolutionized the genome-wide discovery of RNA-BP RNA targets. Among the different versions of CLIP that have been developed, the use of photoactivable nucleoside analogs has resulted in high efficiency photoactivable ribonucleoside-enhanced CLIP (PAR-CLIP) in vivo. Nonetheless, PAR-CLIP has not yet been applied in prokaryotes. To determine if PAR-CLIP can be used in prokaryotes, we determined suitable conditions for the incorporation of 4-thiouridine (4SU), a photoactivable nucleoside, into E. coli RNA and for the isolation of RNA crosslinked to RNA-BPs of interest. Applying this technique to Hfq, a well-characterized regulator of small RNA (sRNA)-messenger RNA (mRNA) interactions, we showed that PAR-CLIP identified most of the known sRNA targets of Hfq, as well as functionally relevant sites of Hfq-mRNA interactions at nucleotide resolution. Based on our findings, PAR-CLIP represents an improved method to identify both the RNAs and the specific regulatory sites that are recognized by RNA-BPs in prokaryotes.
Project description:UV cross-linking and immunoprecipitation (CLIP) and individual-nucleotide resolution CLIP (iCLIP) are the most frequently used methods to study protein-RNA interactions in the intact cells and tissues, but their relative advantages or inherent biases have not been evaluated. To benchmark CLIP and iCLIP method, we performed iCLIP with Nova protein, which is the most extensively studied protein by CLIP. Further, we assessed UV-C-induced cross-linking preferences, by exploiting the UV-independent formation of covalent RNA cross-links of the mutant RNA methylase NSUN2.
Project description:RNA binding proteins (RBPs) are essential for RNA metabolism and have profound impacts in both health and disease. The subcellular organization of RBP interaction networks with target RNAs remains largely unexplored. Here, we develop colocalization CLIP, a method that combines CrossLinking and ImmunoPrecipitation (CLIP) with proximity labeling, to explore in-depth the subcellular RNA interactions of the well-studied RNA-binding protein HuR. Using this method, we uncover HuR's dynamic and location-specific interactions with RNA, revealing alterations in sequence preferences and interactions in the nucleus, cytosol, or stress granule compartments. We uncover HuR's unique binding preferences within stress granules during arsenite stress, illuminating intricate interactions that conventional methodologies cannot capture. Overall, coCLIP provides a powerful method for revealing RBP:RNA interactions based on localization, and lays the foundation for an advanced understanding of RBP models that incorporate subcellular location as a critical determinant of their functions.
Project description:Integrase CLIP-seq experiments were conducted on wild-type and eccentric HIV-1 virions generated in the presence of allosteric integrase inhibitors and IN K264/266A and R269/K273A mutations
Project description:We analyze the protein-RNA interactions of HDAC9 and BRG1 in human aortic smooth muscle cells overexpressing mutant aneurysm alleles (TGFBR2G357W and ACTA2R179H) and wild-type cells using CLIP-seq.
Project description:RNA binding proteins (RBPs) are essential for RNA metabolism and have profound impacts in both health and disease. The subcellular organization of RBP interaction networks with target RNAs remains largely unexplored. Here, we develop colocalization CLIP, a method that combines CrossLinking and ImmunoPrecipitation (CLIP) with proximity labeling, to explore in-depth the subcellular RNA interactions of the well-studied RNA-binding protein HuR. Using this method, we uncover HuR's dynamic and location-specific interactions with RNA, revealing alterations in sequence preferences and interactions in the nucleus, cytosol, or stress granule compartments. We uncover HuR's unique binding preferences within stress granules during arsenite stress, illuminating intricate interactions that conventional methodologies cannot capture. Overall, coCLIP provides a powerful method for revealing RBP:RNA interactions based on localization, and lays the foundation for an advanced understanding of RBP models that incorporate subcellular location as a critical determinant of their functions.
Project description:UV-crosslinking and immunoprecipitation (CLIP) combined with high-throughput sequencing was previously used to generate transcriptome-wide binding maps of several RNA-binding proteins9-12. However, since identification of binding sites relied on the analysis of overlapping sequence clusters, distances of less than 30 nucleotides were not resolved. An additional disadvantage of CLIP is the requirement of reverse transcription to pass over residual amino acids that remain covalently attached to the RNA at the crosslink site. Primer extension assays have shown that the vast majority of cDNAs prematurely truncate immediately before the 'crosslink nucleotide'13. Here, we exploited this apparent limitation to achieve single nucleotide resolution by capturing these truncated cDNAs through the introduction of a second adapter after reverse transcription via self-circularization. In order to quantify cDNA molecules that truncate at the same nucleotide, we added a random barcode to the DNA adapter. This allowed us to discriminate between unique cDNA products and PCR duplicates . Taken together, individual-nucleotide resolution CLIP (iCLIP) enables precise mapping of protein-RNA interactions in intact cells.