Project description:RNAs interact with networks of proteins to form complexes (RNPs) that govern many biological processes, but inter-protein networks on RNA are currently impossible to examine in a comprehensive way. We developed a live-cell RNP-MaP (RNP network analysis by mutational profiling) chemical probing strategy for mapping simultaneous binding by and cooperative interactions among multiple proteins with single RNA molecules at nucleotide resolution. RNP-MaP revealed that two structurally related, but sequence-divergent noncoding RNAs, RNase P and RMRP, share nearly identical RNP networks and, further, that protein-mediated structural communication identifies function-critical network hubs in these RNAs. RNP-MaP identified previously unknown protein interaction networks within the XIST long noncoding RNA that are conserved between mouse and human RNAs and defined silencing, compartmentalization and splicing communities of proteins whose binding sites are networked together on XIST. The XIST E region contains a dense network of protein interactions, and including PTBP1, MATR3, and TIA1 proteins , which RNP-MaP revealed to each bind the XIST E region via two distinct interaction modes.; Depletion of PTBP1 and MATR3 caused native XIST particles to disperse and disappear in a human cell line. the The highly networked XIST E region was sufficient to mediate XIST RNA-like foci formation in cells. RNP-MaP enables discovery and prioritization of in-cell protein interaction networks critical for function in long RNAs, in the absence of pre-existing knowledge about protein binding sites.
Project description:RNA binding proteins (RBPs) control varied processes, including RNA splicing, stability, transport, and translation. Dysfunctional RNA-RBP interactions contribute to the pathogenesis of human disease, however, characterizing the nature and dynamics of multiprotein assemblies on RNA has been challenging. To address this, non-isotopic ligation-based ultraviolet crosslinking immunoprecipitation was combined with mass spectrometry (irCLIP-RNP) to identify RNA-dependent associated proteins (RDAPs) co-bound to RNA with any RBP of interest. irCLIP-RNP defined landscapes of multimeric protein assemblies on RNA, uncovering previously unknown patterns of RBP-RNA associations, including cell-type-selective combinatorial relationships between RDAPs and primary RBPs. irCLIP-RNP also defined dynamic RDAP remodeling in response to epidermal growth factor (EGF), uncovering EGF-induced recruitment of UPF1 adjacent to HNRNPC to effect splicing surveillance of cell proliferation mRNAs. To identify the RNAs simultaneously co-bound by multiple studied RBPs, a sequential immunoprecipitation irCLIP (Re-CLIP) method was also developed. Re-CLIP confirmed binding relationships seen in irCLIP-RNP and identified HNRNPC and UPF1 RBP co-binding on RND3 and DDX3X mRNAs. irCLIP-RNP and Re-CLIP provide a framework to identify and characterize dynamic RNA-protein assemblies in living cells.
Project description:RNA binding proteins (RBPs) control varied processes, including RNA splicing, stability, transport, and translation. Dysfunctional RNA-RBP interactions contribute to the pathogenesis of human disease, however, characterizing the nature and dynamics of multiprotein assemblies on RNA has been challenging. To address this, non-isotopic ligation-based ultraviolet crosslinking immunoprecipitation was combined with mass spectrometry (irCLIP-RNP) to identify RNA-dependent associated proteins (RDAPs) co-bound to RNA with any RBP of interest. irCLIP-RNP defined landscapes of multimeric protein assemblies on RNA, uncovering previously unknown patterns of RBP-RNA associations, including cell-type-selective combinatorial relationships between RDAPs and primary RBPs. irCLIP-RNP also defined dynamic RDAP remodeling in response to epidermal growth factor (EGF), uncovering EGF-induced recruitment of UPF1 adjacent to HNRNPC to effect splicing surveillance of cell proliferation mRNAs. To identify the RNAs simultaneously co-bound by multiple studied RBPs, a sequential immunoprecipitation irCLIP (Re-CLIP) method was also developed. Re-CLIP confirmed binding relationships seen in irCLIP-RNP and identified HNRNPC and UPF1 RBP co-binding on RND3 and DDX3X mRNAs. irCLIP-RNP and Re-CLIP provide a framework to identify and characterize dynamic RNA-protein assemblies in living cells.
Project description:RNA-seq analysis of primary hepatocytes isolated from C57BL/6N mice, stimulated with IL-1β recombinant protein to examine the transcriptional response to inflammatory signaling.
Project description:C. elegans GLD-2 forms an active PAP with multiple RNA-binding partners to regulate diverse aspects of germline and early embryonic development. One GLD-2 partner, RNP-8, was previously shown to influence oocyte fate specification. To identify transcripts selectively associated with both GLD-2 and RNP-8, we employ a genomic approach using the method of RNA immunoprecipitation followed by microarray analysis (RIP-chip). We used microarrays to identify mRNAs selectively associated with either GLD-2 or RNP-8. Worm extracts were prepared from synchronized adult C. elegans (15 h after L4 stage). For GLD-2 IP, an immoblized anti-GLD-2 antibody was then used to purify the GLD-2 complexes from either wild-type (N2) or gld-2(RNAi) worm extracts. RNA was then extracted from the pellets and analyzed on C.elegans Affymetrix genechip. Four biological replicates were performed, each sample processed in parallel. For RNP-8 IP, an immoblized anti-RNP-8 antibody was then used to purify the RNP-8 complexes from either wild-type (N2) or rnp-8(q784) worm extracts and three biological replicates were performed. For wt or gld-2(RNAi) samples, total RNA was extracted from worm extracts and hybridized on C.elegans Affymetrix genechip.
Project description:C. elegans GLD-2 forms an active PAP with multiple RNA-binding partners to regulate diverse aspects of germline and early embryonic development. One GLD-2 partner, RNP-8, was previously shown to influence oocyte fate specification. To identify transcripts selectively associated with both GLD-2 and RNP-8, we employ a genomic approach using the method of RNA immunoprecipitation followed by microarray analysis (RIP-chip). We used microarrays to identify mRNAs selectively associated with either GLD-2 or RNP-8.
Project description:Recombinant Escherichia coli cultures are used to manufacture numerous therapeutic proteins and industrial enzymes, where many of these processes use elevated temperatures to induce recombinant protein production. The heat-shock response in wild-type E. coli has been well studied. In this study, the transcriptome profiles of recombinant E. coli subjected to a heat-shock and to a dual heat-shock recombinant protein induction were examined. Most classical heat-shock protein genes were identified as regulated in both conditions. The major transcriptome differences between the recombinant and reported wild-type cultures were heavily populated by hypothetical and putative genes, which indicates recombinant cultures utilize many unique genes to respond to a heat-shock. Comparison of the dual stressed culture data with literature recombinant protein induced culture data revealed numerous differences. The dual stressed response encompassed three major response patterns: induced-like, in-between, and greater than either individual stress response. Also, there were no genes that only responded to the dual stress. The most interesting difference between the dual stressed and induced cultures was the amino acid-tRNA gene levels. The amino acid-tRNA genes were elevated for the dual cultures compared to the induced cultures. Since tRNAs facilitate protein synthesis via translation, this observed increase in amino acid-tRNA transcriptome levels, in concert with elevated heat-shock chaperones, might account for improved productivities often observed for thermo-inducible systems. Most importantly, the response of the recombinant cultures to a heat-shock was more profound than wild-type cultures, and further, the response to recombinant protein induction was not a simple additive response of the individual stresses. The objective of the present work is to gain a better understanding of the heat-shock response in recombinant cultures and how this response might impact recombinant protein production. To accomplish this objective, the transcriptome response of recombinant cultures subjected to a heat-shock and a dual heat-shock recombinant protein induction were analyzed. The transcriptome levels were determined using Affymetrix E. coli Antisense DNA microarrays, such that the entire genome was evaluated. These two transcriptome responses were also compared to recombinant cultures at normal growth temperature that were not over-expressing the recombinant protein and a set of literature recombinant culture data that were chemically induced to over-express the recombinant protein. Additionally, the heat-shock response of the recombinant cultures was compared to the literature report of the heat-shock response in wild-type cultures. The results of the global transcriptome analysis demonstrated that recombinant cultures respond differently to a heat-shock stress than wild-type cultures, where the transcriptome response of the recombinant cultures is further modified by production of a recombinant protein.
Project description:Analysis of human hepatic stellate cell line LX2 stimulated for 24h in serum-free DMEM medium containing 0 or 50 ng/ml recombinant human GDF2 protein. Results provide insight into the activation effects of GDF2 on human hepatic stellate cell. We used microarrays to detail the global programme of gene expression underlying activation of hepatic stellate cells and identified liver-fibrosis-related genes genes during this process.
Project description:Canine keratinocyte cell line (CPEK, CELLnTEC Advanced Cell Systems, Bern, Switzerland) : Unstimulated control (UC) vs. Samples stimulated by 4µg/mL recombinant human periostin (PO) (R&D Systems, Minneapolis, MN) for 6 or 24 hrs.