Project description:Although DNA motifs recognized by the transcription factors (TFs) have been determined, challenges remain in probing in vivo architecture of TF-DNA complexes on a genome-wide scale. Here, we show in vivo architecture of Escherichia coli arginine repressor (ArgR)-DNA complexes using chromatin immunoprecipitation coupled with sequencing (ChIP-exo). The identified 62 ArgR-binding loci were classified into three groups, comprised of single, double, and triple peak-pairs, respectively. Each peak-pair has unique 93 bp-long (±2 bp) ArgR-binding sequence containing two ARG boxes (39 bp) and residual sequence. Moreover, the peak-pairs provided the three ArgR-binding modes defined by the position of the two ARG boxes, indicating that the formation of DNA bending apparently centered between the pair of ARG boxes facilitates the non-specific contacts between ArgR subunits and the residual sequences. Thus, our data postulate the in vivo architecture of ArgR-DNA complexes to understand its transcription regulatory mechanism. ChIP-exo profiles of ArgR (+Arginine) and ArgR (-Arginine) were generated by deep sequencing in duplicates using Illumina MiSeq.
Project description:The C-terminal domain (CTD) of the RNA polymerase II (RNAPII) subunit POLR2A is a platform for modifications specifying the recruitment of factors that regulate transcription, mRNA processing, and chromatin remodeling. Here, we show that a CTD arginine residue (R1810 in human) that is conserved across vertebrates is symmetrically dimethylated (me2s). This R1810me2s modification requires Protein Arginine Methyltransferase 5 (PRMT5) and recruits the Tudor domain of the Survival of Motor Neuron (SMN) protein, which is mutated in spinal muscular atrophy (SMA). SMN interacts with Senataxin, which is sometimes mutated in Ataxia Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis (ALS4). Because R1810me2s and SMN, like Senataxin, are required for resolving RNA-DNA hybrids, created by RNA polymerase II, that form â??R-loopsâ?? in transcription termination regions, we propose that R1810me2s, SMN, and Senataxin are components of a pathway for R-loop resolution in which defects can influence transcription termination and may contribute to neurodegenerative disorders. ChIP of RNAPII in Raji cells expressing shRNG against SMN or GFP; ChIP against RNAPII in Raji cells where endogenous RNAPII has been replaced with wt or R1810A mutant amanitin-resistant protein; and ChIP of SMN in HEK293 cells.
Project description:Arginine is involved in inflammation and amino acid signaling, in part through the mTORC1 pathway. In cell-based assays and in the mouse, we found that arginine regulates nuclear levels of arginyl-tRNA synthetase (ArgRS) and that nuclear ArgRS interacts and co-localizes with the Serine/Arginine Repetitive Matrix Protein 2 (SRRM2), a spliceosomal protein crucial for the formation of nuclear speckle condensates. Arginine depletion or ArgRS knock down, both of which decreased nuclear ArgRS levels, mobilized SRRM2 for trafficking from nuclear condensates and altered mRNA processing and splice junction usage while minimally affecting expression of other cellular RNAs. These splice junction changes included a subset that were inversely correlated with SRRM2 knock down induced changes and the affected genes encompassed components of the mTORC1 pathway. This inverse correlation suggests that the nuclear ArgRS-SRRM2 interaction regulates SRRM2 nuclear trafficking and alternative splicing in the physiological response to changed arginine levels resulting from inflammation.
Project description:The human genome encodes a family of nine protein arginine methyltransferases (PRMT1-9). Different members of this enzyme family catalyze different types of protein methylation at the terminal nitrogen atoms of arginine residues, forming monomethylated arginine (MMA), asymmetrically dimethylated arginine (ADMA) and symmetrically dimethylated arginine (SDMA). The last member of this family, PRMT9, is characterized in detail here. We identify two spliceosome-associated proteins, SAP145 (SF3B2) and SAP49 (SF3B4), as PRMT9 binding partners, linking PRMT9 to U2snRNP maturation. We show that SAP145 is methylated by PRMT9 at arginine 508 (R508). Amino acid analysis and a methyl-specific antibody revealed the formation of MMA and SDMA, and PRMT9 thus joins PRMT5 as the only mammalian enzymes that can deposit the SDMA mark. Methylation of the SAP145R508 generates a binding site for the Tudor domain of SMN, and RNA-seq analysis reveals gross splicing changes when PRMT9 levels are attenuated. These studies identify PRMT9 as a non-histone methyltransferase that primes the U2snRNP for interaction with SMN. RNA sequencing was carried out using RNA samples from two biological replicates of control and PRMT9 knockdown HeLa cells.
Project description:The C-terminal domain (CTD) of the RNA polymerase II (RNAPII) subunit POLR2A is a platform for modifications specifying the recruitment of factors that regulate transcription, mRNA processing, and chromatin remodeling. Here, we show that a CTD arginine residue (R1810 in human) that is conserved across vertebrates is symmetrically dimethylated (me2s). This R1810me2s modification requires Protein Arginine Methyltransferase 5 (PRMT5) and recruits the Tudor domain of the Survival of Motor Neuron (SMN) protein, which is mutated in spinal muscular atrophy (SMA). SMN interacts with Senataxin, which is sometimes mutated in Ataxia Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis (ALS4). Because R1810me2s and SMN, like Senataxin, are required for resolving RNA-DNA hybrids, created by RNA polymerase II, that form ‘R-loops’ in transcription termination regions, we propose that R1810me2s, SMN, and Senataxin are components of a pathway for R-loop resolution in which defects can influence transcription termination and may contribute to neurodegenerative disorders.
Project description:Intervention type:DRUG. Intervention1:Huaier, Dose form:GRANULES, Route of administration:ORAL, intended dose regimen:20 to 60/day by either bulk or split for 3 months to extended term if necessary. Control intervention1:None.
Primary outcome(s): For mRNA libraries, focus on mRNA studies. Data analysis includes sequencing data processing and basic sequencing data quality control, prediction of new transcripts, differential expression analysis of genes. Gene Ontology (GO) and the KEGG pathway database are used for annotation and enrichment analysis of up-regulated genes and down-regulated genes.
For small RNA libraries, data analysis includes sequencing data process and sequencing data process QC, small RNA distribution across the genome, rRNA, tRNA, alignment with snRNA and snoRNA, construction of known miRNA expression pattern, prediction New miRNA and Study of their secondary structure Based on the expression pattern of miRNA, we perform not only GO / KEGG annotation and enrichment, but also different expression analysis.. Timepoint:RNA sequencing of 240 blood samples of 80 cases and its analysis, scheduled from June 30, 2022..