Project description:RIP-chip-SRM : a New Combinatorial Large Scale Approach Identifies a Set of Translationally Regulated bantam/miR 58 Targets in C. elegans RNA binding protein immunopurification + microarray + targeted protein quantification via Selected Reaction Monitoring This SuperSeries is composed of the following subset Series: GSE32941: Purification of TAP::ALG-1 complexes and associated RNA from mixed-stage TAP::ALG-1 transgenic (WS4303) and wild-type (N2) animals GSE32942: Microarray analysis of TAP::ALG-1 associated RNAs isolated from synchronized 'wild-type' animals and 'mir-58' mutants GSE32943: Expression analysis of WS4303 (wild type) vs WS5041 (mir-58 mutants) total mRNA Refer to individual Series
Project description:To discover new miRNA targets, we generated a C. elegans transgenic line expressing a functional N-terminally Tandem Affinity Purification (TAP) tagged ALG-1 protein (C. elegans strain WS4303). We crossed the TAP::ALG-1 transgene into the mir-58(n4640) mutant background to generate the strain WS5041. For simplicity, we will hereafter term the TAP::ALG-1 transgenic animals as wild typeand the transgenic WS5041 animals as mir-58. We compared the mRNA population that coimmunopurified with TAP::ALG-1 from synchronized L4 stage wild-type animals with that from synchronized L4 stage mir-58 mutant animals by one-color Affymetrix gene arrays. miR-58 target mRNAs should be specifically underrepresented in the latter samples.
Project description:To discover new miRNA targets, we generated a C. elegans transgenic line expressing a functional N-terminally Tandem Affinity Purification (TAP) tagged ALG-1 protein (C. elegans strain WS4303). We crossed the TAP::ALG-1 transgene into the mir-58(n4640) mutant background to generate the strain WS5041. For simplicity, we will hereafter term the TAP::ALG-1 transgenic animals as wild typeand the transgenic WS5041 animals as mir-58. We compared the mRNA population that coimmunopurified with TAP::ALG-1 from synchronized L4 stage wild-type animals with that from synchronized L4 stage mir-58 mutant animals by one-color Affymetrix gene arrays. miR-58 target mRNAs should be specifically underrepresented in the latter samples. Strains WS4303 (wt) and WS5041 (mir-58) were used for TAP::ALG-1 IPs. All experiments were conducted in three independent replicates. For each replicate, WS4303 and WS5041 were grown in parallel. 150 ng of TAP::ALG-1 associated RNA isolated from synchronized late L4 animals were sent to the GeneCore facilty in Heidelberg, Germany (http://www.genecore.embl.de/index.cfm), and the microarray data were generated according to their standard protocol (Weinmann et al. 2009).
Project description:To discover new miRNA targets, we generated a C. elegans transgenic line expressing a functional N-terminally Tandem Affinity Purification (TAP) tagged ALG-1 protein (C. elegans strain WS4303). We crossed the TAP::ALG-1 transgene into the mir-58(n4640) mutant background to generate the strain WS5041. For simplicity, we will hereafter term the TAP::ALG-1 transgenic animals as “wild type” and the transgenic WS5041 animals as “mir-58”. In addition to immunopurifying the TAP::ALG-1 and associated RNAs from these strains, we also compared total mRNA levels between these two strains.
Project description:To discover new miRNA targets, we generated a C. elegans transgenic line expressing a functional N-terminally Tandem Affinity Purification (TAP) tagged ALG-1 protein (C. elegans strain WS4303). We crossed the TAP::ALG-1 transgene into the mir-58(n4640) mutant background to generate the strain WS5041. For simplicity, we will hereafter term the TAP::ALG-1 transgenic animals as “wild type” and the transgenic WS5041 animals as “mir-58”. In addition to immunopurifying the TAP::ALG-1 and associated RNAs from these strains, we also compared total mRNA levels between these two strains. Total RNA was isolated from the same WS4303 and WS5041 total extracts that was further used for the TAP::ALG-1 RIP. Three independent biological replicates were analyzed. Long-oligo whole-genome C. elegans arrays, produced by the Genome Sequencing Center at Washington University in St. Louis (http://genome.wustl.edu/genome/celegans/microarray/ma_gen_info.cgi), were used for these experiments. A total of 10 µg of total RNA was used for cDNA synthesis.
Project description:MicroRNAs are regulators of gene expression whose functions are critical for normal development and physiology. We have previously characterized mutations in a Caenorhabditis elegans microRNA-specific Argonaute ALG-1 (Argonaute-like gene) that are antimorphic [alg-1(anti)]. alg-1(anti) mutants have dramatically stronger microRNA-related phenotypes than animals with a complete loss of ALG-1. ALG-1(anti) miRISC (microRNA induced silencing complex) fails to undergo a functional transition from microRNA processing to target repression. To better understand this transition, we characterized the small RNA population associated with ALG-1(anti) complexes in vivo. alg-1(anti) mutants dramatically overaccumulated microRNA* (passenger) strands, and immunoprecipitated ALG-1(anti) complexes contained nonstoichiometric yields of mature microRNA and microRNA* strands, with some microRNA* strands present in the ALG-1(anti) Argonaute far in excess of the corresponding mature microRNAs. We show complex and microRNA-specific defects in microRNA strand selection and microRNA* strand disposal. For certain microRNAs (for example mir-58), microRNA guide strand selection by ALG-1(anti) appeared normal, but microRNA* strand release was inefficient. For other microRNAs (such as mir-2), both the microRNA and microRNA* strands were selected as guide by ALG-1(anti), indicating a defect in normal specificity of the strand choice. Our results suggest that wild-type ALG-1 complexes recognize structural features of particular microRNAs in the context of conducting the strand selection and microRNA* ejection steps of miRISC maturation. Deep-sequencing was performed on cDNA libraries made from total RNA and RNA immunoprecipitated with ALG-1 from mixed-staged populations of three strains: three biological replicates from wild-type animals and two biological replicates each from alg-1(ma192) and alg-1(ma202) mutant animals. In addition, deep-sequencing was performed on cDNA libraries made from L2-staged total RNA in two biological replicates from wildtype and alg-1(ma202) animals and one biological replicate of alg-1(ma192).
Project description:MicroRNAs are regulators of gene expression whose functions are critical for normal development and physiology. We have previously characterized mutations in a Caenorhabditis elegans microRNA-specific Argonaute ALG-1 (Argonaute-like gene) that are antimorphic [alg-1(anti)]. alg-1(anti) mutants have dramatically stronger microRNA-related phenotypes than animals with a complete loss of ALG-1. ALG-1(anti) miRISC (microRNA induced silencing complex) fails to undergo a functional transition from microRNA processing to target repression. To better understand this transition, we characterized the small RNA population associated with ALG-1(anti) complexes in vivo. alg-1(anti) mutants dramatically overaccumulated microRNA* (passenger) strands, and immunoprecipitated ALG-1(anti) complexes contained nonstoichiometric yields of mature microRNA and microRNA* strands, with some microRNA* strands present in the ALG-1(anti) Argonaute far in excess of the corresponding mature microRNAs. We show complex and microRNA-specific defects in microRNA strand selection and microRNA* strand disposal. For certain microRNAs (for example mir-58), microRNA guide strand selection by ALG-1(anti) appeared normal, but microRNA* strand release was inefficient. For other microRNAs (such as mir-2), both the microRNA and microRNA* strands were selected as guide by ALG-1(anti), indicating a defect in normal specificity of the strand choice. Our results suggest that wild-type ALG-1 complexes recognize structural features of particular microRNAs in the context of conducting the strand selection and microRNA* ejection steps of miRISC maturation.
Project description:The Argonautes (AGOs) are widely expressed, evolutionarily conserved RNA binding proteins that play an important role in gene expression regulation. The AGOs bind to small regulatory noncoding RNAs such as micro RNAs (miRNAs), short interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs) etc. The small regulatory noncoding RNAs serve the function of guiding the AGOs to the right target RNAs by complementary base pairing. Additionally, the AGOs interact with GW182 (TNRC6A/-B/-C) proteins and together with small RNAs, they form an effector ribonucleo protein complex named, RNA Induced Silencing Complex (RISC) that regulates several aspects of transcriptional and post-transcriptional gene expression. ALG-1 (Argonaute Like Gene) and ALG-2 are the AGO proteins in C. elegans that are required for miRNA mediated gene expression regulation. Our efforts towards the characterization of the protein complexes comprised of ALG-1 led to the identification of DPF-3, a conserved protease belonging to clinically relevant Di Peptidyl Peptidase IV family, as the novel interacting partner of ALG-1. We have further explored the role of DPF-3 in AGO regulation.