Expression analysis of WS4303 (wild type) vs WS5041 (mir-58 mutants) total mRNA

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.