Unknown,Transcriptomics,Genomics,Proteomics

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Expression data in C. elegans L2 larvae after nhr-23 inhibition and in controls

ABSTRACT: NHR-23, a conserved member of the nuclear receptor family of transcription factors, is required for normal development in C. elegans where it plays a critical role in growth and molting. In a search for NHR-23 dependent genes, we performed whole genome comparative expression microarrays on both control and nhr-23 inhibited synchronized larvae. Genes that decreased in response to nhr-23 RNAi included several collagen genes. Unexpectedly, several hedgehog-related genes were also down-regulated after nhr-23 RNAi. A homozygous nhr-23 deletion allele was used to confirm the RNAi knockdown phenotypes and the changes in gene expression. Our results indicate that NHR-23 is a critical coregulator of functionally linked genes involved in growth and molting and reveal evolutionary parallels among the ecdysozoa. Synchronized populations of L1 larvae were plated with two sets of HT115 bacteria, one that had been transformed with the RNAi vector only (L4440 plasmid) and another that had been transformed with a vector targeting nhr-23 (clone 5174) [Proc Natl Acad Sci USA 98 (2001) 7360-7365]. Worms were kept on 2% agarose plates for 21 hr at 20C, collected, and approximately 200ml of worms resuspended in PBS were used in each individual experiment. Total RNA was isolated from frozen pellets using a Mixer-Mill (Miller-Mill 300) following an RNeasy Mini Kit (Qiagen, Germantown, MD) according to manufacturer protocol. Aliquots of cultures used for RNA isolation were kept on nhr-23 RNAi plates to confirm the knockdown phenotypic changes occurred during subsequent molts.

ORGANISM(S): Caenorhabditis elegans

SUBMITTER: WeiPing Chen

PROVIDER: E-GEOD-32031 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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