The microRNA miR-124 controls gene expression in the sensory nervous system of Caenorhabditis elegans.
miR-124 is a highly conserved microRNA (miRNA) whose in vivo function is poorly understood. Here, we identify miR-124 targets based on the analysis of the first mir-124 mutant in any organism. We find that miR-124 is expressed in many sensory neurons in Caenorhabditis elegans and onset of expression coincides with neuronal morphogenesis. We analyzed the transcriptome of miR-124 expressing and nonexpressing cells from wild-type and mir-124 mutants. We observe that many targets are co-expressed with and actively repressed by miR-124. These targets are expressed at reduced relative levels in sensory neurons compared to the rest of the animal. Our data from mir-124 mutant animals show that this effect is due to a large extent to the activity of miR-124. Genes with nonconserved target sites show reduced absolute expression levels in sensory neurons. In contrast, absolute expression levels of genes with conserved sites are comparable to control genes, suggesting a tuning function for many of these targets. We conclude that miR-124 contributes to defining cell-type-specific gene activity by repressing a diverse set of co-expressed genes.
Clark
Alejandra M
AM
Wellcome Trust Cancer Research UK Gurdon Institute, University of Cambridge, The Henry Wellcome Building of Cancer and Developmental Biology, Tennis Court Rd, Cambridge CB2 1QN, UK.
Goldstein
Leonard D
LD
Tevlin
Maya
M
Tavaré
Simon
S
Shaham
Shai
S
Miska
Eric A
EA
D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D017353:Gene Deletion; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009420:Nervous System / Q000166:cytology / Q000196:embryology / Q000254:growth & development; D011984:Sensory Receptor Cells / Q000378:metabolism*
D035683:MicroRNAs