Highly compound mutation of mir-51-56 (miR-100) microRNA binding sites is phenotypically silent in C. elegans

ABSTRACT: MicroRNA (miRNA) are small non-coding RNAs that regulate gene expression post-transcriptionally by targeting mRNAs for translational inhibition and degradation. MiRNAs are functionally categorized into families based on nucleotides 2-7 at their 5ʹ ends, known as the “seed” region. Members of a miRNA family are often functionally redundant due to their largely overlapping targets. The mir-51-56/miR-100 family of miRNAs is widely conserved across metazoans, represented by mir-51-56 in C. elegans. The mir-51-56 family is required for embryonic viability, in which the family members function redundantly. To better understand the roles of mir-51-56 in development, we examined mutants in which mir-51-56 dosage is reduced (mir-52; mir-54-56 deletion), allowing bypass of embryonic lethality and characterization of post-embryonic phenotypes. These mutants display developmental delay, reduced brood size, mating defects, and behavior and gene expression changes reflective of caloric restriction. To assess the functional importance of mir-51 family targets in these phenotypes, we queried a list of putative targets using a focused RNAi screen and mRNA-sequencing. Through these efforts, we narrowed down a candidate list of 31 mir-51 family targets, which we investigated for their potential to recapitulate mir-52; mir-54-56 phenotypes upon derepression. To this end, we used CRISPR to mutate the miRNA binding sites in all 31 putative target genes, generating single mutant strains as well as multiple highly compound mutant strains with up to thirteen genes with mutated miRNA binding sites. Surprisingly, single and highly compound binding site mutants were largely wild type and do not recapitulate phenotypes of mir-52; mir-54-56. These results may suggest that the mir-51-56 family loss of functions phenotypes are driven by the simultaneous derepression of a large number of targets and thus technically challenging to effectively model genetically.

ORGANISM(S): Caenorhabditis elegans

PROVIDER: GSE343338 | GEO | 2026/08/16

REPOSITORIES: GEO