The C. elegans microRNA let-7 binds to imperfect let-7 complementary sites from the lin-41 3'UTR.
Caenorhabditis elegans let-7, a founding member of the microRNA family, is predicted to bind to six sites in the 3'UTR of the mRNA of its target gene, lin-41, to down-regulate LIN-41. Here, we demonstrate that wild-type let-7 microRNA binds in vitro to RNA from the lin-41 3'UTR. This interaction is dependent on two conserved let-7 complementary sites (LCSs). A 27-nucleotide sequence between the LCSs is also necessary for down-regulation in vivo. LCS mutations compensatory to the lesion in let-7(n2853) can partially restore lin-41 3'UTR function in a let-7(n2853) background, providing the first experimental evidence for an animal miRNA binding directly to its validated target in vivo.
Vella
Monica C
MC
Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA.
Choi
Eun-Young
EY
Lin
Shin-Yi
SY
Reinert
Kristy
K
Slack
Frank J
FJ
D020413:3' Untranslated Regions; D000818:Animals; D001665:Binding Sites; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation; D005786:Gene Expression Regulation / Q000502:physiology*; D035683:MicroRNAs / Q000378:metabolism*; D009154:Mutation; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics*
D020413:3' Untranslated Regions; D029742:Caenorhabditis elegans Proteins; C410586:LIN-41 protein, C elegans; D035683:MicroRNAs; D014157:Transcription Factors; C474488:let-7 microRNA, C elegans