|ZFIN ID: ZDB-PUB-041213-5|
Your Input Welcome
Thank you for submitting comments. Your input has been emailed to ZFIN curators who may contact you if additional information is required.
Oops. Something went wrong. Please try again later.
Substrate requirements for let-7 function in the developing zebrafish embryo
Kloosterman, W.P., Wienholds, E., Ketting, R.F., and Plasterk, R.H.
|Source:||Nucleic acids research 32(21): 6284-6291 (Journal)|
|Registered Authors:||Kloosterman, Wigard, Plasterk, Ronald H.A., Wienholds, Erno|
|PubMed:||15585662 Full text @ Nucleic Acids Res.|
Kloosterman, W.P., Wienholds, E., Ketting, R.F., and Plasterk, R.H. (2004) Substrate requirements for let-7 function in the developing zebrafish embryo. Nucleic acids research. 32(21):6284-6291.
ABSTRACTMicroRNAs (miRNAs) are involved in the regulation of gene expression at the post-transcriptional level by base pairing to the 3'-UTR (untranslated region) of mRNAs. The let-7 miRNA was first discovered in Caenorhabditis elegans and is evolutionarily conserved. We used zebrafish embryos as a vertebrate in vivo system to study substrate requirements for function of let-7. Injection of a double-stranded let-7 miRNA into the zygotes of zebrafish and frogs causes specific phenotypic defects. Only the antisense strand of the let-7 duplex has biological activity. In addition, co-injected mRNA of gfp fused to the 3'-UTR of a zebrafish lin-41 ortholog (a presumed target of let-7) is silenced by let-7. Point mutant studies revealed that the two let-7 target sites in the lin-41 3'-UTR are both essential and sufficient for silencing. let-7 and mir221 together, but not either of them alone, can silence a construct with one of the let-7 target sites replaced by a target site for mir221, showing that two different miRNAs can provide the required cooperative effect. let-7 target sites can be moved around: they are also functional when positioned in the coding sequence or even in the 5'-UTR of gfp. We took advantage of reporter and phenotypic assays to analyze the activity of all possible point mutant derivatives of let-7 and found that only the 5' region is critical for function of let-7.
- Genes / Markers (1)
ERRATA and NOTESSee note