Substrate requirements for let-7 function in the developing zebrafish embryo. Export

@article{citeulike:1289702, abstract = {MicroRNAs (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.}, address = {The Hubrecht Laboratory, Centre for Biomedical Genetics, 3584 CT Utrecht, The Netherlands.}, author = {Kloosterman, W. P. and Wienholds, E. and Ketting, R. F. and Plasterk, R. H.}, citeulike-article-id = {1289702}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/15585662}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=15585662}, issn = {1362-4962}, journal = {Nucleic Acids Res}, keywords = {5utr, animal, cds, let7, mirna, target}, number = {21}, pages = {6284--6291}, posted-at = {2007-05-11 13:35:10}, priority = {2}, title = {Substrate requirements for let-7 function in the developing zebrafish embryo.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/15585662}, volume = {32}, year = {2004} }

TY - JOUR ID - citeulike:1289702 L3 - citeulike-article-id:1289702 N2 - MicroRNAs (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. IS - 21 JF - Nucleic Acids Res SN - 1362-4962 AD - The Hubrecht Laboratory, Centre for Biomedical Genetics, 3584 CT Utrecht, The Netherlands. EP - 6291 TI - Substrate requirements for let-7 function in the developing zebrafish embryo. VL - 32 SP - 6284 KW - 5utr KW - animal KW - cds KW - let7 KW - mirna KW - target AU - Kloosterman, WP AU - Wienholds, E AU - Ketting, RF AU - Plasterk, RH PY - 2004/// UR - http://view.ncbi.nlm.nih.gov/pubmed/15585662 ER -