Many microRNA (miRNA)-guided Argonaute proteins can cleave RNA ('slicing'), even though miRNA-mediated target repression is generally cleavage-independent. Here we use Caenorhabditis elegans to examine the role of catalytic residues of miRNA Argonautes in organismal development. In contrast to previous work, mutations in presumed catalytic residues did not interfere with development when introduced by CRISPR.
View Article and Find Full Text PDFSemin Cell Dev Biol
February 2024
MicroRNAs (miRNAs) were first discovered in C. elegans as essential post-transcriptional regulators of gene expression. Since their initial discovery, miRNAs have been implicated in numerous areas of physiology and disease in all animals examined.
View Article and Find Full Text PDFMany Argonaute proteins can cleave RNA ("slicing") as part of the microRNA-induced silencing complex (miRISC), even though miRNA-mediated target repression is generally independent of target cleavage. Here we use genome editing in to examine the role of miRNA-guided slicing in organismal development. In contrast to previous work, slicing-inactivating mutations did not interfere with normal development when introduced by CRISPR.
View Article and Find Full Text PDFMicroRNAs (miRNAs) are known to modulate gene expression, but their activity at the tissue-specific level remains largely uncharacterized. To study their contribution to tissue-specific gene expression, we developed novel tools to profile putative miRNA targets in the intestine and body muscle. We validated many previously described interactions and identified ∼3500 novel targets.
View Article and Find Full Text PDFMicroRNAs (miRNAs) regulate gene output by targeting degenerate elements in mRNAs and have undergone drastic expansions in higher metazoan genomes. The evolutionary advantage of maintaining copies of highly similar miRNAs is not well understood, nor is it clear what unique functions, if any, miRNA family members possess. Here, we study evolutionary patterns of metazoan miRNAs, focusing on the targeting preferences of the let-7 and miR-10 families.
View Article and Find Full Text PDFBackground: 3'untranslated regions (3'UTRs) are poorly understood portions of eukaryotic mRNAs essential for post-transcriptional gene regulation. Sequence elements in 3'UTRs can be target sites for regulatory molecules such as RNA binding proteins and microRNAs (miRNAs), and these interactions can exert significant control on gene networks. However, many such interactions remain uncharacterized due to a lack of high-throughput (HT) tools to study 3'UTR biology.
View Article and Find Full Text PDFChronic myelogenous leukemia (CML) is a myeloproliferative neoplasm that is frequently characterized by the constitutive expression of the oncogenic protein BCR-ABL tyrosine kinase. Tyrosine kinase inhibitors (TKIs) targeting breakpoint cluster region-ABL are the first-line therapy for most CML patients and have drastically improved the prognosis of CML. However, some CML patients are unresponsive to TKI treatment, and a notable proportion of initially responsive patients develop drug resistance.
View Article and Find Full Text PDFLuminescent Identification of Functional Elements in 3'UTRs (3'LIFE) allows the rapid identification of targets of specific miRNAs within an array of hundreds of queried 3'UTRs. Target identification is based on the dual-luciferase assay, which detects binding at the mRNA level by measuring translational output, giving a functional readout of miRNA targeting. 3'LIFE uses non-proprietary buffers and reagents, and publically available reporter libraries, making genome-wide screens feasible and cost-effective.
View Article and Find Full Text PDFMicroRNAs (miRNAs) are short non-coding RNAs that regulate gene output at the post-transcriptional level by targeting degenerate elements primarily in 3'untranslated regions (3'UTRs) of mRNAs. Individual miRNAs can regulate networks of hundreds of genes, yet for the majority of miRNAs few, if any, targets are known. Misexpression of miRNAs is also a major contributor to cancer progression, thus there is a critical need to validate miRNA targets in high-throughput to understand miRNAs' contribution to tumorigenesis.
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