Despite a general repression of translation under hypoxia, cells selectively upregulate a set of hypoxia-inducible genes. Results from deep sequencing revealed that Let-7 and miR-103/107 are hypoxia-responsive microRNAs (HRMs) that are strongly induced in vascular endothelial cells. In silico bioinformatics and in vitro validation showed that these HRMs are induced by HIF1α and target argonaute 1 (AGO1), which anchors the microRNA-induced silencing complex (miRISC). HRM targeting of AGO1 resulted in the translational desuppression of VEGF mRNA. Inhibition of HRM or overexpression of AGO1 without the 3' untranslated region decreased hypoxia-induced angiogenesis. Conversely, AGO1 knockdown increased angiogenesis under normoxia in vivo. In addition, data from tumor xenografts and human cancer specimens indicate that AGO1-mediated translational desuppression of VEGF may be associated with tumor angiogenesis and poor prognosis. These findings provide evidence for an angiogenic pathway involving HRMs that target AGO1 and suggest that this pathway may be a suitable target for anti- or proangiogenesis strategies.
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http://dx.doi.org/10.1172/JCI65344 | DOI Listing |
rRNA-derived fragments (rRFs) are a class of emerging post-transcriptional regulators of gene expression likely binding to the transcripts of target genes. However, the lack of knowledge about such targets hinders our understanding of rRF functions or binding mechanisms. The paucity of resources supporting the identification of the targets of rRFs creates a bottleneck in the fast-developing field.
View Article and Find Full Text PDFMol Plant
January 2025
State Key Laboratory of Rice Biology and Breeding, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China. Electronic address:
Herbivore insects deploy salivary effectors to manipulate the defense of their host plants. However, it remains unclear whether small RNAs from insects function as effectors in regulating plant-insect interactions. Here, we report that a microRNA (miR29-b) found in the saliva of phloem-feeding whitefly (Bemisa tabaci) can transfer into the host plant phloem during feeding and fine-tune the defense response of tobacco (Nicotiana tabacum).
View Article and Find Full Text PDFBioelectrochemistry
December 2024
West Guangxi Key Laboratory for Prevention and Treatment of High-incidence Diseases, Youjiang Medical University for Nationalities, Baise, Guangxi 533000, China. Electronic address:
Argonaute 2 (Ago2) is a crucial enzyme in the RNA interference (RNAi) pathway, essential for gene silencing via the cleavage of target messenger RNA (mRNA) mediated by microRNA (miRNA) or small interfering RNA (siRNA). The activity of Ago2 is a significant biomarker for various diseases, including cancer and viral infections, necessitating precise monitoring techniques. Traditional methods for detecting Ago2 activity are often cumbersome and lack the necessary sensitivity and specificity for low-abundance targets in complex samples.
View Article and Find Full Text PDFACS Nano
January 2025
State Key Laboratory of Marine Food Processing and Safety Control, Dalian Polytechnic University, Dalian 116034 Liaoning, China.
Nat Food
January 2025
College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China.
Accurate, sensitive and multiplexed detection of food-borne pathogens is crucial for assessing food safety risks. Here we present a digital DNA-amplification-free nucleic acid detection assay to achieve multiplexed and ultrasensitive detection of three food-borne pathogens. We used mesophilic Clostridium butyricum argonaute and magnetic beads in a digital carrier system (d-MAGIC).
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