Roquin is an E3 ubiquitin ligase with a poorly understood but essential role in preventing T-cell-mediated autoimmune disease and in microRNA-mediated repression of inducible costimulator (Icos) mRNA. Roquin and its mammalian paralogue membrane-associated nucleic acid binding protein (MNAB) define a protein family distinguished by an approximately 200 amino acid domain of unknown function, ROQ, that is highly conserved from mammals to invertebrates and is flanked by a RING-1 zinc finger and a CCCH zinc finger. Here we show that human, Drosophila and Caenorhabditis elegans Roquin and human MNAB localize to the cytoplasm and upon stress are concentrated in stress granules, where stalled mRNA translation complexes are stored. The ROQ domain is necessary and sufficient for localization to arsenite-induced stress granules and to induce these structures upon overexpression, and is required to trigger Icos mRNA decay. Gel-shift, SPR and footprinting studies show that an N-terminal fragment centred on the ROQ domain binds RNA from the Icos 3'-untranslated region comprising the minimal sequence for Roquin-mediated repression, adjacent to the miR-101 sequence complementarity. These findings identify Roquin as an RNA-binding protein and establish a specific function for the ROQ protein domain in mRNA homeostasis. Structured digital abstract * MINT-7711163: TIA-1 (uniprotkb:P31483) and Roquin (uniprotkb:Q4VGL6) colocalize (MI:0403) by fluorescence microscopy (MI:0416) * MINT-7711475: RLE-1 (uniprotkb:O45962) and TIA-1 (uniprotkb:P31483) colocalize (MI:0403) by fluorescence microscopy (MI:0416) * MINT-7711487: DmRoquin (uniprotkb:Q9VV48) and TIA-1 (uniprotkb:P31483) colocalize (MI:0403) by fluorescence microscopy (MI:0416) * MINT-7711447, MINT-7711460: MNAB (uniprotkb:Q9HBD1) and TIA-1 (uniprotkb:P31483) colocalize (MI:0403) by fluorescence microscopy (MI:0416) * MINT-7711176: eIF3 (uniprotkb:P55884) and Roquin (uniprotkb:Q4VGL6) colocalize (MI:0403) by fluorescence microscopy (MI:0416) * MINT-7711192: DCP1A (uniprotkb:Q9NPI6) and TIA-1 (uniprotkb:P31483) colocalize (MI:0403) by fluorescence microscopy (MI:0416).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1742-4658.2010.07628.x | DOI Listing |
Osteoarthritis, a major global cause of pain and disability, is driven by the irreversible degradation of hyaline cartilage in joints. Cartilage tissue engineering presents a promising therapeutic avenue, but success hinges on replicating the native physiological environment to guide cellular behavior and generate tissue constructs that mimic natural cartilage. Although electrical stimulation has been shown to enhance chondrogenesis and extracellular matrix production in 2D cultures, the mechanisms underlying these effects remain poorly understood, particularly in 3D models.
View Article and Find Full Text PDFBeilstein J Nanotechnol
December 2024
Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung (ITB), Bandung 40132, Indonesia.
Endosomal entrapment significantly limits the efficacy of drug delivery systems. This study investigates sodium oleate-modified liposomes (SO-Lipo) as an innovative strategy to enhance endosomal escape and improve cytosolic delivery in 4T1 triple-negative breast cancer cells. We aimed to elucidate the mechanistic role of sodium oleate in promoting endosomal escape and compared the performance of SO-Lipo with unmodified liposomes (Unmodified-Lipo) and Aurein 1.
View Article and Find Full Text PDFThe transmembrane protein Synapse Differentiation Induced Gene 4 (SynDIG4) functions as an auxiliary factor of AMPA receptors (AMPARs) and plays a critical role in excitatory synapse plasticity as well as hippocampal-dependent learning and memory. Mice lacking SynDIG4 have reduced surface expression of GluA1 and GluA2 and are impaired in single tetanus-induced long-term potentiation and NMDA receptor (NMDAR)-dependent long-term depression. These findings suggest that SynDIG4 may play an important role in regulating AMPAR distribution through intracellular trafficking mechanisms; however, the precise roles by which SynDIG4 governs AMPAR distribution remain unclear.
View Article and Find Full Text PDFMechanical force orchestrates a myriad of cellular events including inhibition of axon regeneration, by locally activating the mechanosensitive ion channel Piezo enriched at the injured axon tip. However, the cellular mechanics underlying Piezo localization and function remains poorly characterized. We show that the RNA repair/splicing enzyme Rtca acts upstream of Piezo to modulate its expression and transport/targeting to the plasma membrane via Rab10 GTPase, whose expression also relies on Rtca.
View Article and Find Full Text PDFArrhythmogenic cardiomyopathy (ACM) is a genetic form of heart failure that affects 1 in 5000 people globally and is caused by mutations in cardiac desmosomal proteins including , and Individuals with ACM suffer from ventricular arrhythmias, sudden cardiac death, and heart failure. There are few effective treatments and heart transplantation remains the best option for many affected individuals. Here we performed single nucleus RNA sequencing (snRNAseq) and spatial transcriptomics on myocardial samples from patients with ACM and control donors.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!