ARGONAUTE (AGO) proteins bind to small non-coding RNAs to form RNA-induced silencing complexes. In the RNA-bound state, AGO is stable while RNA-free AGO turns over rapidly. Molecular features unique to RNA-free AGO that allow its specific recognition and degradation remain unknown.
View Article and Find Full Text PDFN6-methyladenosine (mA) exerts many of its regulatory effects on eukaryotic mRNAs by recruiting cytoplasmic YT521-B homology-domain family (YTHDF) proteins. Here, we show that in Arabidopsis thaliana, the interaction between mA and the major YTHDF protein ECT2 also involves the mRNA-binding ALBA protein family. ALBA and YTHDF proteins physically associate via a deeply conserved short linear motif in the intrinsically disordered region of YTHDF proteins and their mRNA target sets overlap, with ALBA4 binding sites being juxtaposed to mA sites.
View Article and Find Full Text PDFPlants use mRNA methylation to regulate gene expression. As in other eukaryotes, the only abundant methylated nucleotide in plant mRNA bodies is N6-methyladenosine (mA). The conserved core components of mA-based genetic control are a multi-subunit nuclear methyltransferase, and a set of nuclear and cytoplasmic RNA-binding proteins consisting of an mA recognition module, the YT521-B homology (YTH) domain, and long intrinsically disordered regions (IDRs).
View Article and Find Full Text PDFThe unfolded protein response (UPR) maintains proteostasis upon endoplasmic reticulum (ER) stress, and is initiated by a range of physiological and pathological processes. While there have been advances in developing fluorescent reporters for monitoring individual signaling pathways of the UPR, this approach may not capture a cell's overall UPR activity. Here we describe a novel sensor of UPR activity, sUPRa, which is designed to report the global UPR.
View Article and Find Full Text PDFFlowering plant genomes encode four or five DICER-LIKE (DCL) enzymes that produce small interfering RNAs (siRNAs) and microRNAs, which function in RNA interference (RNAi). Different RNAi pathways in plants effect transposon silencing, antiviral defense, and endogenous gene regulation. DCL2 acts genetically redundantly with DCL4 to confer basal antiviral defense.
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