Project description:Lariat RNAs, generated as by-products of RNA splicing from excised introns, must be removed. RNA debranching enzyme (DBR1) is the core factor responsible for lariat RNA removal. However, the mechanism by which DBR1 debranches lariat RNAs remains unclear. Here, we demonstrate that six ALBA (Acetylation Lowers Binding Affinity) proteins interact with DBR1 to enhance its debranching activity and facilitate DBR1's accessibility to lariat RNAs, thereby promoting lariat RNA turnover. Similar to dbr1, alba mutants exhibit pleiotropic developmental defects and accumulate lariat RNAs. ALBAs bind to lariat RNAs via their C-terminal RGG/RG-rich repeats and assist DBR1 in binding to these RNAs. The N-terminal ALBA domain mediates the interaction with DBR1 and enhances its enzymatic activity. Cold stress induces lariat RNA accumulation by attenuating the ALBA–DBR1 interaction, which in turn reduces the induction of cold-responsive genes by impairing their transcription. Together, these findings uncover that lariat RNA turnover requires ALBA proteins.
Project description:Here we applied a novel approach to isolate nuclei from complex plant tissues (https://doi.org/10.1371/journal.pone.0251149), to dissect the transcriptome profiling of the hybrid poplar (Populus tremula × alba) vegetative shoot apex at single-cell resolution.
Project description:N6-methyladenosine (m6A) 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, the interaction between m6A 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, their mRNA targets overlap, and ALBA4 binding sites are juxtaposed to m6A sites. These binding sites correspond to pyrimidine-rich elements previously found to be important for m6A binding of ECT2. Accordingly, both biological effects of ECT2 and its binding to m6A targets in vivo require ALBA association. Our results introduce the YTHDF-ALBA complex as the functional cytoplasmic m6A-reader in plants and define a molecular foundation for the concept of facilitated m6A reading that increases the potential for combinatorial control of biological m6A effects.
Project description:Illumina technology was used to generate mRNA profiles of Populus tremula x alba 717-1B4 control roots and Laccaria bicolor S238N ectomycorrhiza. Total RNA was extracted, TruSeq mRNA Stranded libraries were constructed and and sequenced (2 x 150 bp Illumina HiSeq3000) at the Genotoul sequencing facilities (Toulouse, France). Raw reads were trimmed for low quality (quality score 0.05), Illumina adapters and sequences shorter than 15 nucleotides and aligned to the Populus trichocarpa v4.1 primary transcripts available at Phytozome (https://phytozome-next.jgi.doe.gov/info/Ptrichocarpa_v4_1l) using CLC Genomics Workbench v24.
Project description:The purpose of this study is to explore the influence of the morpho-physiological of Sinapis alba L in response to cadmium challenge