Project description:Puf3 is a RNA-binding protein, a member of the conserved Puf-protein family. Combining different functional genomics data, we have analyzed the role of Puf3 in post-transcriptional gene regulation in S. pombe. We present data on Puf3 interacting proteins and regulatory mRNA targets.
Project description:In eukaryotic cells, inefficient splicing is surprisingly common and leads to degradation of transcripts with retained introns. How pre-mRNAs are committed to nuclear decay is unknown. Here we uncover a mechanism by which intronic transcripts are targeted for nuclear degradation in fission yeast. Surprisingly, sequence elements within âsuicidalâ introns co-transcriptionally recruit the exosome adaptor Mmi1 not only to degrade unspliced precursor, but also to downregulate levels of the resulting mRNA. Under conditions permissive for fast splicing, Mmi1 is no longer recruited and negative expression regulation is relieved. This mechanism negatively regulates levels of the RNA-helicase DDX5/Dbp2 to ensure cell survival in response to stress. We propose that suicidal introns are maintained because they facilitate regulation of gene expression. We identify multiple novel Mmi1 targets including mRNAs, non-coding RNAs, and sn/snoRNAs. We suggest a general role in RNA regulation for Mmi1 beyond degradation of meiotic transcripts. Two biological replicates of CRAC experiments (Control and Mmi1-HTP). Six RNAseq datasets in total: three biological replicates of wt and delta Mmi1 strain.
Project description:Analysis of splicing defects in Schizosaccharomyces pombe upon chemical genetic inhibition of splicing kinases dsk1, lkh1, and prp4, as well as alanine-mutation of phosphorylated residues in the splicing factors bpb1, prp2, rsd1, srp1, srp2, usp101, usp103, sum3, prp22, cdc5, and cwf22. This study shows the splicing kinase dsk1 modulates splicing efficiency of introns with non-consensus splice sites, likely through phosphorylation of bpb1. Modulation of splicing efficiency of transcripts through kinase signaling pathways may afford the necessary flexibility to tune the gene expression profile in response to environmental and developmental cues. Experiments were conducted as direct two-color designs with 2-3 biological replicates per genotype pairing. Raw microarray data was normalized with loess normalization using the R package limma. Log2-fold changes (perturbation over reference) are reported. Each splicing event on the custom-designed splicing microarray was monitored with an exon probe reading out mRNA changes, an intron probe for unspliced pre-mRNA, and a splice junction probe spanning the junction between two spliced exons. For the analysis of the splicing efficiency for a given intron, a score was calculated as exon*intron/junction.
Project description:Analysis of splicing defects in Schizosaccharomyces pombe upon chemical genetic inhibition of splicing kinases dsk1, lkh1, and prp4, as well as alanine-mutation of phosphorylated residues in the splicing factors bpb1, prp2, rsd1, srp1, srp2, usp101, usp103, sum3, prp22, cdc5, and cwf22. This study shows the splicing kinase dsk1 modulates splicing efficiency of introns with non-consensus splice sites, likely through phosphorylation of bpb1. Modulation of splicing efficiency of transcripts through kinase signaling pathways may afford the necessary flexibility to tune the gene expression profile in response to environmental and developmental cues.
Project description:In eukaryotic cells, inefficient splicing is surprisingly common and leads to degradation of transcripts with retained introns. How pre-mRNAs are committed to nuclear decay is unknown. Here we uncover a mechanism by which intronic transcripts are targeted for nuclear degradation in fission yeast. Surprisingly, sequence elements within “suicidal” introns co-transcriptionally recruit the exosome adaptor Mmi1 not only to degrade unspliced precursor, but also to downregulate levels of the resulting mRNA. Under conditions permissive for fast splicing, Mmi1 is no longer recruited and negative expression regulation is relieved. This mechanism negatively regulates levels of the RNA-helicase DDX5/Dbp2 to ensure cell survival in response to stress. We propose that suicidal introns are maintained because they facilitate regulation of gene expression. We identify multiple novel Mmi1 targets including mRNAs, non-coding RNAs, and sn/snoRNAs. We suggest a general role in RNA regulation for Mmi1 beyond degradation of meiotic transcripts.