title: SR protein kinases promote splicing of nonconsensus introns.
abstract: Phosphorylation of the spliceosome is essential for RNA splicing, yet how and to what extent kinase signaling affects splicing have not been defined on a genome-wide basis. Using a chemical genetic approach, we show in Schizosaccharomyces pombe that the SR protein kinase Dsk1 is required for efficient splicing of introns with suboptimal splice sites. Systematic substrate mapping in fission yeast and human cells revealed that SRPKs target evolutionarily conserved spliceosomal proteins, including the branchpoint-binding protein Bpb1 (SF1 in humans), by using an RXXSP consensus motif for substrate recognition. Phosphorylation of SF1 increases SF1 binding to introns with nonconsensus splice sites in vitro, and mutation of such sites to consensus relieves the requirement for Dsk1 and phosphorylated Bpb1 in vivo. Modulation of splicing efficiency through kinase signaling pathways may allow tuning of gene expression in response to environmental and developmental cues.
authors.affiliation: Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Jesse J
authors.initials: JJ
authors.lastname: Lipp
authors.affiliation: Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Marvin
authors.affiliation: Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Kevan M
authors.initials: KM
authors.lastname: Shokat
authors.affiliation: Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Guthrie
mesh_terms: D020816:Amino Acid Motifs / Q000235:genetics; D000595:Amino Acid Sequence; D015153:Blotting, Western; D007438:Introns / Q000235:genetics*; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D022821:RNA Splice Sites / Q000187:drug effects; D012326:RNA Splicing; D000072260:RNA Splicing Factors; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017414:Ribonucleoprotein, U4-U6 Small Nuclear / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics* / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D022821:RNA Splice Sites; D000072260:RNA Splicing Factors; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D029702:Schizosaccharomyces pombe Proteins; C403617:Dsk1 protein kinase; D017346:Protein Serine-Threonine Kinases; C489981:prp4 protein, S pombe