title: Manipulation of alternative splicing by a newly developed inhibitor of Clks.
abstract: The regulation of splice site usage provides a versatile mechanism for controlling gene expression and for the generation of proteome diversity, playing an essential role in many biological processes. The importance of alternative splicing is further illustrated by the increasing number of human diseases that have been attributed to mis-splicing events. Appropriate spatial and temporal generation of splicing variants demands that alternative splicing be subjected to extensive regulation, similar to transcriptional control. The Clk (Cdc2-like kinase) family has been implicated in splicing control and consists of at least four members. Through extensive screening of a chemical library, we found that a benzothiazole compound, TG003, had a potent inhibitory effect on the activity of Clk1/Sty. TG003 inhibited SF2/ASF-dependent splicing of beta-globin pre-mRNA in vitro by suppression of Clk-mediated phosphorylation. This drug also suppressed serine/arginine-rich protein phosphorylation, dissociation of nuclear speckles, and Clk1/Sty-dependent alternative splicing in mammalian cells. Consistently, administration of TG003 rescued the embryonic defects induced by excessive Clk activity in Xenopus. Thus, TG003, a novel inhibitor of Clk family will be a valuable tool to dissect the regulatory mechanisms involving serine/arginine-rich protein phosphorylation signaling pathways in vivo, and may be applicable for the therapeutic manipulation of abnormal splicing.
authors.affiliation: Laboratory of Gene Expression, School of Biomedical Science, Department of Functional Genomics, Medical Research Institute, Tokyo Medical & Dental University, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Muraki
authors.forename: Bisei
authors.initials: B
authors.lastname: Ohkawara
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Hosoya
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Onogi
authors.forename: Jun
authors.initials: J
authors.lastname: Koizumi
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Koizumi
authors.forename: Kengo
authors.initials: K
authors.lastname: Sumi
authors.forename: Jun-ichiro
authors.initials: J
authors.lastname: Yomoda
authors.forename: Michael V
authors.initials: MV
authors.lastname: Murray
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kimura
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Furuichi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shibuya
authors.forename: Adrian R
authors.initials: AR
authors.lastname: Krainer
authors.forename: Masaaki
authors.initials: M
authors.lastname: Suzuki
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Hagiwara
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001120:Arginine / Q000737:chemistry; D001665:Binding Sites; D019556:COS Cells; D002467:Cell Nucleus / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005914:Globins / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology*; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D015398:Signal Transduction; D013844:Thiazoles / Q000737:chemistry* / Q000494:pharmacology*; D013997:Time Factors; D014981:Xenopus; D014982:Xenopus laevis
chemical_list: D004791:Enzyme Inhibitors; D012333:RNA, Messenger; D011994:Recombinant Proteins; C487497:TG 003; D013844:Thiazoles; D012694:Serine; D005914:Globins; D001120:Arginine; C066780:Clk dual-specificity kinases; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases