title: LAMMER kinase Kic1 is involved in pre-mRNA processing.
abstract: The LAMMER kinases are conserved through evolution. They play vital roles in cell growth/differentiation, development, and metabolism. One of the best known functions of the kinases in animal cells is the regulation of pre-mRNA splicing. Kic1 is the LAMMER kinase in fission yeast Schizosaccharomyces pombe. Despite the reported pleiotropic effects of kic1+ deletion/overexpression on various cellular processes the involvement of Kic1 in splicing remains elusive. In this study, we demonstrate for the first time that Kic1 not only is required for efficient splicing but also affects mRNA export, providing evidence for the conserved roles of LAMMER kinases in the unicellular context of fission yeast. Consistent with the hypothesis of its direct participation in multiple steps of pre-mRNA processing, Kic1 is predominantly present in the nucleus during interphase. In addition, the kinase activity of Kic1 plays a role in modulating its own cellular partitioning. Interestingly, Kic1 expression oscillates in a cell cycle-dependent manner and the peak level coincides with mitosis and cytokinesis, revealing a potential mechanism for controlling the kinase activity during the cell cycle. The novel information about the in vivo functions and regulation of Kic1 offers insights into the conserved biological roles fundamental to LAMMER kinases in eukaryotes.
authors: W.M. Keck Science Center, The Claremont Colleges, 925 North Mills Avenue, Claremont, CA 91711, USA. ztang@jsd.claremont.edu
authors: Zhaohua
authors: Z
authors: Tang
authors: Maria
authors: M
authors: Luca
authors: Jessica
authors: J
authors: Portillio
authors: Benson
authors: B
authors: Ngo
authors: Cathey
authors: C
authors: Chang
authors: Teresa
authors: T
authors: Wen
authors: Johanne
authors: J
authors: Murray
authors: Antony
authors: A
authors: Carr
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000502:physiology; D019943:Amino Acid Substitution / Q000502:physiology; D055162:Biocatalysis; D016203:CDC2 Protein Kinase / Q000378:metabolism; D002453:Cell Cycle / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D003593:Cytoplasm / Q000378:metabolism; D017353:Gene Deletion; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000502:physiology; D010957:Plasmids / Q000235:genetics; D011061:Poly A / Q000032:analysis; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D012322:RNA Precursors / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology*; D012326:RNA Splicing / Q000502:physiology; D034443:RNA Transport / Q000502:physiology; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D014170:Transformation, Genetic
chemical_list: D012322:RNA Precursors; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; C400810:ura4 protein, S pombe; D049452:Green Fluorescent Proteins; D011061:Poly A; D011494:Protein Kinases; C403617:Dsk1 protein kinase; C446922:lkh1 protein, S pombe; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; C469447:cdc2 protein, S pombe