title: CK1δ and CK1ε are components of human 40S subunit precursors required for cytoplasmic 40S maturation.
abstract: Biogenesis of 40S pre-ribosomal subunits requires many trans-acting factors, among them several protein kinases. In this study, we show that the human casein kinase 1 (CK1) isoforms δ and ε are required for cytoplasmic maturation steps of 40S subunit precursors. We show that both CK1δ and CK1ε isoforms are components of pre-40S subunits, on which they phosphorylate the ribosome biogenesis factors ENP1/BYSL and LTV1. Inhibition or co-depletion of CK1δ and CK1ε results in failure to recycle a series of trans-acting factors including ENP1/BYSL, LTV1, RRP12, DIM2/PNO1, RIO2 and NOB1 from pre-40S particles after nuclear export. Furthermore, co-depletion of CK1δ and CK1ε leads to defects in 18S-E pre-rRNA processing. Together, these data demonstrate that CK1δ and CK1ε play a decisive role in triggering late steps of pre-40S maturation that are required for acquisition of functionality of 40S ribosomal subunits in protein translation.
authors.affiliation: Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland.
authors.forename: Ivo
authors.initials: I
authors.lastname: Zemp
authors.forename: Franziska
authors.initials: F
authors.lastname: Wandrey
authors.forename: Sanjana
authors.initials: S
authors.lastname: Rao
authors.forename: Caroline
authors.initials: C
authors.lastname: Ashiono
authors.forename: Emanuel
authors.initials: E
authors.lastname: Wyler
authors.forename: Christian
authors.initials: C
authors.lastname: Montellese
authors.forename: Ulrike
authors.initials: U
authors.lastname: Kutay
mesh_terms: D048149:Casein Kinase 1 epsilon / Q000378:metabolism*; D048148:Casein Kinase Idelta / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D010766:Phosphorylation; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D021122:Protein Subunits / Q000378:metabolism*; D021381:Protein Transport; D012335:RNA, Ribosomal / Q000378:metabolism; D054682:Ribosome Subunits, Small, Eukaryotic / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism
chemical_list: C112245:BYSL protein, human; D015815:Cell Adhesion Molecules; D011498:Protein Precursors; D021122:Protein Subunits; D012335:RNA, Ribosomal; D015534:Trans-Activators; D048149:Casein Kinase 1 epsilon; D048148:Casein Kinase Idelta
keywords: CK1δ; CK1ε; Pre-40S maturation; Protein kinase; Ribosome biogenesis