title: A Saccharomyces cerevisiae RNA 5'-triphosphatase related to mRNA capping enzyme.
abstract: The Saccharomyces cerevisiae mRNA capping enzyme consists of two subunits: the RNA 5'-triphosphatase (Cet1) and the mRNA guanylyltransferase (Ceg1). Using computer homology searching, a S. cerevisiae gene was identified that encodes a protein resembling the C-terminal region of Cet1. Accordingly, we designated this gene CTL1 (capping enzyme RNAtriphosphatase-like 1). CTL1 is not essential for cell viability and no genetic or physical interactions with the capping enzyme genes were observed. The protein is found in both the nucleus and cytoplasm. Recombinant Ctl1 protein releases gamma-phosphate from the 5'-end of RNA to produce a diphosphate terminus. The enzyme is specific for polynucleotide RNA in the presence of magnesium, but becomes specific for nucleotide triphosphates in the presence of manganese. Ctl1 is the second member of the yeast RNA triphosphatase family, but is probably involved in an RNA processing event other than mRNA capping.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Rodriguez
authors.forename: T
authors.initials: T
authors.lastname: Takagi
authors.forename: E J
authors.initials: EJ
authors.lastname: Cho
authors.forename: S
authors.initials: S
authors.lastname: Buratowski
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D009713:Nucleotidyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D012315:RNA Caps / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000201:enzymology; D000098556:mRNA Guanylyltransferases
chemical_list: D017931:DNA Primers; D005656:Fungal Proteins; D012315:RNA Caps; D011993:Recombinant Fusion Proteins; D009713:Nucleotidyltransferases; D000098556:mRNA Guanylyltransferases; D017766:Acid Anhydride Hydrolases; C023090:RNA triphosphatase