title: Functional reconstitution of an archaeal splicing endonuclease in vitro.
abstract: Sulfolobus tokodaii strain 7 is one of archaea whose entire genome has been sequenced. The genome sequence revealed that it possesses two open reading frames (ORFs) that are homologous to endA, a protein responsible for splicing endonuclease activity in archaea. Interestingly, one of these two ORFs lacks a putative catalytic amino acid residue for the nuclease activity. To investigate their functions, the two ORFs were individually expressed in E. coli, partially purified, and tested for their nuclease activities in vitro. Using in vitro transcribed tRNA precursors as substrates, we found that the two ORF products are concurrently required to cleave exon-intron junctions. Our finding implies that the splicing endonuclease of the organism is a multi-subunit complex composed of the two ORF products.
authors.affiliation: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yoshinari
authors.forename: Shinji
authors.initials: S
authors.lastname: Fujita
authors.forename: Ryoji
authors.initials: R
authors.lastname: Masui
authors.forename: Seiki
authors.initials: S
authors.lastname: Kuramitsu
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Yokobori
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kita
authors.forename: Yoh-ichi
authors.initials: Y
authors.lastname: Watanabe
mesh_terms: D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004722:Endoribonucleases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism; D012364:RNA, Transfer, Trp / Q000737:chemistry / Q000378:metabolism; D016944:Sulfolobus / Q000201:enzymology* / Q000235:genetics
chemical_list: D019843:Archaeal Proteins; D012322:RNA Precursors; D012364:RNA, Transfer, Trp; D004722:Endoribonucleases; C051012:splicing endonuclease