title: Photoreactivities of 5-bromouracil-containing RNAs.
abstract: 5-Bromouracil ((Br)U) was incorporated into three types of synthetic RNA and the products of the photoirradiated (Br)U-containing RNAs were investigated using HPLC and MS analysis. The photoirradiation of r(GCA(Br)UGC)(2) and r(CGAA(Br)UUGC)/r(GCAAUUCG) in A-form RNA produced the corresponding 2'-keto adenosine ((keto)A) product at the 5'-neighboring nucleotide, such as r(GC(keto)AUGC) and r(CGA(keto)AUUGC), respectively. The photoirradiation of r(CGCG(Br)UGCG)/r(C(m)GCAC(m)GCG) in Z-form RNA produced the 2'-keto guanosine ((keto)G) product r(CGC(keto)GUGCG), whereas almost no products were observed from the photoirradiation of r(CGCG(Br)UGCG)/r(C(m)GCAC(m)GCG) in A-form RNA. The present results indicate clearly that hydrogen (H) abstraction by the photochemically generated uracil-5-yl radical selectively occurs at the C2' position to provide a 2'-keto RNA product.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8501, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Morinaga
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Kizaki
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Takenaka
authors.forename: Shuhei
authors.initials: S
authors.lastname: Kanesato
authors.forename: Yuta
authors.initials: Y
authors.lastname: Sannohe
authors.forename: Ryu
authors.initials: R
authors.lastname: Tashiro
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sugiyama
mesh_terms: D001976:Bromouracil / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D008027:Light; D012313:RNA / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D001976:Bromouracil; D012313:RNA