title: Nucleotide sequences of a Korean isolate of apple stem grooving virus associated with black necrotic leaf spot disease on pear (Pyrus pyrifolia).
abstract: Pear black necrotic leaf spot (PBNLS) is a disease of pears caused by capillovirus-like particles, which can be observed under the electron microscope. The disease was analyzed by Western blot analysis with antisera raised against apple stem grooving virus (ASGV) coat protein. cDNAs covering the entire genome were synthesized by RT-PCR and RACE using RNA isolated from Chenopodium quinoa infected with sap extracted from pear leaves carrying black necrotic spot disease. The complete genome sequence of the putative pear virus, 6497 nucleotides in length excluding the poly (A) tail, was determined and analyzed. It contains two overlapping open reading frames (ORFs). ORF1, spans from nucleotide position 37 to 6354, producing a putative protein of 241 kDa. ORF2, which is in a different reading frame within ORF1, begins at nucleotide 4788 and terminates at 5750, and produces a putative protein of 36 kDa. The 241 kDa protein contains sequences related to the NTP-binding motifs of helicases and RNA-dependent RNA polymerases. The 36-kDa protein contains the consensus sequence GDSG found in the active sites of several cellular and viral serine proteases. Morphological and serological analysis, and sequence comparison between the putative pear virus, ASGV, citrus tatter leaf virus and cherry virus A of the capillovirus suggest that PBNLS may be caused by a Korean isolate of ASGV.
authors.affiliation: Department of Genetic Engineering, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Hyekyung
authors.initials: H
authors.lastname: Shim
authors.forename: Yeonju
authors.initials: Y
authors.lastname: Min
authors.forename: Sungyoul
authors.initials: S
authors.lastname: Hong
authors.forename: Moonsik
authors.initials: M
authors.lastname: Kwon
authors.forename: Daehyun
authors.initials: D
authors.lastname: Kim
authors.forename: Hyunran
authors.initials: H
authors.lastname: Kim
authors.forename: Yongmoon
authors.initials: Y
authors.lastname: Choi
authors.forename: Sukchan
authors.initials: S
authors.lastname: Lee
authors.forename: Jaemyung
authors.initials: J
authors.lastname: Yang
mesh_terms: D001483:Base Sequence; D016679:Genome, Viral; D007723:Korea; D016366:Open Reading Frames; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D010942:Plant Viruses / Q000235:genetics* / Q000302:isolation & purification; D031989:Pyrus / Q000821:virology*