ORF 5 of grapevine virus A encodes a nucleic acid-binding protein and affects pathogenesis.
A previous functional analysis of the genome of grapevine virus A (GVA) was not conclusive as to the role of open reading frame 5 (ORF 5). This ORF encodes a 10-kDa protein (p10) carrying two distinct domains: a basic, arginine-rich domain and a zinc-finger domain. P10 was cloned and expressed in Escherichia coli, and was shown by northwestern assays to interact with nucleic acids. In-frame deletion of the basic region abolished P10's nucleic acid-binding capability, whereas substitution of cysteine residues by serine in the zinc-finger domain did not affect binding. These mutations were inserted into the full-length infectious clone. It has been shown that ORF 5 mutations do not affect replication of GVA-RNA. However, plants inoculated with the aforementioned mutations did not develop symptoms, and Western blot analysis revealed markedly reduced expression of the movement protein (the product of ORF 3).
Galiakparov
Nurbol
N
Agricultural Research Organization, The Volcani Center, Department of Virology, Tolkovski Laboratory, Bet Dagan 50250, Israel.
Tanne
Edna
E
Mawassi
Munir
M
Gafny
Rony
R
Sela
Ilan
I
D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics; D016679:Genome, Viral; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016366:Open Reading Frames; D010942:Plant Viruses / Q000235:genetics* / Q000472:pathogenicity*; D017434:Protein Structure, Tertiary; D012328:RNA Viruses / Q000235:genetics* / Q000472:pathogenicity*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000821:virology; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology
D002352:Carrier Proteins; D004279:DNA, Viral; D011994:Recombinant Proteins; D014764:Viral Proteins