Open AccessIdentification of new Potato virus Y (PVY) molecular determinants for the induction of vein necrosis in tobacco
Author(s) -
FAUREZ FLORENCE,
BALDWIN THOMAS,
TRIBODET MICHEL,
JACQUOT EMMANUEL
Publication year - 2012
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/j.1364-3703.2012.00803.x
Subject(s) - biology , tobacco etch virus , potato virus y , virology , mutant , protease , genome , virus , potyvirus , plant virus , genetics , gene , enzyme , biochemistry
SUMMARY Two tobacco vein necrosis (TVN) determinants, the residues K 400 and E 419 , have been identified previously in the helper component‐protease (HC‐Pro) protein sequence of Potato virus Y (PVY). However, since their description, non‐necrotic PVY isolates with both K 400 and E 419 necrotic determinants have been reported in the literature. This suggests the presence in the viral genome of other, as yet uncharacterized, TVN determinant(s). The identification of PVY N pathogenicity determinants was approached through the replacement of genomic regions of the necrotic PVY N ‐605 infectious clone by corresponding sequences from the non‐necrotic PVY O ‐139 isolate. Series of PVY N/O chimeras and site‐directed PVY mutants were constructed to test the involvement of different parts of the PVY genome (from nucleotide 421 to nucleotide 9629) in the induction of TVN symptoms. The analysis of both the genomic characteristics and biological properties of these mutants made it possible to highlight the involvement, in addition to residues K 400 and E 419 , of the residue N 339 of the HC‐Pro protein and two regions in the cytoplasmic inclusion (CI) protein to nuclear inclusion protein a‐protease (NIa‐Pro) sequence (nucleotides 5496–5932 and 6233–6444) in the induction of vein necrosis in tobacco infected by PVY isolates.