Evidence for diversifying selection in Potato virus Y and in the coat protein of other potyviruses.
The modes of evolution of the proteins of Potato virus Y were investigated with a maximum-likelihood method based on estimation of the ratio between non-synonymous and synonymous substitution rates. Evidence for diversifying selection was obtained for the 6K2 protein (one amino acid position) and coat protein (24 amino acid positions). Amino acid sites in the coat proteins of other potyviruses (Bean yellow mosaic virus, Yam mosaic virus) were also found to be under diversifying selection. Most of the sites belonged to the N-terminal domain, which is exposed to the exterior of the virion particle. Several of these amino acid positions in the coat proteins were shared between some of these three potyviruses. Identification of diversifying selection events in these different proteins will help to unravel their biological functions and is essential to an understanding of the evolutionary constraints exerted on the potyvirus genome. The hypothesis of a link between evolutionary constraints due to host plants and occurrence of diversifying selection is discussed.
Moury
Benoît
B
Danish Institute of Agricultural Sciences, Biotechnology Group, Thorvaldsensvej 40 1, DK-1871 Frederiksberg C, Denmark2.|Station de Pathologie Végétale, Institut National de la Recherche Agronomique, F-84143 Montfavet cedex, France1.
Morel
Caroline
C
Station de Pathologie Végétale, Institut National de la Recherche Agronomique, F-84143 Montfavet cedex, France1.
Johansen
Elisabeth
E
Danish Institute of Agricultural Sciences, Biotechnology Group, Thorvaldsensvej 40 1, DK-1871 Frederiksberg C, Denmark2.
Jacquemond
Mireille
M
Station de Pathologie Végétale, Institut National de la Recherche Agronomique, F-84143 Montfavet cedex, France1.
D000595:Amino Acid Sequence; D001483:Base Sequence; D002213:Capsid / Q000235:genetics*; D036022:Capsid Proteins; D004279:DNA, Viral; D019143:Evolution, Molecular; D014644:Genetic Variation; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010802:Phylogeny; D019176:Potyviridae / Q000145:classification / Q000235:genetics*; D017800:Potyvirus / Q000235:genetics*; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA
D036022:Capsid Proteins; D004279:DNA, Viral; C090960:coat protein, Potato virus Y