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Further Evidence for Limited Genetic Diversity among East African Isolates of Sweet potato chlorotic stunt virus
Author(s) -
Aritua V.,
Barg E.,
Adipala E.,
Gibson R. W.,
Vetten H. J.
Publication year - 2008
Publication title -
journal of phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 60
eISSN - 1439-0434
pISSN - 0931-1785
DOI - 10.1111/j.1439-0434.2007.01338.x
Subject(s) - biology , virology , genetic diversity , genetics , sociology , population , demography
In Africa, the crinivirus Sweet potato chlorotic stunt virus (SPCSV) exists in two serologically and genetically distinct strains, geographically distinguished as a West African (SPCSV WA ) and an East African (SPCSV EA ) strain. To obtain a better understanding of the genetic diversity among SPCSV EA isolates, the major coat protein (CP) and heat shock protein 70 homologue (Hsp70h) gene sequences of 24 further isolates of SPCSV EA were determined and compared. SPCSV EA diversity was also examined using available monoclonal antibodies (mAbs) to SPCSV EA but there was no apparent coincidence between CP and partial Hsp70h gene nucleotide sequences and the subdivision of SPCSV EA isolates by the mAbs into two serotypes, suggesting this latter may not be of great biological significance. The nucleotide (nt) sequences of isolates of SPCSV EA displayed a high degree of conservation and the only variation observed consisted of a few base exchanges. Pairwise alignments of CP nucleotide sequences revealed differences of <4% between SPCSV EA isolates. Comparisons with published SPCSV sequences confirmed a more distant relationship (up to 34.6% nt; 12% amino acid divergence) between the Hsp70h sequences of isolates of SPCSV EA and SPCSV WA and indicated that SPCSV EA in East and Southern Africa is the more homogeneous than SPCSV WA isolates from West Africa, North and South America, which were up to 12.4% nt divergent among themselves.