Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2007
Publication Date: 8/1/2007
Citation: Thekke Veetil, T., Domier, L.L. 2007. Sequence diversity of read through protein of Midwestern isolates of Soybean dwarf virus [abstract]. Phytopathology. 97(7):S114.
Technical Abstract: Soybean dwarf virus (SbDV) is a single-stranded positive-sense RNA virus first identified in cultivated soybean (Glycine max L.) in Japan. The virus has been reported to cause significant yield losses, up to 40 percent in Northern Japan. Like other members of the Luteoviridae, SbDV is phloem limited and aphid transmitted in a persistent, circulative and nonpropagative manner. The readthrough protein (RTP), a minor component of viral capsids, is composed of the coat protein (CP) with a c-terminal extension called the readthrough domain (RTD), which is believed to have a significant role in aphid transmission of luteoviruses. This study was conducted to analyze the amino acid sequence diversity of CP and RTD of clover and soybean isolates collected from two Midwestern states, Illinois and Wisconsin. Total RNA was extracted and reverse transcribed to first strand cDNA. The region encoding RTP was amplified and sequenced. Analysis of predicted amino acids of 16 SbDV isolates revealed that the CP region was conserved, and that the RTD was more diverse. A total of 33 amino acid changes were observed in the RTD of the 16 isolates compared to two in CP sequences. Nucleotide sequence identity ranged from 95 to 99%. Phylogenetic analysis of both amino acid and nucleotide sequences showed two distinct clusters of SbDV isolates.