Physical structure and genetic organization of the genome of maize streak virus (Kenyan isolate)

Abstract

In the above paper a mistake was made in assigning the virion strand of the MSV-K genome. Copy DNAs of two viral DNA inserts of opposite polarity (ALU 19 and ALU 21) were used to determine the polarity of the virion DNA strand. Copy DNA from ALU 19 hybridized to MSV virion DNA, but the sequence of the virion strand was published in the sense of the complement of the insert in ALU 19. Therefore, the previously published sequence is the sequence of the primer (P) strand and not the virion (V) strand. A consequence of the error was the position of the small primer strand on the NSV genome map. The map position of the primer was determined by best fit of the downstream sequence obtained by extension of the endogenous primer in the presence of dideoxynucleotides. The extension was carried using only a single dideoxynucleotide terminator because the supply of virus and viral DNA, imported from Kenya, was exhausted. However, additional viral DNA (200 ng) was recently obtained and primer extension sequencing was carried using all four dideoxynucleotides (Fig. 1). The position of the small primer (80 b) deduced from the downstream sequence indicates that the primer lies in the terminal intergenic region with its 5′-end juxtaposed to the terminus of ORF Vlb (Fig. 1 and 2). My attention was called to this error by the subsequent papers of Mullineaux et al (1), and Donson et al (2) on the sequence of the MSV-N genome. I thank the authors for sharing their prepublished information with me.