The nucleotide sequence of maize streak virus DNA.

Abstract

The nucleotide sequence of the DNA of maize streak virus (MSV) has been determined. The data were accommodated into one DNA circle of 2687 nucleotides, in contrast to previously characterised geminiviruses which have been shown to possess two circles of DNA. Comparison of the nucleotide sequences of the DNA of MSV with those of cassava latent virus (CLV) and tomato golden mosaic virus (TGMV) showed no detectable homology. Analysis of open reading frames revealed seven potential coding regions for proteins of mol. wt. greater than or equal to 10 000, three in the viral (+) sense and four in the complementary (‐) sense. The position of likely transcription signals on the MSV DNA sequence would suggest a bidirectional strategy of transcription as proposed for CLV and TGMV. Nine inverted repeat sequences which have a potential of forming hairpin structures of delta G greater than or equal to ‐14 kcal/mol have been detected. Three of these hairpin structures are in non‐coding regions and could be involved in the regulation of transcription and/or replication.

Bidirectional transcription of maize streak virus DNA and identification of the coat protein gene

“…The hybridisation of virus-specific transcripts to both senses of MSV DNA was consistent with bi-directional transcription predicted by sequence analysis of MSV DNA (6,7) and other geminiviruses (3)(4)(5). Five transcripts have been mapped to either the viral or complementary senses of CLV DNA (8).…”

“…Golden Cross Bantam, following transmission by the leafhopper Cicadulina mbila (Naud6). Recombinant DNA clones of MSV were prepared from MSV supercoiled dsDNA isolated from infected plants and MSV dsDNA synthesised in vitro from virion ssDNA (6). Clones containing full-length MSV DNA in the vector M13mp9 (9) were used for the mapping experiments: These were pMSV13 and 14, (virus 1+] and complementary [-] sense orientations respectively, of EcoR5-cut MSV DNA inserted into the Smal site); pMSV31 and 32 (+ and -sense BamHl clones of MSV DNA inserted at the BamHl site); pMSV35 (+ sense, a Xhol clone inserted at the Sall site); and pMSV36 and 37 (+ and -sense Smal clones inserted at the Smal site).…”

“…Threonine and serine values were corrected for hydrolytic loss (30 given for those regions with a coding capacity of MW > 10,000 (6). The positions of potential promoters conforming to the core (6) consensus sequence TATA and polyadenylation signals AATAA are also shown.…”

“…The nucleotide sequence determined in our laboratory for a maize isolate of MSV from Nigeria (6), revealed seven open reading frames (ORFs) each with a potential of coding for a protein of MW > 10,000; three in the viral (+) sense and four in the complementary (-) sense. A similar picture has been determined for another maize isolate of MSV from Kenya (7).…”

Lethal Mutations Within the Conserved Stem-loop of African Cassava Mosaic Virus DNA are Rapidly Corrected by Genomic Recombination

“…However, in view of their overall similarities, it is likely that the CFDV and BBTV motifs play the same role as their geminivirus counterparts but have become adapted for specific interactions with virus-and/or host-encoded proteins. In comparison, all naturally occurring monocot-infecting geminiviruses characterized to date have retained the conserved TAATATTAC motif (Mullineaux et al, 1984;MacDowell et al, 1985;Donson et al, 1987;Andersen et al, 1988 ;Chatani et al, 1991 ;Briddon et al, 1992) and none are known to infect coconut or banana, all having host ranges confined to Gramineae.…”