A rep-based hairpin inhibits replication of diverse maize streak virus isolates in a transient assay

Autor:	Marion Bezuidenhout, Edward P. Rybicki, Dionne N. Shepherd, Darren P. Martin, Francisco Lakay, Betty E. Owor, Jennifer A. Thomson
Rok vydání:	2011
Předmět:	Transients and Migrants Genetics biology Inverted repeat viruses Virus Replication biology.organism_classification Virology Virus Small hairpin RNA Mastrevirus Geminiviridae Viral replication Maize streak virus RNA Viral Gene silencing Gene Silencing Gene Plant Diseases RNA Double-Stranded
Zdroj:	Journal of General Virology. 92:2458-2465
ISSN:	1465-2099 0022-1317
DOI:	10.1099/vir.0.032862-0
Popis:	Maize streak disease, caused by the A strain of the African endemic geminivirus, maize streak mastrevirus (MSV-A), threatens the food security and livelihoods of subsistence farmers throughout sub-Saharan Africa. Using a well-established transient expression assay, this study investigated the potential of a spliceable-intron hairpin RNA (hpRNA) approach to interfere with MSV replication. Two strategies were explored: (i) an inverted repeat of a 662 bp region of the MSV replication-associated protein gene (rep), which is essential for virus replication and is therefore a good target for post-transcriptional gene silencing; and (ii) an inverted repeat of the viral long intergenic region (LIR), considered for its potential to trigger transcriptional silencing of the viral promoter region. After co-bombardment of cultured maize cells with each construct and an infectious partial dimer of the cognate virus genome (MSV-Kom), followed by viral replicative-form-specific PCR, it was clear that, whilst the hairpin rep construct (pHPrepΔI662) completely inhibited MSV replication, the LIR hairpin construct was ineffective in this regard. In addition, pHPrepΔI662 inhibited or reduced replication of six MSV-A genotypes representing the entire breadth of known MSV-A diversity. Further investigation by real-time PCR revealed that the pHPrepΔI662 inverted repeat was 22-fold more effective at reducing virus replication than a construct containing the sense copy, whilst the antisense copy had no effect on replication when compared with the wild type. This is the first indication that an hpRNA strategy targeting MSV rep has the potential to protect transgenic maize against diverse MSV-A genotypes found throughout sub-Saharan Africa.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d1615800fa226bffbdc3b4f9c5200f30 https://doi.org/10.1099/vir.0.032862-0 Zobrazit plný text záznamu