AUTHOR=Stewart Lucy R. , Willie Kristen , Xie Wenshuang , Todd Jane , Tran Hong Hanh 

TITLE=First waikavirus infectious clones and vascular expression of green fluorescent protein from maize chlorotic dwarf virus

JOURNAL=Frontiers in Virology

VOLUME=3

YEAR=2023

URL=https://www.frontiersin.org/journals/virology/articles/10.3389/fviro.2023.1216285

DOI=10.3389/fviro.2023.1216285

ISSN=2673-818X

ABSTRACT=<p>Plant viruses classified in the genus <italic>Waikavirus</italic>, family <italic>Secoviridae</italic>, are positive sense single-stranded RNA viruses that include important pathogens of maize (maize chlorotic dwarf virus; MCDV) and rice (rice tungro spherical virus; RTSV). Many aspects of the molecular biology of waikaviruses remain unexplored because of experimental challenges and lack of infectious clones for low titer, phloem-limited, and obligately vector-transmitted waikaviruses. Here we report the first development of waikavirus infectious clones for two MCDV strains, MCDV-S and MCDV-M1, and insect-free launching of infections from these clones in maize by vascular puncture inoculation. We further developed a green fluorescent protein (GFP)-tagged MCDV clone by replacing the viral p27-encoding sequence with GFP-encoding sequence. GFP-tagged virus moved systemically in plants and caused symptomatic infection similar to wild type virus, with vascular expression of GFP. Development of waikavirus infectious clones is a major advance for this group of agriculturally significant viruses.</p>