Rotaviruses is the most common cause of diarrheal disease in infants and children. It kills
hundreds of thousands of infants each year. Although current vaccines are
effective in preventing aggravation of rotaviruses, the development of
more effective vaccines at lower cost is expected.
study well how rotaviruses invade and replicate in a cell. To identify
which genes are crucial for the infection of rotaviruses, scientists at
the Research Institute for Microbial Diseases at Osaka University report
a new plasmid-based reverse genetics system.
‘To identify which genes are crucial for the infection of rotaviruses, scientists have developed a new plasmid-based reverse genetics system.’
The study can be read in Proceedings of the National Academy of Sciences
of the United States of America.
"Reverse genetics allows us to generate artificially engineered
viruses", says Associate Professor Takeshi Kobayashi, who led the study.
"Using reverse genetics, we can mutate a gene and see its effects on
the virus," he added.
Reverse genetics systems have been developed for a wide number of
viruses to study the conditions in which a virus thrives, but systems
for multiple-segmented RNA-based viruses like rotaviruses have proven
more difficult. Kobayashi's group solved this problem by including two
viral proteins, FAST and VV capping enzyme, into their plasmid-based
system. Taking advantage, the researchers tested their system by
mutating a single protein of rotaviruses, NSP1, finding that they could
decrease viral replication.
Through comprehensive testing of all proteins in future studies,
Kobayashi expects to find the key determinants that make rotaviruses a
severe pubic threat. "We could modify the propagation and pathogenicity
of the rotavirus", he said.
Kobayashi is optimistic about how plasmid-based reverse genetics
system will bring new innovations to combat rotaviruses. "Because no one
could synthesize rotaviruses artificially, less is known about the
replication and pathogenesis." He expects the system will increase the
number of labs working on rotaviruses and lead to more effective