Scientists have identified that a tiny protein, known to play a major role in the replication of foot-and-mouth disease virus (FMDV), also helps the virus increase the efficiency with which it can pack information into its genome. FMD is an animal pathogen of great economic importance and understanding how the virus replicates could lead to the development of more effective vaccines against the disease in the future.
FMD has a small amount of genetic material and has consequently evolved ways to multiply the functions available from a small genome, increasing what is known as their “genetic economy”. During replication, the FMD virus creates a string of proteins, known as a polyprotein, which are subsequently cut up in to their individual proteins.
Researchers at The Pirbright Institute and the University of Leeds, found that a tiny protein known as 3B3 is key in directing the processing of the P3 polyprotein, containing a wide range of essential proteins, into its constituent parts. This is in addition to, and independent from, 3B3’s role in helping FMD replicate.
This study, reported in PLOS pathogens, shows how one small protein with multiple functions can control viral replication and demonstrates a new level of genetic economy in the picornaviruses family, to which FMD belongs.
Such methods to increase the functional potential of limited genome sizes extend beyond FMD to other members of the picornavirus family such as poliovirus, as well as non-picornavirus families.
“Sometimes it’s the little things that can make the big differences” says Professor Nicola Stonehouse, lead researcher from the University of Leeds. “By understanding the role of this tiny viral protein in the replication of foot-and-mouth disease virus, we’re hoping to find more effective vaccines that fight the disease.”
Systems like these have the potential to be exploited to produce attenuated vaccines. Researchers are now in the process of investigating how mutations within the polyprotein may be used for producing such vaccines.
This study was funded by the Biotechnology and Biological Sciences Research Council (BBSRC), grant number (BB/K003801/1)