In the intricate dance of plant viruses and their hosts, a new partner has been identified that could reshape our understanding of viral spread and potentially open doors to innovative control strategies. Researchers, led by Myung-Hwi Kim from the Department of Agricultural Biotechnology at Seoul National University, have uncovered a critical interaction between the heat shock protein 90 (HSP90) and VP37, the movement protein of broad bean wilt virus 2 (BBWV2). This discovery, published in the journal mBio, sheds light on the molecular mechanisms underlying viral cell-to-cell movement and could have significant implications for the agriculture and energy sectors.
Plants, much like humans, rely on a complex network of proteins to maintain their health and respond to threats. HSP90, a molecular chaperone, is one such protein that plays a crucial role in helping other proteins fold correctly and function properly. In the context of viral infection, HSP90 has been found to interact with VP37, the movement protein of BBWV2, facilitating the virus’s spread from cell to cell through structures called plasmodesmata.
The study utilized a variety of techniques, including yeast two-hybrid assays, co-immunoprecipitation, and bimolecular fluorescence complementation, to confirm the interaction between HSP90 and VP37. “Our findings suggest that HSP90 is not just a passive participant in this process, but an active facilitator,” Kim explains. “It interacts with VP37 specifically at the plasmodesmata, helping to form tubules that allow the virus to move from one cell to another.”
To further validate their findings, the researchers employed virus-induced gene silencing and chemical inhibition. By silencing HSP90 or inhibiting its function with geldanamycin, they were able to significantly reduce the systemic spread of BBWV2 in Nicotiana benthamiana plants. “This inhibition of HSP90 function disrupts the interaction with VP37 and prevents the formation of the tubules needed for viral movement,” Kim elaborates.
The implications of this research extend beyond the realm of plant virology. Understanding how viruses exploit host proteins to spread could lead to the development of novel antiviral strategies. For the energy sector, which relies heavily on agricultural crops for biofuels, this research could pave the way for more resilient and productive crops. By targeting HSP90 or other host proteins involved in viral movement, it may be possible to develop crops that are less susceptible to viral infections, thereby increasing yield and reducing the need for chemical interventions.
Moreover, this study highlights the importance of HSP90 in viral infection, suggesting that the chaperone activity of HSP90 may function in changing the conformational structure of VP37, thereby facilitating the assembly and function of virus-induced structures required for viral cell-to-cell movement. This insight could inspire further research into the role of HSP90 in other viral infections, both in plants and potentially in animals, including humans.
As we continue to unravel the complexities of plant-virus interactions, studies like this one bring us one step closer to a future where viral infections are no longer a significant threat to global food security and energy production. The findings, published in mBio, underscore the importance of fundamental research in driving technological advancements and shaping the future of agriculture and energy.