Abstract
Most plant viruses are vectored by insects and the interactions of virus-plant-vector have important ecological and evolutionary implications. Insect vectors often perform better on virus-infected plants. This indirect mutualism between plant viruses and insect vectors promotes the spread of virus and has significant agronomical effects. However, few studies have investigated how plant viruses manipulate plant defenses and promote vector performance. Begomoviruses are a prominent group of plant viruses in tropical and sub-tropical agro-ecosystems and are transmitted by whiteflies. Working with the whitefly Bemisia tabaci, begomoviruses and tobacco, we revealed that C2 protein of begomoviruses lacking DNA satellites was responsible for the suppression of plant defenses against whitefly vectors. We found that infection of plants by tomato yellow leaf curl virus (TYLCV), one of the most devastating begomoviruses worldwide, promoted the survival and reproduction of whitefly vectors. TYLCV C2 protein suppressed plant defenses by interacting with plant ubiquitin. This interaction compromised the degradation of JAZ1 protein, thus inhibiting jasmonic acid defense and the expression of MYC2-regulated terpene synthase genes. We further demonstrated that function of C2 protein among begomoviruses not associated with satellites is well conserved and ubiquitination is an evolutionarily conserved target of begomoviruses for the suppression of plant resistance to whitefly vectors. Taken together, these results demonstrate that ubiquitination inhibition by begomovirus C2 protein might be a general mechanism in begomovirus, whitefly and plant interactions.
Highlights
Vector-borne viruses and their insect vectors have coevolved complex relationships [1,2,3,4]
These results indicate that tomato yellow leaf curl virus (TYLCV) infection suppresses plant defense and in turn benefits its insect vector whitefly
To investigate how TYLCV infection regulates plant defenses, we monitored the expression of genes related to jasmonic acid (JA) synthesis
Summary
Vector-borne viruses and their insect vectors have coevolved complex relationships [1,2,3,4]. Viruses and their vectors form a competitive relationship because they share the same host plants. Due to the immobility of the host plant, insect vectors play significant roles in the epidemiology of plant viruses [5,6,7,8,9,10]. Plant pathogens have been shown mainly to modify behavior of vectors via their shared host plant to achieve an indirect mutualistic relationship between pathogen and vector [15]. The innermost mechanisms of such mutualisms are largely unknown
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
