Unravelling the nuclear manipulation by geminiviruses

• Applicant: Dr. Björn Krenz
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 431491879

Geminiviruses constitute a large and economically important group of single-stranded (ss) DNA plant viruses with circular genomes, causal agents of devastating crop diseases worldwide. Geminiviral replication occurs in the nucleus and uses the plant DNA replication machinery; the geminiviral genome forms minichromosomes and is subjected to epigenetic modifications, which seem to play an important role in the outcome of geminivirus-plant interactions; viral encapsidation also takes place in the nucleus. It is obvious that the nucleus is the most important subcellular compartment for geminiviral invasion; spatial information regarding the subnuclear distribution of virus-related processes, however, is lacking. Interestingly, geminiviral infection and/or expression of specific viral proteins induce characteristic changes in nuclear architecture, e.g. upon combined expression of Abutilon mosaic virus transport proteins, MP and NSP, inner nuclear envelope-derived vesicles invaginate into nuclei, but also appear associated with the nuclear surface. Additionally, changes in the localization of nuclear markers in geminivirus-infected cells also reflect an alteration of nuclear organization. These observations suggest that a concerted action of plant viral replication and shuttling/movement proteins leads to the re-organization of nuclear and membrane domains, which might be essential for viral replication, evasion of plant anti-viral mechanisms, and trafficking. Thus, the objectives of this proposal are i) to gain insight into the nuclear reorganization and manipulation by geminiviruses; ii) to define the nuclear interactome of geminiviruses; and iii) to identify nuclear targets of viral manipulation. Nuclear import, subversion, and export are essential for the establishment of the viral infection; a deep understanding of how these processes occur would pave the way for the design of efficient anti-viral strategies. Because strategies aimed at impairing the viral co-option of the nucleus would potentially impact viral replication, they would minimize the appearance of potential mutated viral versions, hence providing durable resistance.

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: National Natural Science Foundation of China
• Cooperation Partner: Professorin Rosa Lozano-Durán, Ph.D.