Structural and Biochemical Characterisation of Bunyavirus L proteins.

• Applicant: Dr. Sophia Reindl
• Subject Area: Structural Biology ; Virology
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 262051160

Bunyaviruses belong to the group of viruses that possess a segmented RNA genome in negative orientation. Many of the newly emerged viral pathogens belong to the family of Bunyaviridae. They are capable of infecting both humans and animals and can cause severe diseases in their hosts. Prominent examples known from the news due to recent outbreaks are Hantaviruses, the Rift-Valley Fever Virus, the Schmallenberg Virus and the Crimean-Congo-Hemorrhagic Fever Virus. A key component in the lifecycle of these viruses is the viral L protein, a large multi-domain protein containing the RNA-dependant RNA polymerase of the virus. Due to its large size and complex structure, data on the L protein is scarce. A thorough understanding of this large molecular machine will provide an important basis for medical research. We therefore aim at studying the purified L protein using a interdisciplinary approach combining classical biochemistry with virology and structural biology. Specific objectives include (1) the recombinant expression and purification of fragments of the Bunyavirus L protein in bacterial cells, (2) the biochemical and structural investigation of these proteins to understand their enzymatic function and determine potential structural homologs. In addition (3) we will purify full-length L protein using insect cell or mammalian cell expression systems for functional analyses. Finally (4) we will use cell based replicon assays to analyse the role of specific residues or regions of the L protein in transcription and replication. Results from one of these objectives will aid in optimization of the experimental design for the other objectives. In summary, all results taken together will provide an integrated view of the role of the L protein in the viral life cycle.

• DFG Programme: Research Grants