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bioRxiv · 10.1101/2020.07.20.212167

Plant DNA polymerases alpha and delta mediate replication of geminiviruses

Wu, M.·Wei, H.·Tan, H.·Pan, S.·Liu, Q.·Bejarano, E. R.·Lozano-Duran, R.
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Abstract

Geminiviruses are causal agents of devastating diseases in crops. Geminiviruses have circular single-stranded (ss)DNA genomes that are replicated in the nucleus of the infected plant cell through double-stranded (ds)DNA intermediates by the plants DNA replication machinery; which host DNA polymerase mediates geminiviral multiplication, however, has so far remained elusive. Here, we show that subunits of the nuclear replicative DNA polymerases and {delta} physically interact with the geminivirus-encoded replication enhancer protein, C3, and are required for viral replication. Our results suggest that while DNA polymerase is essential to generate the viral dsDNA intermediate, DNA polymerase {delta} mediates the synthesis of new copies of the geminiviral ssDNA genome, and that the virus-encoded C3 acts selectively recruiting DNA polymerase {delta} over {varepsilon} to favour a productive replication.

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Wu, M., Wei, H., Tan, H., Pan, S., Liu, Q., Bejarano, E. R., Lozano-Duran, R.. 2020-07-21. Plant DNA polymerases alpha and delta mediate replication of geminiviruses. https://doi.org/10.1101/2020.07.20.212167

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