Role of PML nuclear bodies during mouse polyomavirus infection: PML protein isoforms and the non-canonical histone H3.3

Abstract

The possible restriction function of promyelocytic nuclear bodies (PML NBs) and their associated proteins in polyomavirus infection was studied. At first, We found that the absence of PML protein positively affects the viral early transcription, however, we found that PML isoform 2 does not play role in the restriction. The role of other isoforms is being studied. At second we followed the possible participation of proteins transiently interacting with PML NBs, chaperones HIRA and DAXX/ATRX, in the deposition of non-canonical histone H3.3 into viral minichromosomes and the functional consequences of such incorporation. Our preliminary results show that H3.3 is incorporated not only in condensed minichromosomes in virions but also accumulated at the sites of MPyV replication. DAXX was shown to be dispensable for the deposition of H3.3 in the genomes.