(MDPI, 2021) Aguirre Sánchez, Eduardo; Beperet Arive, Inés; Williams, Trevor; Caballero Murillo, Primitivo; Institute for Multidisciplinary Research in Applied Biology - IMAB
The mechanisms generating variability in viruses are diverse. Variability allows baculoviruses
to evolve with their host and with changes in their environment. We examined the role of
one genetic variant of Chrysodeixis includens nucleopolyhedrovirus (ChinNPV) and its contribution
to the variability of the virus under laboratory conditions. A mixture of natural isolates (ChinNPVMex1)
contained two genetic variants that dominated over other variants in individual larvae that
consumed high (ChinNPV-K) and low (ChinNPV-E) concentrations of inoculum. Studies on the
ChinNPV-K variant indicated that it was capable of generating novel variation in a concentrationdependent
manner. In cell culture, cells inoculated with high concentrations of ChinNPV-K produced
OBs with the ChinNPV-K REN profile, whereas a high diversity of ChinNPV variants was recovered
following plaque purification of low concentrations of ChinNPV-K virion inoculum. Interestingly,
the ChinNPV-K variant could not be recovered from plaques derived from low concentration inocula
originating from budded virions or occlusion-derived virions of ChinNPV-K. Genome sequencing
revealed marked differences between ChinNPV-K and ChinNPV-E, with high variation in the
ChinNPV-K genome, mostly due to single nucleotide polymorphisms. We conclude that ChinNPV-K
is an unstable genetic variant that is responsible for generating much of the detected variability in
the natural ChinNPV isolates used in this study.
