biostudies-literatureUnknown8(7)Li BHistone H3-lysine(9) (H3K9) trimethyltransferase gene Su(var) 3-9 was cloned and identified in three Spodoptera insects, Spodopterafrugiperda (S. frugiperda), S. exigua and S. litura. Sequence analysis showed that Spodoptera Su(var) 3-9 is highly conserved evolutionarily. Su(var) 3-9 protein was found to be localized in the nucleus in Sf9 cells, and interact with histone H3, and the heterochromatin protein 1a (HP1a) and HP1b. A dose-dependent enzymatic activity was found at both 27 °C and 37 °C in vitro, with higher activity at 27 °C. Addition of specific inhibitor chaetocin resulted in decreased histone methylation level and host chromatin relaxation. In contrast, overexpression of Su(var) 3-9 caused increased histone methylation level and cellular genome compaction. In AcMNV-infected Sf9PloS onee69442https://www.ebi.ac.uk/biostudies/studies/S-EPMC3722159biostudies-literatureIdentification and characterization of the Spodoptera Su(var) 3-9 histone H3K9 trimethyltransferase and its effect in AcMNPV infection.PMC3722159Li SLi BZhong JYin JfalseIdentification and characterization of the Spodoptera Su(var) 3-9 histone H3K9 trimethyltransferase and its effect in AcMNPV infection.Histone H3-lysine(9) (H3K9) trimethyltransferase gene Su(var) 3-9 was cloned and identified in three Spodoptera insects, Spodopterafrugiperda (S. frugiperda), S. exigua and S. litura. Sequence analysis showed that Spodoptera Su(var) 3-9 is highly conserved evolutionarily. Su(var) 3-9 protein was found to be localized in the nucleus in Sf9 cells, and interact with histone H3, and the heterochromatin protein 1a (HP1a) and HP1b. A dose-dependent enzymatic activity was found at both 27 °C and 37 °C in vitro, with higher activity at 27 °C. Addition of specific inhibitor chaetocin resulted in decreased histone methylation level and host chromatin relaxation. In contrast, overexpression of Su(var) 3-9 caused increased histone methylation level and cellular genome compaction. In AcMNV-infected Sf92013-01-01T00:00:00Z20132025-04-04T08:00:50.804Z2019-03-26T23:15:12ZS-EPMC37221592389448010.1371/journal.pone.0069442