The Protamine-like DNA-binding Protein P6.9 Epigenetically Up-regulates Autographa californica Multiple Nucleopolyhedrovirus Gene Transcription in the Late Infection Phase
10.1007/s12250-012-3229-x
- Author:
Ying PENG
;
Kun LI
;
Rongjuan PEI
;
Chunchen WU
;
Changyong LIANG
;
Yun WANG
;
Xinwen CHEN
- Publication Type:Journal Article
- Keywords:
Epigenetics;
AcMNPV;
P6.9;
Protamine;
Subnucleosome
- From:
Virologica Sinica
2012;27(1):57-68
- CountryChina
- Language:Chinese
-
Abstract:
Protamines are a group of highly basic proteins first discovered in spermatozoon that allow for denser packaging of DNA than histones and will result in down-regulation of gene transcription[1].It is well recognized that the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) encodes P6.9,a protamine-like protein that forms the viral subnucleosome through binding to the viral genome[29].Previous research demonstrates that P6.9 is essential for viral nucleocapsid assembly,while it has no influence on viral genome replication[31].In the present study,the role of P6.9 in viral gene transcription regulation is characterized.In contrast to protamines or other protamine-like proteins that usually down-regulate gene transcription,P6.9 appears to up-regulate viral gene transcription at 12-24 hours post infection (hpi),whereas it is non-essential for the basal level of viral gene transcription.Fluorescence microscopy reveals the P6.9's co-localization with DNA is temporally and spatially synchronized with P6.9's impact on viral gene transcription,indicating the P6.9-DNA association contributes to transcription regulation.Chromatin fractionation assay further reveals an unexpected co-existence of P6.9 and host RNA polymerase Ⅱ in the same transcriptionally active chromatin fraction at 24 hpi,which may probably contribute to viral gene transcription up-regulation in the late infection phase.
