دورية أكاديمية

Identification and Functional Characterization of Phosphorylation Sites of the Human Papillomavirus 31 E8^E2 Protein.

التفاصيل البيبلوغرافية
العنوان: Identification and Functional Characterization of Phosphorylation Sites of the Human Papillomavirus 31 E8^E2 Protein.
المؤلفون: van de Poel, Saskia1, Dreer, Marcel1, Velic, Ana2, Macek, Boris2, Baskaran, Praveen3, Iftner, Thomas1, Stubenrauch, Frank1 frank.stubenrauch@med.uni-tuebingen.de
المصدر: Journal of Virology. Feb2018, Vol. 92 Issue 4, p1-17. 17p.
مصطلحات موضوعية: *PHOSPHORYLATION, *PAPILLOMAVIRUSES, *MASS spectrometry, *PROTEIN stability, *VIRAL replication
مستخلص: The papillomavirus E2 protein regulates transcription, replication, and nuclear retention of viral genomes. Phosphorylation of E2 in the hinge region has been suggested to modulate protein stability, DNA-binding activity, and chromosomal attachment. The papillomavirus E8^E2 protein shares the hinge domain with E2 and acts as a repressor of viral replication. Mass spectrometry analyses of human papillomavirus 31 (HPV31) E8^E2 and E2 proteins identify phosphorylated S78, S81, and S100 in E8^E2 and S266 and S269 in E2 in their hinge regions. Phos-tag analyses of wild-type and mutant proteins indicate that S78 is a major phosphorylation site in E8^E2, but the corresponding S266 in E2 is not. Phosphorylation at S78 regulates E8^E2's repression activity of reporter constructs, whereas the corresponding E2 mutants do not display a phenotype. Phosphorylation at S78 does not alter E8^E2's protein stability, nuclear localization, or binding to DNA or to cellular NCoR/SMRT complexes. Surprisingly, in the context of HPV31 genomes, mutation of E8^E2 S78 does not modulate viral replication or transcription in undifferentiated or differentiated cells. However, comparative transcriptome analyses of differentiated HPV31 E8^E2 S78A and S78E cell lines reveal that the expression of a small number of cellular genes is changed. Validation experiments suggest that the transcription of the cellular LYPD2 gene is altered in a phospho-S78 E8^E2-dependent manner. In summary, our data suggest that phosphorylation of S78 in E8^E2 regulates its repression activity by a novel mechanism, and this seems to be important for the modulation of host cell gene expression but not viral replication. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:0022538X
DOI:10.1128/JVI.01743-17