The Cyclin-Dependent Kinase Ortholog pUL97 of Human Cytomegalovirus Interacts with Cyclins
by
Laura Graf 1, Rike Webel 1, Sabrina Wagner 1, Stuart T. Hamilton 2, William D. Rawlinson 2, Heinrich Sticht 3 and Manfred Marschall 1,*
Laura Graf 1, Rike Webel 1, Sabrina Wagner 1, Stuart T. Hamilton 2, William D. Rawlinson 2, Heinrich Sticht 3 and Manfred Marschall 1,*
1
Institute for Clinical and Molecular Virology, University of Erlangen-Nuremberg, 91054 Erlangen, Germany
2
Virology Division, SEALS, Department of Microbiology, Prince of Wales Hospital, Randwick, NSW 2031, Sydney, Australia
3
Division of Bioinformatics, Institute of Biochemistry, University of Erlangen-Nuremberg, 91054 Erlangen, Germany
*
Author to whom correspondence should be addressed.
Viruses 2013, 5(12), 3213-3230; https://doi.org/10.3390/v5123213
Received: 14 November 2013 / Revised: 8 December 2013 / Accepted: 9 December 2013 / Published: 18 December 2013
(This article belongs to the Special Issue Recent CMV Research)
The human cytomegalovirus (HCMV)-encoded protein kinase, pUL97, is considered a cyclin-dependent kinase (CDK) ortholog, due to shared structural and functional characteristics. The primary mechanism of CDK activation is binding to corresponding cyclins, including cyclin T1, which is the usual regulatory cofactor of CDK9. This study provides evidence of direct interaction between pUL97 and cyclin T1 using yeast two-hybrid and co-immunoprecipitation analyses. Confocal immunofluorescence revealed partial colocalization of pUL97 with cyclin T1 in subnuclear compartments, most pronounced in viral replication centres. The distribution patterns of pUL97 and cyclin T1 were independent of HCMV strain and host cell type. The sequence domain of pUL97 responsible for the interaction with cyclin T1 was between amino acids 231–280. Additional co-immunoprecipitation analyses showed cyclin B1 and cyclin A as further pUL97 interaction partners. Investigation of the pUL97-cyclin T1 interaction in an ATP consumption assay strongly suggested phosphorylation of pUL97 by the CDK9/cyclin T1 complex in a substrate concentration-dependent manner. This is the first demonstration of interaction between a herpesviral CDK ortholog and cellular cyclins.
View Full-Text
Keywords:
human cytomegalovirus; protein kinase pUL97; cyclins T1, B1 and A; protein-protein interaction; substrate phosphorylation; interaction-mediated regulation
▼
Show Figures
Figure 1
This is an open access article distributed under the Creative Commons Attribution License
MDPI and ACS Style
Graf, L.; Webel, R.; Wagner, S.; Hamilton, S.T.; Rawlinson, W.D.; Sticht, H.; Marschall, M. The Cyclin-Dependent Kinase Ortholog pUL97 of Human Cytomegalovirus Interacts with Cyclins. Viruses 2013, 5, 3213-3230.
Show more citation formats
