Journal of General Virology, Vol 80, 1293-1303, Copyright © 1999 by Society for General Microbiology

ARTICLES

Domain mapping of the human cytomegalovirus IE1-72 and cellular p107 protein--protein interaction and the possible functional consequences

RA Johnson, AD Yurochko, EE Poma, L Zhu and ES Huang
Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7295, USA

Our previous work demonstrated that following human cytomegalovirus (HCMV) infection of fibroblasts, there was a protein--protein interaction between the HCMV IE1-72 immediate-early (IE) protein and the cellular p107 protein which resulted in the alleviation of p107-mediated transcriptional repression of E2F-responsive promoters. In a further characterization of this interaction, we now show that IE1-72 binds to the N-terminal portion of p107, not the C-terminal 'pocket' region that binds E2F-4, and where a number of other viral gene products bind. Additionally, we show that exons 2 and 3 of IE1-72 are required for binding to p107. After mapping the binding domains, we next wanted to address the additional functional consequences of this interaction. It is well known that p107 can negatively regulate cell growth. To examine whether IE1-72 can also overcome this growth suppression, we transfected and infected or cotransfected various constructs into SAOS-2 cells. We showed that infection of SAOS-2 cells was capable of alleviating p107-mediated growth suppression. Additionally, we showed that IE1-72 alone is capable of overcoming p107-mediated growth arrest. Alleviation of this repression by IE1-72 is dependent on the protein--protein interaction between p107 and IE1-72 as deletion mutants of either protein which lack the identified binding domains fail to achieve this effect. These data indicate that the IE1-72 protein is capable of overcoming p107-mediated blocks in cellular proliferation, events that occur in both productive and non-productive HCMV infections.

This article has been cited by other articles:

				K. Koh, K. Lee, J.-H. Ahn, and S. Kim Human cytomegalovirus infection downregulates the expression of glial fibrillary acidic protein in human glioblastoma U373MG cells: identification of viral genes and protein domains involved J. Gen. Virol., April 1, 2009; 90(4): 954 - 962. [Abstract] [Full Text] [PDF]

				M. N. Prichard, E. Sztul, S. L. Daily, A. L. Perry, S. L. Frederick, R. B. Gill, C. B. Hartline, D. N. Streblow, S. M. Varnum, R. D. Smith, et al. Human Cytomegalovirus UL97 Kinase Activity Is Required for the Hyperphosphorylation of Retinoblastoma Protein and Inhibits the Formation of Nuclear Aggresomes J. Virol., May 15, 2008; 82(10): 5054 - 5067. [Abstract] [Full Text] [PDF]

				E. A. White and D. H. Spector Exon 3 of the Human Cytomegalovirus Major Immediate-Early Region Is Required for Efficient Viral Gene Expression and for Cellular Cyclin Modulation J. Virol., June 15, 2005; 79(12): 7438 - 7452. [Abstract] [Full Text] [PDF]

				J. Reinhardt, G. B. Smith, C. T. Himmelheber, J. Azizkhan-Clifford, and E. S. Mocarski The Carboxyl-Terminal Region of Human Cytomegalovirus IE1491aa Contains an Acidic Domain That Plays a Regulatory Role and a Chromatin-Tethering Domain That Is Dispensable during Viral Replication J. Virol., January 1, 2005; 79(1): 225 - 233. [Abstract] [Full Text] [PDF]

				Z. Wang, C. La Rosa, S. Mekhoubad, S. F. Lacey, M. C. Villacres, S. Markel, J. Longmate, J. D. I. Ellenhorn, R. F. Siliciano, C. Buck, et al. Attenuated poxviruses generate clinically relevant frequencies of CMV-specific T cells Blood, August 1, 2004; 104(3): 847 - 856. [Abstract] [Full Text] [PDF]

				M. S. Smith, G. L. Bentz, J. S. Alexander, and A. D. Yurochko Human Cytomegalovirus Induces Monocyte Differentiation and Migration as a Strategy for Dissemination and Persistence J. Virol., May 1, 2004; 78(9): 4444 - 4453. [Abstract] [Full Text] [PDF]

				Z. Zhang, S.-M. Huong, X. Wang, D. Y. Huang, and E.-S. Huang Interactions between Human Cytomegalovirus IE1-72 and Cellular p107: Functional Domains and Mechanisms of Up-Regulation of Cyclin E/cdk2 Kinase Activity J. Virol., December 1, 2003; 77(23): 12660 - 12670. [Abstract] [Full Text] [PDF]

				G. Chan, D. G. Hemmings, A. D. Yurochko, and L. J. Guilbert Human Cytomegalovirus-Caused Damage to Placental Trophoblasts Mediated by Immediate-Early Gene-Induced Tumor Necrosis Factor-{alpha} Am. J. Pathol., October 1, 2002; 161(4): 1371 - 1381. [Abstract] [Full Text] [PDF]

				Z. Chen, E. Knutson, A. Kurosky, and T. Albrecht Degradation of p21cip1 in Cells Productively Infected with Human Cytomegalovirus J. Virol., April 15, 2001; 75(8): 3613 - 3625. [Abstract] [Full Text]

				J. P. Castillo, A. D. Yurochko, and T. F. Kowalik Role of Human Cytomegalovirus Immediate-Early Proteins in Cell Growth Control J. Virol., September 1, 2000; 74(17): 8028 - 8037. [Abstract] [Full Text]