Changes in the Nuclei of Infected Cells at Early Stages of Infection with EMCV

Zaven A. Karalyan, Hranush R. Avagyan, Hovakim S. Zakaryan, Liana O. Abroyan, Lina H. Hakobyan, Aida S. Avetisyan, Elena M. Karalova

Institute of Molecular Biology of the National Academy of Sciences of the Republic of Armenia, Laboratory of Cell Biology, Yerevan, Armenia.

DOI: 10.4236/cellbio.2013.23014                

Abstract

By the methods of quantitative cytophotometry, we have identified the changes in the nucleus and of some intranuclear compartments in the early stages of infection with encephalomyocarditis virus (EMCV). They can be characterized as early 1 - 2 hours post infection (hpi) and temporary increase (duration about 1 hour) in the content of the acidic proteins of the nucleolus, changing their decline to the control values. Then (after 1 - 2 hours) follows an increase in RNA content of nucleoli to 4 hours post infection (the process takes about 2 hours). The increase in RNA content in nucleoli is in approximately the same time (slightly behind) with the activation of PML bodies (2 - 4 hpi). Then, the RNA content in nucleoli decreased to the control values, while simultaneously decreasing activity of PML bodies (ranging from 5 - 6 hpi). The early stages of infection EMCV are also characterized by the tendency to increase in the size of the nuclei of infected cells, and preserve at a later time. Then there is an increase in RNA content in the nucleus, roughly coinciding with the increased content of RNA in the nucleoli.

Keywords

EMCV; Acidic Proteins; RNA; Nucleolus; Nucleus

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	R. Groppo, B. A. Brown and A. C. Palmenberg, “Mutational Analysis of the EMCV 2A Protein Identifies a Nuclear Localization Signal and an eIF4E Binding Site,” Virology, Vol. 410, No. 1, 2011, pp. 257-267. doi:10.1016/j.virol.2010.11.002
[2]	A. G. Aminev, S. P. Amineva and A. C. Palmenberg, “Encephalomyocarditis Viral Protein 2A Localizes to Nucleoli and Inhibits Cap-Dependent mRNA Transla- tion,” Virus Research, Vol. 95, No. 1-2, 2003, pp. 45-57. doi:10.1016/S0168-1702(03)00162-X
[3]	A. G. Aminev, S. P. Amineva and A. C. Palmenberg, “Encephalomyocarditis Virus (EMCV) Proteins 2A and 3BCD Localize to Nuclei and Inhibit Cellular mRNA Transcription but Not rRNA Transcription,” Virus Research, Vol. 95, No. 1-2, 2003, pp. 59-73. doi:10.1016/S0168-1702(03)00163-1
[4]	A. D. Deich, “Introduction to Quantitative Cytochemistry,” Academic Press New York/London, 1966, pp. 65-67.
[5]	W. Sandritter, G. Kifer and W. Rik, “Gallocyaninchromalum Stain,” In: G. L. Wied, Ed., Introduction to Quantitative Cytochemistry, Academic Press, New York and London, 1966, pp. 153-170.
[6]	A. C. Dhar and C. K. Shah, “Cytochemical Method to Localize Acidic Nuclear Proteins,” Stain Technology, Vol. 57, No. 3, 1982, pp. 151-155.
[7]	B. R. Zirkin, “A cytochemical Study of the Nonhistone Protein Content of Condensed and Extended Chromatin,” Experimental Cell Research, Vol. 78, No. 2, 1973, pp. 394-398. doi:10.1016/0014-4827(73)90084-0
[8]	C. C. Yin, A. B. Glassman, P. Lin, J. R. Valbuena, D. Jones, R. Luthra and L. J. Medeiros, “Morphologic, Cytogenetic, and Molecular Abnormalities in Therapy-Related Acute Promyelocytic Leukemia,” American Journal of Clinical Pathology, Vol. 123, No. 6, 2005, pp. 840-848. doi:10.1309/TJFFK819RPCLFKJ0
[9]	C. C. Morton, J. A. Brown, W. M. Holmes, W. E. Nance and B. Wolf, “Stain Intensity of Human Nucleolus Organizer Region Reflects Incorporation of Uridine in to Mature Ribosomal RNA,” Experimental Cell Research, Vol. 145, No. 2, 1983, pp. 405-413. doi:10.1016/0014-4827(83)90019-8
[10]	H. Zakaryan and T. Stamminger, “Nuclear Remodelling during Viral Infections,” Cellular Microbiology, Vol. 13, No. 6, 2011, pp. 806-813. doi:10.1111/j.1462-5822.2011.01596.x
[11]	B. El McHichi, T. Regad, M. A. Maroui, M. S. Rodriguez, A. Aminev, S. Gerbaud, N. Escriou, L. Dianoux and M. K. Chelbi-Alix, “SUMOylation Promotes PML Degradation during Encephalomyocarditis Virus Infection,” Journal of Virology, Vol. 84, No. 22, 2010, pp. 11634-11645. doi:10.1128/JVI.01321-10
[12]	R. Baserga and G. Stein, “Nuclear Acidic Proteins and Cell Proliferation,” Federation Proceedings, Vol. 30, No. 6, 1971, pp. 1752-1759.
[13]	G. Stein and R. Baserga, “Cytoplasmic Synthesis of Acidic Chromosomal Proteins,” Biochemical and Biophysical Research Communications, Vol. 44, No. 1, 1971, pp. 218-223.
[14]	F. Thiebaut, J. P. Rigaut and A. Reith, “Improvement in the Specificity of the Silver Staining Technique for AgNOR-Associated Acidic Proteins in Paraffin Sections,” Stain Technology, Vol. 59, No. 3, 1984, pp. 181-188.
[15]	M. Okuwaki, “The Structure and Functions of NPM1/ Nucleophsmin/B23, a Multifunctional Nucleolar Acidic Protein,” The Journal of Biochemistry, Vol. 143, No. 4, 2008, pp. 441-448. doi:10.1093/jb/mvm222
[16]	E. A. Sorokina, J. A. Wesson and J. G. Kleinman, “An Acidic Peptide Sequence of Nucleolin-Related Protein Can Mediate the Attachment of Calcium Oxalate to Renal Tubule Cells,” Journal of the American Society of Nephrology, Vol. 15, No. 8, 2004, pp. 2057-2065. doi:10.1097/01.ASN.0000133024.83256.C8
[17]	R. Voit, A. Kuhn, E. E. Sander and I. Grummt, “Activation of Mammalian Ribosomal Gene Transcription Requires Phosphorylation of the Nucleolar Trans- cription Factor UBF,” Nucleic Acids Research, Vol. 23, No. 14, 1995, pp. 2593-2599. doi:10.1093/nar/23.14.2593
[18]	Y. V. Svitkin and N. Sonenberg, “Cell-Free Synthesis of Encephalomyocarditis Virus,” Journal of Virology, Vol. 77, No. 11, 2003, pp. 6551-6555. doi:10.1128/JVI.77.11.6551-6555.2003
[19]	A. S. Stoykova, M. D. Dabeva, R. N. Dimova and A. A. Hadjiolov, “Ribosome Biogenesis and Nucleolar Ultrastructure in Neuronal and Oligodendroglial Rat Brain Cells,” Journal of Neurochemistry, Vol. 45, No. 6, 1985, pp. 1667-1676. doi:10.1111/j.1471-4159.1985.tb10521.x