Skip to main content

Quantitative Electron Microscopy to Study HCMV Morphogenesis

  • Protocol
  • First Online:
Human Cytomegaloviruses

Part of the book series: Methods in Molecular Biology ((MIMB,volume 2244))

Abstract

The generation and release of mature virions from human cytomegalovirus (HCMV) infected cells is a multistep process, involving a profound reorganization of cellular structures and various stages of virus particle morphogenesis in different cellular compartments. Although the general steps of HCMV morphogenesis are known, it has become clear that the detailed molecular mechanisms are complex and dependent on various viral factors and cellular pathways. The lack of a full understanding of HCMV virion morphogenesis emphasizes the need of imaging techniques to visualize the different stages of virion assembly, such as electron microscopy. Here, we describe various electron microscopy techniques and the methodology of high-pressure freezing and freeze substitution for sample preparation to visualize HCMV morphogenesis. These methods are used in our laboratory in combination with a thorough quantification to characterize phenotypic alterations and to identify the function of viral and cellular proteins for the various morphogenesis stages.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Protocol
USD 49.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 139.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 179.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 249.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Similar content being viewed by others

References

  1. Mocarski E, Shenk T, Pass R (2006) Cytomegaloviruses. In: Knipe DM, Howley PM, Griffin DE et al (eds) Fields virology, 5th edn. Lippincott Williams & Wilkins, Philadelphia, PA, pp 2701–2771

    Google Scholar 

  2. Varnum SM, Streblow DN, Monroe ME et al (2004) Identification of proteins in human cytomegalovirus (HCMV) particles: the HCMV proteome. J Virol 78:10960–10966. https://doi.org/10.1128/JVI.78.20.10960-10966.2004

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Mettenleiter TC (2004) Budding events in herpesvirus morphogenesis. Virus Res 106:167–180. https://doi.org/10.1016/j.virusres.2004.08.013

    Article  CAS  PubMed  Google Scholar 

  4. Mettenleiter TC (2002) Herpesvirus assembly and egress. J Virol 76:1537–1547. https://doi.org/10.1128/JVI.76.4.1537-1547.2002

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Severi B, Landini MP, Govoni E (1988) Human cytomegalovirus morphogenesis: an ultrastructural study of the late cytoplasmic phases. Arch Virol 98:51–64. https://doi.org/10.1007/bf01321005

    Article  CAS  PubMed  Google Scholar 

  6. Schauflinger M, Villinger C, Mertens T et al (2013) Analysis of human cytomegalovirus secondary envelopment by advanced electron microscopy: HCMV morphogenesis. Cell Microbiol 15:305–314. https://doi.org/10.1111/cmi.12077

    Article  CAS  PubMed  Google Scholar 

  7. Seo J-Y, Britt WJ (2007) Cytoplasmic envelopment of human cytomegalovirus requires the postlocalization function of tegument protein pp28 within the assembly compartment. J Virol 81:6536–6547. https://doi.org/10.1128/JVI.02852-06

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Gibson W, Bogner E (2013) Morphogenesis of the cytomegalovirus Virion and subviral particles. In: Reddehase MJ (ed) Cytomegaloviruses: from molecular pathogenesis to intervention, 2nd edn. Caister Academic Press, Norfolk, pp 230–246

    Google Scholar 

  9. Walther P, Wang L, Ließem S, Frascaroli G (2010) Viral infection of cells in culture: approaches for electron microscopy. In: Müller-Reichert T (ed) Methods in cell biology. Academic, Cambridge, MA, pp 603–618. https://doi.org/10.1016/S0091-679X(10)96025-1

    Chapter  Google Scholar 

  10. Gibson W (1996) Structure and assembly of the virion. Intervirology 39:389–400. https://doi.org/10.1159/000150509

    Article  CAS  PubMed  Google Scholar 

  11. Yu X, Trang P, Shah S et al (2005) Dissecting human cytomegalovirus gene function and capsid maturation by ribozyme targeting and electron cryomicroscopy. Proc Natl Acad Sci U S A 102:7103–7108. https://doi.org/10.1073/pnas.0408826102

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Cardone G, Heymann JB, Cheng N et al (2012) Procapsid assembly, maturation, nuclear exit: dynamic steps in the production of infectious Herpesvirions. Adv Exp Med Biol 726:423–439. https://doi.org/10.1007/978-1-4614-0980-9_19

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Tandon R, Mocarski ES, Conway JF (2015) The A, B, Cs of herpesvirus capsids. Viruses 7:899–914. https://doi.org/10.3390/v7030899

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Mettenleiter TC, Müller F, Granzow H, Klupp BG (2013) The way out: what we know and do not know about herpesvirus nuclear egress. Cell Microbiol 15:170–178. https://doi.org/10.1111/cmi.12044

    Article  CAS  PubMed  Google Scholar 

  15. Milbradt J, Auerochs S, Sticht H, Marschall M (2009) Cytomegaloviral proteins that associate with the nuclear lamina: components of a postulated nuclear egress complex. J Gen Virol 90:579–590. https://doi.org/10.1099/vir.0.005231-0

    Article  CAS  PubMed  Google Scholar 

  16. Muranyi W, Haas J, Wagner M et al (2002) Cytomegalovirus recruitment of cellular kinases to dissolve the nuclear lamina. Science 297:854–857. https://doi.org/10.1126/science.1071506

    Article  CAS  PubMed  Google Scholar 

  17. Sharma M, Kamil JP, Coughlin M et al (2014) Human cytomegalovirus UL50 and UL53 recruit viral protein kinase UL97, not protein kinase C, for disruption of nuclear lamina and nuclear egress in infected cells. J Virol 88:249–262. https://doi.org/10.1128/JVI.02358-13

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Buser C, Walther P, Mertens T, Michel D (2007) Cytomegalovirus primary envelopment occurs at large Infoldings of the inner nuclear membrane. J Virol 81:3042–3048. https://doi.org/10.1128/JVI.01564-06

    Article  CAS  PubMed  Google Scholar 

  19. Villinger C, Neusser G, Kranz C et al (2015) 3D analysis of HCMV induced-nuclear membrane structures by FIB/SEM tomography: insight into an unprecedented membrane morphology. Viruses 7:5686–5704. https://doi.org/10.3390/v7112900

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Bigalke JM, Heuser T, Nicastro D, Heldwein EE (2014) Membrane deformation and scission by the HSV-1 nuclear egress complex. Nat Commun 5:4131. https://doi.org/10.1038/ncomms5131

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Bigalke JM, Heldwein EE (2015) Structural basis of membrane budding by the nuclear egress complex of herpesviruses. EMBO J 34(23):2921–2936. https://doi.org/10.15252/embj.201592359

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Bigalke JM, Heldwein EE (2015) The great (nuclear) escape: new insights into the role of the nuclear egress complex of herpesviruses. J Virol 89:9150–9153. https://doi.org/10.1128/JVI.02530-14

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Hagen C, Dent KC, Zeev-Ben-Mordehai T et al (2015) Structural basis of vesicle formation at the inner nuclear membrane. Cell 163:1692–1701. https://doi.org/10.1016/j.cell.2015.11.029

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Klupp BG, Granzow H, Fuchs W et al (2007) Vesicle formation from the nuclear membrane is induced by coexpression of two conserved herpesvirus proteins. Proc Natl Acad Sci U S A 104:7241–7246. https://doi.org/10.1073/pnas.0701757104

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Lorenz M, Vollmer B, Unsay JD et al (2015) A single herpesvirus protein can mediate vesicle formation in the nuclear envelope. J Biol Chem 290:6962–6974. https://doi.org/10.1074/jbc.M114.627521

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Sanchez V, Greis KD, Sztul E, Britt WJ (2000) Accumulation of virion tegument and envelope proteins in a stable cytoplasmic compartment during human cytomegalovirus replication: characterization of a potential site of virus assembly. J Virol 74:975–986. https://doi.org/10.1128/JVI.74.2.975-986.2000

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Sanchez V, Sztul E, Britt WJ (2000) Human cytomegalovirus pp28 (UL99) localizes to a cytoplasmic compartment which overlaps the endoplasmic reticulum-golgi-intermediate compartment. J Virol 74:3842–3851. https://doi.org/10.1128/jvi.74.8.3842-3851.2000

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Homman-Loudiyi M, Hultenby K, Britt W, Soderberg-Naucler C (2003) Envelopment of human cytomegalovirus occurs by budding into Golgi-derived vacuole compartments positive for gB, Rab 3, trans-Golgi network 46, and mannosidase II. J Virol 77:3191–3203. https://doi.org/10.1128/JVI.77.5.3191-3203.2003

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Das S, Vasanji A, Pellett PE (2007) Three-dimensional structure of the human cytomegalovirus cytoplasmic virion assembly complex includes a reoriented secretory apparatus. J Virol 81:11861–11869. https://doi.org/10.1128/JVI.01077-07

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Das S, Pellett PE (2011) Spatial relationships between markers for secretory and endosomal machinery in human cytomegalovirus-infected cells versus those in uninfected cells. J Virol 85:5864–5879. https://doi.org/10.1128/JVI.00155-11

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Alwine JC (2012) The human cytomegalovirus assembly compartment: a masterpiece of viral manipulation of cellular processes that facilitates assembly and egress. PLoS Pathog 8:e1002878. https://doi.org/10.1371/journal.ppat.1002878

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Ogawa-Goto K, Tanaka K, Gibson W et al (2003) Microtubule network facilitates nuclear targeting of human cytomegalovirus capsid. J Virol 77:8541–8547. https://doi.org/10.1128/JVI.77.15.8541-8547.2003

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Yu X, Shah S, Lee M et al (2011) Biochemical and structural characterization of the capsid-bound tegument proteins of human cytomegalovirus. J Struct Biol 174:451–460. https://doi.org/10.1016/j.jsb.2011.03.006

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Guo H, Shen S, Wang L, Deng H (2010) Role of tegument proteins in herpesvirus assembly and egress. Protein Cell 1:987–998. https://doi.org/10.1007/s13238-010-0120-0

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Smith RM, Kosuri S, Kerry JA (2014) Role of human cytomegalovirus tegument proteins in virion assembly. Viruses 6:582–605. https://doi.org/10.3390/v6020582

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  36. Read C, Schauflinger M, Nikolaenko D et al (2019) Regulation of human cytomegalovirus secondary envelopment by a C-terminal tetra-lysine motif in pUL71. J Virol 93:e02244-18. https://doi.org/10.1128/JVI.02244-18

    Article  PubMed  PubMed Central  Google Scholar 

  37. Chevillotte M, Landwehr S, Linta L et al (2008) Major tegument protein pp65 of human cytomegalovirus is required for the incorporation of pUL69 and pUL97 into the virus particle and for viral growth in macrophages. J Virol 83:2480–2490. https://doi.org/10.1128/JVI.01818-08

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Meissner CS, Suffner S, Schauflinger M et al (2011) A leucine zipper motif of a tegument protein triggers final envelopment of human cytomegalovirus. J Virol 86:3370–3382. https://doi.org/10.1128/JVI.06556-11

    Article  CAS  PubMed  Google Scholar 

  39. Schauflinger M, Fischer D, Schreiber A et al (2011) The tegument protein UL71 of human cytomegalovirus is involved in late envelopment and affects multivesicular bodies. J Virol 85:3821–3832. https://doi.org/10.1128/JVI.01540-10

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Ahlqvist J, Mocarski E (2011) Cytomegalovirus UL103 controls virion and dense body egress. J Virol 85:5125–5135. https://doi.org/10.1128/JVI.01682-10

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Phillips SL, Bresnahan WA (2012) The human cytomegalovirus (HCMV) tegument protein UL94 is essential for secondary envelopment of HCMV virions. J Virol 86:2523–2532. https://doi.org/10.1128/JVI.06548-11

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Kim Y-E, Oh SE, Kwon KM et al (2016) Involvement of the N-terminal DUB domain of human cytomegalovirus UL48 tegument protein in auto-ubiquitination, virion stability, virus entry. J Virol 90(6):3229–3242. https://doi.org/10.1128/JVI.02766-15

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Brock I, Kruger M, Mertens T, von Einem J (2013) Nuclear targeting of human cytomegalovirus large tegument protein pUL48 is essential for viral growth. J Virol 87:6005–6019. https://doi.org/10.1128/JVI.03558-12

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Moor H (1987) Theory and practice of high pressure freezing. In: Steinbrecht RA, Zierold K (eds) Cryotechniques in biological electron microscopy. Springer, Berlin, pp 175–191. https://doi.org/10.1007/978-3-642-72815-0_8

    Chapter  Google Scholar 

  45. Walther P, Ziegler A (2002) Freeze substitution of high-pressure frozen samples: the visibility of biological membranes is improved when the substitution medium contains water. J Microsc 208:3–10. https://doi.org/10.1046/j.1365-2818.2002.01064.x

    Article  CAS  PubMed  Google Scholar 

  46. Buser C, Walther P (2008) Freeze-substitution: the addition of water to polar solvents enhances the retention of structure and acts at temperatures around −60°C. J Microsc 230:268–277. https://doi.org/10.1111/j.1365-2818.2008.01984.x

    Article  CAS  PubMed  Google Scholar 

  47. Szczesny PJ, Walther P, Müller M (1996) Light damage in rod outer segments: the effects of fixation on ultrastructural alterations. Curr Eye Res 15:807–814. https://doi.org/10.3109/02713689609017621

    Article  CAS  PubMed  Google Scholar 

  48. Schauflinger M, Villinger C, Walther P (2013) Three-dimensional visualization of virus-infected cells by serial sectioning: an electron microscopic study using resin embedded cells. In: Bailer S, Lieber D (eds) Virus-host interactions. Methods in molecular biology (methods and protocols). Humana Press, Totowa, NJ, pp 227–237. https://doi.org/10.1007/978-1-62703-601-6_16

    Chapter  Google Scholar 

  49. Villinger C, Schauflinger M, Gregorius H et al (2013) Three-dimensional imaging of adherent cells using FIB/SEM and STEM. In: Kuo J (ed) Methods in molecular biology (methods and protocols). Humana Press, Totowa, NJ, pp 617–638. https://doi.org/10.1007/978-1-62703-776-1_27

    Chapter  Google Scholar 

  50. Shaga-Devan K, Walther P, von Einem J et al (2019) Detection of herpesvirus capsids in transmission electron microscopy images using transfer learning. Histochem Cell Biol 151:101–114. https://doi.org/10.1007/s00418-018-1759-5

    Article  CAS  Google Scholar 

  51. Romero-Brey I, Bartenschlager R (2015) Viral infection at high magnification: 3D electron microscopy methods to analyze the architecture of infected cells. Viruses 7:6316–6345. https://doi.org/10.3390/v7122940

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Risco C, de Castro IF, Sanz-Sánchez L et al (2014) Three-dimensional imaging of viral infections. Annu Rev Virol 1:453–473. https://doi.org/10.1146/annurev-virology-031413-085351

    Article  CAS  PubMed  Google Scholar 

  53. McDonald KL, Webb RI (2011) Freeze substitution in 3 hours or less. J Microsc 243:227–233. https://doi.org/10.1111/j.1365-2818.2011.03526.x

    Article  CAS  PubMed  Google Scholar 

  54. Abdellatif MEA, Sinzger C, Walther P (2018) Investigating HCMV entry into host cells by STEM tomography. J Struct Biol 204:406–419. https://doi.org/10.1016/j.jsb.2018.10.007

    Article  PubMed  Google Scholar 

  55. Aoyama K, Takagi T, Hirase A, Miyazawa A (2008) STEM tomography for thick biological specimens. Ultramicroscopy 109:70–80. https://doi.org/10.1016/j.ultramic.2008.08.005

    Article  CAS  PubMed  Google Scholar 

  56. Höhn K, Sailer M, Wang L et al (2011) Preparation of cryofixed cells for improved 3D ultrastructure with scanning transmission electron tomography. Histochem Cell Biol 135:1–9. https://doi.org/10.1007/s00418-010-0765-z

    Article  CAS  PubMed  Google Scholar 

  57. Walther P, Bauer A, Wenske N et al (2018) STEM tomography of high-pressure frozen and freeze-substituted cells: a comparison of image stacks obtained at 200 kV or 300 kV. Histochem Cell Biol 150:545–556. https://doi.org/10.1007/s00418-018-1727-0

    Article  CAS  PubMed  Google Scholar 

  58. Yakushevska AE, Lebbink MN, Geerts WJC et al (2007) STEM tomography in cell biology. J Struct Biol 159:381–391. https://doi.org/10.1016/j.jsb.2007.04.006

    Article  CAS  PubMed  Google Scholar 

  59. Villinger C, Gregorius H, Kranz C et al (2012) FIB/SEM tomography with TEM-like resolution for 3D imaging of high-pressure frozen cells. Histochem Cell Biol 138:549–556. https://doi.org/10.1007/s00418-012-1020-6

    Article  CAS  PubMed  Google Scholar 

  60. Kizilyaprak C, Daraspe J, Humbel B m. (2014) Focused ion beam scanning electron microscopy in biology. J Microsc 254:109–114. https://doi.org/10.1111/jmi.12127

    Article  CAS  PubMed  Google Scholar 

  61. Burel A, Lavault M-T, Chevalier C et al (2018) A targeted 3D EM and correlative microscopy method using SEM array tomography. Development 145:dev160879. https://doi.org/10.1242/dev.160879

    Article  CAS  PubMed  Google Scholar 

  62. Denk W, Horstmann H (2004) Serial block-face scanning electron microscopy to reconstruct three-dimensional tissue nanostructure. PLoS Biol 2:e329. https://doi.org/10.1371/journal.pbio.0020329

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  63. Rosier DJD, Klug A (1968) Reconstruction of three dimensional structures from electron micrographs. Nature 217:130–134. https://doi.org/10.1038/217130a0

    Article  PubMed  Google Scholar 

  64. Wacker I, Schroeder RR (2013) Array tomography. J Microsc 252:93–99. https://doi.org/10.1111/jmi.12087

    Article  CAS  PubMed  Google Scholar 

  65. White JG, Southgate E, Thomson JN, Brenner S (1986) The structure of the nervous system of the nematode Caenorhabditis elegans. Philos Trans R Soc Lond Ser B Biol Sci 314:1–340. https://doi.org/10.1098/rstb.1986.0056

    Article  CAS  Google Scholar 

  66. Peddie CJ, Collinson LM (2014) Exploring the third dimension: volume electron microscopy comes of age. Micron Oxf Engl 61:9–19. https://doi.org/10.1016/j.micron.2014.01.009

    Article  Google Scholar 

  67. Kremer JR, Mastronarde DN, McIntosh JR (1996) Computer visualization of three-dimensional image data using IMOD. J Struct Biol 116:71–76. https://doi.org/10.1006/jsbi.1996.0013

    Article  CAS  PubMed  Google Scholar 

  68. Mastronarde DN (2008) Correction for non-perpendicularity of beam and tilt axis in tomographic reconstructions with the IMOD package. J Microsc 230:212–217. https://doi.org/10.1111/j.1365-2818.2008.01977.x

    Article  CAS  PubMed  Google Scholar 

  69. Hohmann-Marriott MF, Sousa AA, Azari AA et al (2009) Nanoscale 3D cellular imaging by axial scanning transmission electron tomography. Nat Methods 6:729–731. https://doi.org/10.1038/nmeth.1367

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jens von Einem .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2021 Springer Science+Business Media, LLC, part of Springer Nature

About this protocol

Check for updates. Verify currency and authenticity via CrossMark

Cite this protocol

Read, C., Walther, P., von Einem, J. (2021). Quantitative Electron Microscopy to Study HCMV Morphogenesis. In: Yurochko, A.D. (eds) Human Cytomegaloviruses. Methods in Molecular Biology, vol 2244. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-1111-1_14

Download citation

  • DOI: https://doi.org/10.1007/978-1-0716-1111-1_14

  • Published:

  • Publisher Name: Humana, New York, NY

  • Print ISBN: 978-1-0716-1110-4

  • Online ISBN: 978-1-0716-1111-1

  • eBook Packages: Springer Protocols

Publish with us

Policies and ethics