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Mouse cytomegalovirus egress protein pM50 interacts with cellular endophilin-A2

Frederic Lemnitzer1, Verena Raschbichler, Dominika Kolodziejczak

  • 1Max von Pettenkofer-Institut, Ludwig-Maximilians-Universität München, Pettenkoferstr. 9a, 80336 Munich, Germany.

Cellular Microbiology
|November 30, 2012
PubMed

Insights

Herpesvirus capsid transport relies on nuclear envelopment proteins UL34 and UL31. Researchers identified endophilin-A2 as a key cellular partner interacting with murine cytomegalovirus protein pM50, aiding herpesvirus replication.

Area of Science:

  • Virology
  • Molecular and Cell Biology
  • Protein-Protein Interactions

Background:

  • Herpesvirus replication involves nuclear and cytoplasmic maturation stages.
  • Viral capsids move from the nucleus to the cytoplasm via primary envelopment.
  • This process is mediated by the nuclear envelopment complex, comprising UL34 and UL31 protein families.

Purpose of the Study:

  • To investigate the protein interactions of murine cytomegalovirus (MCMV) UL34 (pM50) and UL31 (pM53) homologues.
  • To identify cellular partners involved in the herpesvirus nuclear-cytoplasmic translocation.
  • To elucidate the role of specific protein interactions in viral replication.

Main Methods:

  • Generation of recombinant MCMV expressing affinity-tagged pM50 and/or pM53.
  • Affinity purification of pM50- and pM53-associated protein complexes from infected cells.
  • Mass spectrometry-based proteomic analysis to identify protein compositions.

Main Results:

  • Identification of previously known and novel protein-protein interactions for pM50 and pM53.
  • Endophilin-A2 identified as a prominent cellular partner interacting with pM50.
  • Direct binding of endophilin-A2 to pM50 demonstrated, suggesting conserved interaction within the UL34 family.

Conclusions:

  • The study reveals new insights into the molecular machinery governing herpesvirus capsid nuclear-cytoplasmic transport.
  • Endophilin-A2 plays a significant role as a cellular interaction partner for MCMV pM50.
  • The identified interaction between endophilin-A2 and pM50 may be conserved across UL34 family members, highlighting a common mechanism in herpesvirus replication.

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