Soluble expression and complex formation of proteins required for HCMV DNA replication using the SFV expression...

Area of Science:

• Virology
• Molecular Biology
• Biochemistry

Background:

• Human cytomegalovirus (HCMV) DNA replication proteins are crucial for viral propagation.
• Studying these proteins is challenging due to low abundance and poor solubility in conventional expression systems.

Purpose of the Study:

• To develop an efficient expression system for studying HCMV DNA replication proteins.
• To characterize the solubility, complex formation, and enzymatic activity of recombinant HCMV proteins.

Main Methods:

• Utilized the Semliki Forest virus (SFV) expression system for protein production in mammalian cells.
• Assessed protein solubility via ultracentrifugation and immunoprecipitation.
• Analyzed post-translational modification of the IE86 protein using pulse-chase assays.
• Investigated complex formation among recombinant viral proteins.
• Tested the activity of the recombinant DNA polymerase holoenzyme.

Main Results:

• Recombinant HCMV proteins were soluble and could be immunoprecipitated.
• Pulse-chase analysis confirmed post-translational processing of the IE86 protein.
• Recombinant proteins formed stable complexes, mimicking those in infected cells.
• The recombinant DNA polymerase holoenzyme displayed phosphonoformic acid-sensitive activity.

Conclusions:

• The SFV expression system is advantageous for producing soluble, active HCMV replication proteins.
• This system facilitates the study of protein interactions and complex formation.
• The SFV system enables the construction and evaluation of viral mutants for further research.