Proteome profiling of polyomavirus nuclear replication centers using iPOND

Area of Science:

• Virology
• Molecular Biology
• Cellular Biology

Background:

• Polyomaviruses (PyVs) are known to cause various diseases in mammals.
• PyVs rely on host nuclear factors for viral genome replication and transcription.
• The complete set of viral and host proteins involved in PyV replication, known as the replisome, is not fully understood.

Purpose of the Study:

• To identify host proteins that bind to murine polyomavirus (MuPyV) DNA during and after synthesis.
• To differentiate host factors critical for MuPyV DNA replication versus those involved in later processing stages.

Main Methods:

• Utilized the Isolation of Proteins on Nascent DNA coupled with Mass Spectrometry (iPOND-MS) technique.
• Analyzed proteins bound to MuPyV DNA immediately after synthesis and at 2 hours post-synthesis.

Main Results:

• Identified novel MuPyV DNA interactors on newly synthesized viral DNA (vDNA), including MCM complex members, DNA primase, DNA polymerase alpha, DNA ligase, and replication factor C.
• Observed that host and viral proteins bound to MuPyV DNA at 2 hours post-synthesis differed from those on newly synthesized vDNA, with a lack of many replication proteins.

Conclusions:

• The study distinguishes between host factors essential for MuPyV DNA replication and those involved in downstream processing.
• Understanding these host-viral interactions may lead to the identification of therapeutic targets to suppress PyV replication.