Interaction between human papillomavirus type 5 E2 and polo-like kinase 1

Area of Science:

• Virology
• Molecular Biology
• Cell Biology

Background:

• The E2 protein is crucial for papillomavirus replication.
• Human polo-like kinase 1 (Plk1) is a key regulator of cell cycle.
• Epidermodysplasia verruciformis-associated human papillomaviruses (HPVs) are linked to skin cancers.

Purpose of the Study:

• To investigate the interaction between human papillomavirus type 5 E2 (HPV-5 E2) and human polo-like kinase 1 (Plk1).
• To elucidate the functional consequences of this interaction on cellular proteins, specifically Brd4.

Main Methods:

• Yeast two-hybrid screening to identify interacting proteins.
• In vitro biochemical assays to characterize protein-protein interactions and phosphorylation.
• In vivo colocalization studies using microscopy.

Main Results:

• HPV-5 E2 directly interacts with Plk1 through specific domains.
• Plk1 and HPV-5 E2 colocalize in nuclear speckles within epithelial cells.
• HPV-5 E2 inhibits Plk1-mediated phosphorylation of Brd4's E2 binding domain.

Conclusions:

• Plk1 and HPV-5 E2 form a complex in infected keratinocytes.
• The interaction between Plk1 and HPV-5 E2 may lead to the de-regulation of Brd4's cellular functions.
• This interaction could contribute to the pathogenesis of HPV-5 infections.