Investigation of herpes simplex virus type 1 genes encoding multiply inserted membrane proteins

Area of Science:

• Virology
• Molecular Biology
• Genetics

Background:

• The herpes simplex virus type 1 (HSV-1) genome encodes four hydrophobic proteins (UL10, UL20, UL43, UL53) with potential membrane-spanning functions.
• These viral proteins have not been previously identified or characterized.

Purpose of the Study:

• To investigate the function of HSV-1 genes UL10, UL20, UL43, and UL53 in the viral life cycle.
• To determine if these genes are essential for HSV-1 replication.

Main Methods:

• Insertion of the Escherichia coli lacZ gene into the open reading frames (ORFs) of HSV-1 genes to create insertion mutants.
• Isolation and characterization of UL10 and UL43 insertion/deletion mutants.
• Assessment of viral growth in tissue culture and in vivo (mouse ear model).
• Detection of viral protein products using antipeptide sera.

Main Results:

• UL10-lacZ insertion mutants exhibited slightly impaired growth in tissue culture compared to wild-type HSV-1.
• UL43 insertion and deletion mutants showed growth indistinguishable from wild-type HSV-1 in tissue culture.
• UL43 deletion mutants replicated effectively in vivo and spread to the nervous system in a mouse ear model.
• Attempts to create lacZ insertion mutants for UL20 and UL53 were unsuccessful, suggesting these genes are essential for viral growth in tissue culture.
• The protein products of genes UL10 and UL20 were detected using antipeptide sera.

Conclusions:

• Gene UL10 plays a role in HSV-1 replication, potentially affecting viral growth.
• Gene UL43 is not essential for HSV-1 replication in vitro or in vivo.
• Genes UL20 and UL53 appear to be essential for HSV-1 replication in tissue culture.
• The protein products of UL10 and UL20 have been identified, contributing to the understanding of HSV-1 molecular biology.