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The capsid and tegument of the alphaherpesviruses are linked by an interaction between the UL25 and VP1/2 proteins.

ABSTRACT: How alphaherpesvirus capsids acquire tegument proteins remains a key question in viral assembly. Using pseudorabies virus (PRV), we have previously shown that the 62 carboxy-terminal amino acids of the VP1/2 large tegument protein are essential for viral propagation and when transiently expressed as a fusion to green fluorescent protein relocalize to nuclear capsid assemblons following viral infection. Here, we show that localization of the VP1/2 capsid-binding domain (VP1/2cbd) into assemblons is conserved in herpes simplex virus type 1 (HSV-1) and that this recruitment is specifically on capsids. Using a mutant virus screen, we find that the protein product of the UL25 gene is essential for VP1/2cbd association with capsids. An interaction between UL25 and VP1/2 was corroborated by coimmunoprecipitation from cells transiently expressing either HSV-1 or PRV proteins. Taken together, these findings suggest that the essential function of the VP1/2 carboxy terminus is to anchor the VP1/2 tegument protein to capsids. Furthermore, UL25 encodes a multifunctional capsid protein involved in not only encapsidation, as previously described, but also tegumentation.

SUBMITTER: Coller KE

PROVIDER: S-EPMC2168758 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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The capsid and tegument of the alphaherpesviruses are linked by an interaction between the UL25 and VP1/2 proteins.

Coller Kelly Elizabeth KE Lee Joy I-Hsuan JI Ueda Aki A Smith Gregory Allan GA

Journal of virology 20070822 21

How alphaherpesvirus capsids acquire tegument proteins remains a key question in viral assembly. Using pseudorabies virus (PRV), we have previously shown that the 62 carboxy-terminal amino acids of the VP1/2 large tegument protein are essential for viral propagation and when transiently expressed as a fusion to green fluorescent protein relocalize to nuclear capsid assemblons following viral infection. Here, we show that localization of the VP1/2 capsid-binding domain (VP1/2cbd) into assemblons ...[more]

PMID: 17715218

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Dataset Information

The capsid and tegument of the alphaherpesviruses are linked by an interaction between the UL25 and VP1/2 proteins.

Publications

The capsid and tegument of the alphaherpesviruses are linked by an interaction between the UL25 and VP1/2 proteins.

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