Structural analysis of herpes simplex virus by optical super-resolution imaging

Laine, Romain F.; Albecka, Anna; van de Linde, Sebastian; Rees, Eric J.; Crump, Colin M.; Kaminski, Clemens F.

Traditionally, fluorescence-based studies of HSV-1 structure have been limited by the small size of the viral particles. Here we used dSTORM super-resolution microscopy to investigate and quantify the organization of key proteins within HSV-1 virions. Our results provide intriguing details on tegument architecture in mature HSV-1 virions that are not accessible to traditional EM or ET techniques. Our work establishes dSTORM as a powerful new tool in deciphering virus structure. First, we conjugated a number of antibodies with dSTORMcompatible organic dyes and optimized labelling protocols to minimize background from nonspecific antibody binding. With two-colour dSTORM, we were able to visualize and discriminate between tegument and envelope protein layers within single virus particles. The organization of important tegument and envelope proteins could then be observed both in purified viruses and in infected cells. The method thus shows great potential as a structural tool to study the organization and interaction of viral and cellular proteins during various stages of virus replication.