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.

In addition, our data demonstrate that the spatial distribution of tegument proteins within a virion cannot necessarily be inferred from the stability of their attachment to the capsid. pUL37 is commonly defined as an inner tegument protein, partly due to its interaction with VP1/2 (ref. 12 ) and the resistance of both these proteins to removal from purified capsids 51 . Here we have shown that the N-terminal region of pUL37 is located close to VP16 and in proximity to the envelope. Interestingly, pUL37 has recently been shown to interact with the gK/pUL20 envelope protein complex 52 , implying that pUL37 could span the tegument, linking VP1/2 to the envelope. In addition, VP16 is known to interact with the cytoplasmic domains of other envelope glycoproteins 41, 42 . These previous findings support our observations using super-resolution microscopy, which showed that both VP16 and pUL37 are located close to the envelope. It will be important in the future to also determine the spatial distribution of other tegument proteins to complete the model of the architecture of this complex structural domain.