Tzviya Zeev-Ben-Mordehai, Marion Weberruß, Michael Lorenz, Juliana Cheleski, Teresa Hellberg, Cathy Whittle, Kamel El Omari, Daven Vasishtan, Kyle C. Dent, Karl Harlos, Christoph Hagen, Barbara G. Klupp, Wolfram Antonin (*), Thomas C. Mettenleiter, and Kay Grünewald (2015) (*)
(*) co-corresponding authors
Cell Reports, 13(12):2645-52. doi: 10.1016/j.celrep.2015.11.008.
While nucleo-cytoplasmic transport is typically mediated through nuclear pore complexes, herpesvirus capsids exit the nucleus via a unique vesicular pathway. The conserved herpesvirus proteins pUL31 and pUL34 together form the heterodimeric nuclear egress complex (NEC), which in turn forms tight fitting membrane vesicles around capsids at the inner nuclear membrane. Here we present the crystal structure of the pseudorabies virus NEC. The structure revealed that a zinc finger motif in pUL31 and an extensive interaction network between the two proteins stabilize the complex. Comprehensive mutational analyses, characterized both in situ and in vitro, indicated that the interaction network is not redundant but rather complementary. Fitting of the NEC crystal structure into the recently determined cryoEM-derived hexagonal lattice,
formed in situ by pUL31 and pUL34, provided details on the molecular basis of NEC coat formation and inner nuclear membrane remodelling.