Structural features of nectin-2 (HveB) required for herpes simplex virus entry.
One step in the process of herpes simplex virus (HSV) entry into cells is the binding of viral glycoprotein D (gD) to a cellular receptor. Human nectin-2 (also known as HveB and Prr2), a member of the immunoglobulin (Ig) superfamily, serves as a gD receptor for the entry of HSV-2, variant forms of HSV-1 that have amino acid substitutions at position 25 or 27 of gD (for example, HSV-1/Rid), and porcine pseudorabies virus (PRV). The gD binding region of nectin-2 is believed to be localized to the N-terminal variable-like (V) Ig domain. In order to identify specific amino acid sequences in nectin-2 that are important for HSV entry activity, chimeric molecules were constructed by exchange of sequences between human nectin-2 and its mouse homolog, mouse nectin-2, which mediates entry of PRV but not HSV-1 or HSV-2. The nectin-2 chimeric molecules were expressed in Chinese hamster ovary cells, which normally lack a gD receptor, and tested for cell surface expression and viral entry activity. As expected, chimeric molecules containing the V domain of human nectin-2 exhibited HSV entry activity. Replacement of either of two small regions in the V domain of mouse nectin-2 with amino acids from the equivalent positions in human nectin-2 (amino acids 75 to 81 or 89) transferred HSV-1/Rid entry activity to mouse nectin-2. The resulting chimeras also exhibited enhanced HSV-2 entry activity and gained the ability to mediate wild-type HSV-1 entry. Replacement of amino acid 89 of human nectin-2 with the corresponding mouse amino acid (M89F) eliminated HSV entry activity. These results identify two different amino acid sequences, predicted to lie adjacent to the C' and C" beta-strands of the V domain, that are critical for HSV entry activity. This region is homologous to the human immunodeficiency virus binding region of CD4 and to the poliovirus binding region of CD155.
Martinez
W M
WM
Department of Microbiology-Immunology, Northwestern University Medical School, Chicago, Illinois 60611, USA.
Spear
P G
PG
D000595:Amino Acid Sequence; D000818:Animals; D015815:Cell Adhesion Molecules / Q000737:chemistry* / Q000502:physiology; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D000075983:Nectins; D011991:Receptors, Virus / Q000737:chemistry / Q000502:physiology; D018139:Simplexvirus / Q000502:physiology*; D013045:Species Specificity; D013329:Structure-Activity Relationship
D015815:Cell Adhesion Molecules; C000619016:Nectin2 protein, mouse; D000075983:Nectins; D011991:Receptors, Virus