Citation

  • Authors: Delos, M., Hellec, C., Foulquier, F., Carpentier, M., Allain, F., Denys, A.
  • Year: 2017
  • Journal: FEBS Open Bio 7 133-148
  • Applications: in vitro / siRNA / INTERFERin
  • Cell type: Macrophages

Abstract

Heparan sulfates (HS) are involved in numerous biological processes, which rely on their ability to interact with a large panel of proteins. Although the reaction of 3-O-sulfation can be catalysed by the largest family of HS sulfotransferases, very few mechanisms have been associated with this modification and to date, only glycoprotein D (gD) of herpes simplex virus-1 (HSV-1 gD) and cyclophilin B (CyPB) have been well-described as ligands for 3-O-sulfated HS. Here, we hypothesized that both ligands could induce the same responses via a mechanism dependent on 3-O-sulfated HS. First, we checked that HSV-1 gD was as efficient as CyPB to induce the activation of the same signalling events in primary macrophages. We then demonstrated that both ligands efficiently reduced staurosporin-induced apoptosis and modulated the expression of apoptotic genes. In addition to 3-O-sulfated HS, HSV-1 gD was reported to interact with other receptors, including herpes virus entry mediator (HVEM), nectin-1 and -2. Thus, we decided to identify the contribution of each binding site in the responses triggered by HSV-1 gD and CyPB. We found that knock-down of 3-O-sulfotransferase 2, which is the main 3-O-sulfated HS-generating enzyme in macrophages, strongly reduced the responses induced by both ligands. Moreover, silencing the expression of HVEM rendered macrophages unresponsive to either HSV-1 gD and CyPB, thus indicating that both proteins induced the same responses by interacting with a complex formed by 3-O-sulfated HS and HVEM. Collectively, our results suggest that HSV-1 might hijack the binding sites for CyPB in order to protect macrophages against apoptosis for efficient infection.

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