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Role of endocytosis and cathepsin-mediated activation in Nipah virus entry.

ABSTRACT: The recent discovery that the Nipah virus (NiV) fusion protein (F) is activated by endosomal cathepsin L raised the question if NiV utilize pH- and protease-dependent mechanisms of entry. We show here that the NiV receptor ephrin B2, virus-like particles and infectious NiV are internalized from the cell surface. However, endocytosis, acidic pH and cathepsin-mediated cleavage are not necessary for the initiation of infection of new host cells. Our data clearly demonstrate that proteolytic activation of the NiV F protein is required before incorporation into budding virions but not after virus entry.

SUBMITTER: Diederich S

PROVIDER: S-EPMC7103400 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Role of endocytosis and cathepsin-mediated activation in Nipah virus entry.

Diederich Sandra S Thiel Lena L Maisner Andrea A

Virology 20080314 2

The recent discovery that the Nipah virus (NiV) fusion protein (F) is activated by endosomal cathepsin L raised the question if NiV utilize pH- and protease-dependent mechanisms of entry. We show here that the NiV receptor ephrin B2, virus-like particles and infectious NiV are internalized from the cell surface. However, endocytosis, acidic pH and cathepsin-mediated cleavage are not necessary for the initiation of infection of new host cells. Our data clearly demonstrate that proteolytic activat ...[more]

PMID: 18342904

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