title: Cleavage and activation of the severe acute respiratory syndrome coronavirus spike protein by human airway trypsin-like protease.
abstract: The highly pathogenic severe acute respiratory syndrome coronavirus (SARS-CoV) poses a constant threat to human health. The viral spike protein (SARS-S) mediates host cell entry and is a potential target for antiviral intervention. Activation of SARS-S by host cell proteases is essential for SARS-CoV infectivity but remains incompletely understood. Here, we analyzed the role of the type II transmembrane serine proteases (TTSPs) human airway trypsin-like protease (HAT) and transmembrane protease, serine 2 (TMPRSS2), in SARS-S activation. We found that HAT activates SARS-S in the context of surrogate systems and authentic SARS-CoV infection and is coexpressed with the viral receptor angiotensin-converting enzyme 2 (ACE2) in bronchial epithelial cells and pneumocytes. HAT cleaved SARS-S at R667, as determined by mutagenesis and mass spectrometry, and activated SARS-S for cell-cell fusion in cis and trans, while the related pulmonary protease TMPRSS2 cleaved SARS-S at multiple sites and activated SARS-S only in trans. However, TMPRSS2 but not HAT expression rendered SARS-S-driven virus-cell fusion independent of cathepsin activity, indicating that HAT and TMPRSS2 activate SARS-S differentially. Collectively, our results show that HAT cleaves and activates SARS-S and might support viral spread in patients.
authors: Institute of Virology, Hannover Medical School, Hannover, Germany.
authors: Stephanie
authors: S
authors: Bertram
authors: Ilona
authors: I
authors: Glowacka
authors: Marcel A
authors: MA
authors: Müller
authors: Hayley
authors: H
authors: Lavender
authors: Kerstin
authors: K
authors: Gnirss
authors: Inga
authors: I
authors: Nehlmeier
authors: Daniela
authors: D
authors: Niemeyer
authors: Yuxian
authors: Y
authors: He
authors: Graham
authors: G
authors: Simmons
authors: Christian
authors: C
authors: Drosten
authors: Elizabeth J
authors: EJ
authors: Soilleux
authors: Olaf
authors: O
authors: Jahn
authors: Imke
authors: I
authors: Steffen
authors: Stefan
authors: S
authors: Pöhlmann
mesh_terms: D000085962:Angiotensin-Converting Enzyme 2; D002460:Cell Line; D015870:Gene Expression; D054884:Host-Pathogen Interactions; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism*; D007703:Peptidyl-Dipeptidase A / Q000096:biosynthesis; D059748:Proteolysis; D011991:Receptors, Virus / Q000096:biosynthesis; D045473:Severe acute respiratory syndrome-related coronavirus / Q000472:pathogenicity*; D012697:Serine Endopeptidases / Q000378:metabolism*; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D011991:Receptors, Virus; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; D007703:Peptidyl-Dipeptidase A; C000705307:ACE2 protein, human; D000085962:Angiotensin-Converting Enzyme 2; D012697:Serine Endopeptidases; C112256:human airway trypsin-like protease