Collaborative project for curation biological processes involved in the COVID-19 disease after SARS-Cov-2 infection. It focuses on experimental evidence and plays with improved annotation of complexes and with the Evidence and Conclusion Ontology. The complexes link to EBI's Complex Portal, resulting from a collaboration with that database at the recent online ELIXIR biohackathon. Editing this pathway is (at this moment) coordinated via the wikipathways.slack.com #sarscov2 channel. Additionally, please feel free to add suggestions to the discussion page (see the tab at the top of this page). The large viral Spike protein (S or surface glycoprotein) forms trimers. It interacts with the host's ACE2 receptor to establish binding (Hoffmann et al 2020). There are suggestions for more than one cell entry mechanism, with the evidence for ACE2/TMPRSS2 entry being most clear now. Lack of expression of TMPRSS2 may explain age differences in COVID19 severity. In this mechanism, to enter the virus needs to be primed by the host protease TMPRSS2 that splits the Spike protein into 2 peptides S1 and S2. S1 contains the ACE2 receptor binding site, S2 binds to the host cell membrane which leads to membrane fusion, the start of the uptake process. The ACE2 receptor interaction was also suggested as the start of specific lung-damaging effects. Other human genes that may be involved in alternative cell uptake mechanisms include CTSL and SLC6A19. [STIMULATION:id912daad6] Invalid interaction type. [LINE:idbb7865a7] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id31b492b0] Invalid interaction type. [LINE:id1f86b6c5] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:ida46f2e34] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:f9791] Invalid interaction type. [LINE:c849c] Invalid interaction type. [LINE:id768dd6a5] Invalid interaction type. [LINE:id7acf7b3] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id95aba954] Invalid interaction type. [LINE:idd6e4d05b] Invalid interaction type. [LINE:id858197a5] Invalid interaction type. [LINE:ide3b4c27b] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id88a323b4] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:ida427ca0] Invalid interaction type. [LINE:id52141a70] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id68553d54] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:f30e4] Invalid interaction type. [LINE:idb8ba3d51] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:idc79adab4] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id9d2699b4] Invalid interaction type. [LINE:id54006fd1] Invalid interaction type. [LINE:idb2e3b478] Invalid interaction type. [LINE:idc71222d4] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:idc3f0c926] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id254c7db4] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id53ccbca1] Invalid interaction type. [LINE:id7a78fc75] Invalid interaction type. [LINE:idd97096a5] Invalid interaction type. [STIMULATION:ide22650b2] Invalid interaction type. [LINE:idff4da966] Invalid interaction type. [TRANSCRIPTION_TRANSLATION:id5c4ff7f0] Invalid interaction type. [INHIBITION:idd58d2076] Interaction can not connect two anchors. [BioPax:e63] No pubmed identifier defined for publication: title: Neuropilin-1 facilitates SARS-CoV-2 cell entry and provides a possible pathway into the central nervous system [BioPax:c4d] No pubmed identifier defined for publication: title: [BioPax:e25] No pubmed identifier defined for publication: title: Preprint: TMPRSS2 and furin are both essential for proteolytic activation and spread of SARS-1 CoV-2 in human airway epithelial cells and provide promising drug targets [BioPax:bbb] No pubmed identifier defined for publication: title: The crystal structure of Nsp9 replicase protein of COVID-19 [BiopaxReference:e63] Publication is invalid. [:a479d] Shape can not be part of reaction. Tranforming to Unknown [HeterodimerAssociationReaction:id8acd3f8f] Reaction should contain at least 2 reactants. GraphId: id8acd3f8f [HeterodimerAssociationReaction:id94e29422] Reaction should contain at least 2 reactants. GraphId: id94e29422 [HeterodimerAssociationReaction:id76a29895] Reaction should contain at least 2 reactants. GraphId: id76a29895 [HeterodimerAssociationReaction:id596b2488] Reaction should contain at least 2 reactants. GraphId: id596b2488 [HeterodimerAssociationReaction:iddb77d7c7] Reaction should contain at least 2 reactants. GraphId: iddb77d7c7 [BiopaxReference:e63] Publication is invalid. [HeterodimerAssociationReaction:idacdc1203] Reaction should contain at least 2 reactants. GraphId: idacdc1203 [HeterodimerAssociationReaction:iddc9f49d1] Reaction should contain at least 2 reactants. GraphId: iddc9f49d1 [-:-] Miriam data (PUBMED: 32944968) for idff4da966 already exists. Ignoring... [Complex:c0fce] Empty element is invalid [Complex:ad905] Empty element is invalid [BiopaxReference:c4d] Publication is invalid.