Severe acute respiratory syndrome coronavirus 2 Envelope small membrane protein; This group contains the Envelope (E) small membrane protein of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. There are five essential genes in CoVs that result in the following gene products: Spike (S) protein, Membrane (M) glycoprotein, Nucleocapsid (N), Envelope (E) protein, and the Orf1ab (a large polyprotein known as replicase/protease); all are required to produce a structurally complete viral particle. The E protein is a small polypeptide (76-109 amino acids) that contains a single alpha-helical transmembrane domain. It plays a central role in virus morphogenesis and assembly. It acts as a viroporin and self-assembles in host membranes forming homopentameric protein-lipid pores that allow ion transport with poor selectivity. For some CoVs, such as mouse hepatitis virus (MHV) and SARS-CoV, deletion of the E gene did not completely abolish replication, but the virions were severely disabled from infecting new host cells with significantly reduced viral titers. In animal models, SARS-CoV lacking the E gene also showed significantly attenuated viral titers, likely due to its deficiency in suppressing host stress response and apoptosis induction. Moreover, the PDZ-binding motif (PBM) at the C-terminus of SARS-CoV E protein was shown to interact with a host PDZ protein called syntenin and lead to its relocation from nucleus to cytoplasm during SARS-CoV infection, thereby activating p38 kinase to induce the overexpression of inflammatory cytokines. Thus, the E protein is involved in both, viral replication and pathogenesis during CoV infection.

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gi 30173401  2 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPTVYVYSRVKNLNSSEGVPDLLV 76
Cdd:cd21536  1 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPSFYVYSRVKNLNSSQEVPDLLV 75

Severe acute respiratory syndrome coronavirus 2 Envelope small membrane protein; This group contains the Envelope (E) small membrane protein of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. There are five essential genes in CoVs that result in the following gene products: Spike (S) protein, Membrane (M) glycoprotein, Nucleocapsid (N), Envelope (E) protein, and the Orf1ab (a large polyprotein known as replicase/protease); all are required to produce a structurally complete viral particle. The E protein is a small polypeptide (76-109 amino acids) that contains a single alpha-helical transmembrane domain. It plays a central role in virus morphogenesis and assembly. It acts as a viroporin and self-assembles in host membranes forming homopentameric protein-lipid pores that allow ion transport with poor selectivity. For some CoVs, such as mouse hepatitis virus (MHV) and SARS-CoV, deletion of the E gene did not completely abolish replication, but the virions were severely disabled from infecting new host cells with significantly reduced viral titers. In animal models, SARS-CoV lacking the E gene also showed significantly attenuated viral titers, likely due to its deficiency in suppressing host stress response and apoptosis induction. Moreover, the PDZ-binding motif (PBM) at the C-terminus of SARS-CoV E protein was shown to interact with a host PDZ protein called syntenin and lead to its relocation from nucleus to cytoplasm during SARS-CoV infection, thereby activating p38 kinase to induce the overexpression of inflammatory cytokines. Thus, the E protein is involved in both, viral replication and pathogenesis during CoV infection.

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gi 30173401  2 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPTVYVYSRVKNLNSSEGVPDLLV 76
Cdd:cd21536  1 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPSFYVYSRVKNLNSSQEVPDLLV 75

Severe acute respiratory syndrome coronavirus 2 Envelope small membrane protein; This group contains the Envelope (E) small membrane protein of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. There are five essential genes in CoVs that result in the following gene products: Spike (S) protein, Membrane (M) glycoprotein, Nucleocapsid (N), Envelope (E) protein, and the Orf1ab (a large polyprotein known as replicase/protease); all are required to produce a structurally complete viral particle. The E protein is a small polypeptide (76-109 amino acids) that contains a single alpha-helical transmembrane domain. It plays a central role in virus morphogenesis and assembly. It acts as a viroporin and self-assembles in host membranes forming homopentameric protein-lipid pores that allow ion transport with poor selectivity. For some CoVs, such as mouse hepatitis virus (MHV) and SARS-CoV, deletion of the E gene did not completely abolish replication, but the virions were severely disabled from infecting new host cells with significantly reduced viral titers. In animal models, SARS-CoV lacking the E gene also showed significantly attenuated viral titers, likely due to its deficiency in suppressing host stress response and apoptosis induction. Moreover, the PDZ-binding motif (PBM) at the C-terminus of SARS-CoV E protein was shown to interact with a host PDZ protein called syntenin and lead to its relocation from nucleus to cytoplasm during SARS-CoV infection, thereby activating p38 kinase to induce the overexpression of inflammatory cytokines. Thus, the E protein is involved in both, viral replication and pathogenesis during CoV infection.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 30173401  2 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPTVYVYSRVKNLNSSEGVPDLLV 76
Cdd:cd21536  1 YSFVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPSFYVYSRVKNLNSSQEVPDLLV 75

Coronavirus small envelope protein E; This family includes E proteins, well conserved among Coronavirus strains. They are small, integral membrane proteins involved in several aspects of the virus' life cycle, such as assembly, budding, envelope formation, and pathogenesis. They act as a viroporin by oligomerizing after insertion in host membranes to create a hydrophilic pore that allows ion transport,. SARS-CoV E protein forms a Ca2+ permeable channel in the endoplasmic reticulum Golgi apparatus intermediate compartment (ERGIC)/Golgi membranes. The E protein ion channel activity alters Ca2+ homeostasis within cells boosting the activation of the NLRP3 inflammasome, leading to the overproduction of IL-beta. SARS-CoV overstimulates the NF-kappaB inflammatory pathway, triggering p38 MARK activation.

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gi 30173401    2 YSFVSEETGtLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPTVYVYSRVKNLNSSEGVPDLLV 76
Cdd:pfam02723  1 LLFVINDTG-LVVNIILWLLVCIVVLLVSIAFLTLIKLCFQCCRLCNTLVYSPVIYVYNAYKDYMQIEPLPPVDD 74

Middle East respiratory syndrome-related coronavirus Envelope small membrane protein and similar proteins; This group contains the Envelope (E) small membrane protein of Middle East respiratory syndrome (MERS) coronavirus (CoV), as well as E proteins from related coronaviruses. There are five essential genes in CoVs that result in the following gene products: Spike (S) protein, Membrane (M) glycoprotein, Nucleocapsid (N), Envelope (E) protein, and the Orf1ab (a large polyprotein known as replicase/protease); all are required to produce a structurally complete viral particle. The E protein is a small polypeptide (76-109 amino acids) that contains a single alpha-helical transmembrane domain. It plays a central role in virus morphogenesis and assembly. It acts as a viroporin and self-assembles in host membranes forming homopentameric protein-lipid pores that allow ion transport with poor selectivity. For some CoVs, such as mouse hepatitis virus (MHV) and SARS-CoV, deletion of the E gene did not completely abolish replication, but the virions were severely disabled from infecting new host cells with significantly reduced viral titers. In animal models, SARS-CoV lacking the E gene also showed significantly attenuated viral titers, likely due to its deficiency in suppressing host stress response and apoptosis induction. Moreover, the PDZ-binding motif (PBM) at the C-terminus of SARS-CoV E protein was shown to interact with a host PDZ protein called syntenin and lead to its relocation from nucleus to cytoplasm during SARS-CoV infection, thereby activating p38 kinase to induce the overexpression of inflammatory cytokines. Thus, the E protein is involved in both, viral replication and pathogenesis during CoV infection.

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gi 30173401  4 FVSEETGTLIVNSVLLFLAFVVFLLVTLAILTALRLCAYCCNIVNVSLVKPTVYVY 59
Cdd:cd21533  3 FVQEQIGSFIVNFFIFTVVCAITLLVCMAFLTATRLCVQCATGFNTLLVQPAIYVY 58