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We are deeply saddened by the passing of Amos Bairoch (1957–2025), the creator of PROSITE. We wish to dedicate our latest paper, published shortly before his death, to him. He will always be a source of inspiration to us.
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Amos Bairoch

PROSITE documentation PDOC51923
Coronavirus spike (S) glycoprotein S2 subunit heptad repeat 1 (HR1) and 2 (HR2) regions profiles


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PURL: https://purl.expasy.org/prosite/documentation/PDOC51923

Description

Coronaviruses (CoVs) [E1] are a diverse group of enveloped, plus-stranded RNA viruses that infect humans and many animal species, in which they can cause respiratory, enteric, hepatic, central nervous system and neurological diseases of varying severity. A CoV contains four structural proteins, including spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins. Among them, the S protein, which is located on the envelope surface of the virion, functions to mediate receptor recognition and membrane fusion and is therefore a key factor determining the virus tropism for a specific species. This protein is composed of an N-terminal receptor-binding domain (S1) and a C-terminal trans-membrane fusion domain (S2) [1,2,3].

The S2 subunit contains two 4-3 heptad repeats (HRs) of hydrophobic residues, HR1 and HR2, typical of coiled coils, separated by an ~170-aa-long intervening domain. The S2 subunit is expected to present rearrangement of its HRs to form a stable 6-helix bundle fusion core [1,2,3].

HR1 forms a 24-turn α-helix, while HR2 adopts a mixed conformation: the central part fold into a nine-turn α-helix, while the residues on either side of the helix adopt an extended conformation. The HR1 region forms a long trimeric helical coiled-coil structure with peptides from the HR2 region packing in an oblique antiparallel manner on the grooves of the HR1 trimer in a mixed extended and helical conformation (see <PDB:2BEZ>). Packing of the helical parts of HR2 on the HR1 trimer grooves and formation of a six-helical bundle plays an important role in the formation of a stable post-fusion structure. In contrast to their extended helical conformations in the post-fusion state, the HR1 motifs within S2 form several shorter helices in their pre-fusion state [1,2,3].

The profiles we developed cover the entire CoV S2-HR1 -HR2 regions.

Last update:

April 2020 / First entry.

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Technical section

PROSITE methods (with tools and information) covered by this documentation:

COV_S2_HR1, PS51923; Coronavirus spike (S) glycoprotein S2 subunit heptad repeat 1 (HR1) region profile  (MATRIX)

COV_S2_HR2, PS51924; Coronavirus spike (S) glycoprotein S2 subunit heptad repeat 2 (HR2) region profile  (MATRIX)


References

1AuthorsSupekar V.M. Bruckmann C. Ingallinella P. Bianchi E. Pessi A. Carfi A.
TitleStructure of a proteolytically resistant core from the severe acute respiratory syndrome coronavirus S2 fusion protein.
SourceProc. Natl. Acad. Sci. U. S. A. 101:17958-17963(2004).
PubMed ID15604146
DOI10.1073/pnas.0406128102

2AuthorsZhang W. Zheng Q. Yan M. Chen X. Yang H. Zhou W. Rao Z.
TitleStructural characterization of the HCoV-229E fusion core.
SourceBiochem. Biophys. Res. Commun. 497:705-712(2018).
PubMed ID29458023
DOI10.1016/j.bbrc.2018.02.136

3AuthorsYan L. Meng B. Xiang J. Wilson I.A. Yang B.
TitleCrystal structure of the post-fusion core of the Human coronavirus 229E spike protein at 1.86 angstroem resolution.
SourceActa Crystallogr. D. Struct. Biol. 74:841-851(2018).
PubMed ID30198895
DOI10.1107/S2059798318008318

E1Titlehttps://viralzone.expasy.org/30?outline=all_by_species



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