Heat Shock Protein Member 8 Is an Attachment Factor for Infectious Bronchitis Virus

Abstract

Although infectious bronchitis virus (IBV) is the first coronavirus identified, little is known about which membrane protein of host cells could interact with IBV spike protein and facilitate the infection by the virus. In this study, by using a monoclonal antibody to the S1 protein of IBV M41 strain, we found that heat shock protein member 8 (HSPA8) could interact with spike protein of IBV. HSPA8 was found to be present on the cell membrane and chicken tissues, with highest expression level in the kidney. Results of co-IP and GST-pull-down assays indicated that the receptor binding domain (RBD) of IBV M41 could interact with HSPA8. The results of binding blocking assay and infection inhibition assay showed that recombinant protein HSPA8 and antibody to HSPA8 could inhibit IBV M41 infection of chicken embryonic kidney (CEK) cells. Further, we found that HSPA8 interacted with the N-terminal 19–272 amino acids of S1 of IBV Beaudette, H120 and QX strains and HSPA8 from human and pig also interacted with IBV M41-RBD. Finally the results of binding blocking assay and infection inhibition assay showed that recombinant HSPA8 protein and antibody to HSPA8 could inhibit IBV Beaudette strain infection of Vero cells that were treated with heparanase to remove heparan sulfate from the cell surface. Taken together, our results indicate that HSPA8 is a novel host factor involved in IBV infection.

Anticancer Properties and Mechanism of Action of Oblongifolin C, Guttiferone K and Related Polyprenylated Acylphloroglucinols

“…Ob-C binds tightly to this chaperone protein [ 86 ] and our modeling analysis suggests that Gt-K could be an even better HSPA8 binder than Ob-C. On the one hand, this information brings new ideas for the potential use of the natural products in different pathologies, taking advantage of the multiple functions of HSPA8 in cancer and in autoimmune diseases, as mentioned above [ 90 ]. HSPA8 is also a host factor involved in infectious bronchitis virus (IBV, a coronavirus) infection [ 102 ]. HSPA8 is a regulator of the life cycle of the enterovirus A71 (EV-A71) [ 103 ] and Ob-M can potently inhibit the reproduction of this virus [ 104 ].…”

Establishment of Human-Induced Pluripotent Stem Cell-Derived Neurons—A Promising In Vitro Model for a Molecular Study of Rabies Virus and Host Interaction

“…For example, the interaction of HSPA8 with protein X of Bornavirus [ 86 ] or adenoviral hexon protein results in nuclear localization of proteins required for virus growth [ 86 , 87 ]. HSPA8 localized to the cell membrane interacts with the spike protein of the infectious bronchitis virus and facilitates virus infectivity [ 88 ]. These findings suggest the important roles of HSPA8 in multiple phases of the viral life cycle.…”

Known Cellular and Receptor Interactions of Animal and Human Coronaviruses: A Review

“…Infectious bronchitis virus (IBV) has been reported to use HSPs as attachment factors. Specifically, HSP Member 8 (HSPA8) [224], HSP47 [225] and HSP70 [226]. HSP47 was found to interact specifically with the IBV S1 protein [225], after a chicken kidney cDNA library was screened using a yeast two-hybrid system assay.…”