Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jul 6;13(3):185-196.
doi: 10.1093/jmcb/mjab003.

Kidney injury molecule-1 is a potential receptor for SARS-CoV-2

Chen Yang  1 , Yu Zhang  1 , Xia Zeng  1 , Huijing Chen  1 , Yuchen Chen  1 , Dong Yang  1 , Ziwei Shen  1 , Xiaomu Wang  1 , Xinran Liu  1 , Mingrui Xiong  1 , Hong Chen  1 , Kun Huang  1   2
Affiliations

Kidney injury molecule-1 is a potential receptor for SARS-CoV-2

Chen Yang et al. J Mol Cell Biol. .

Abstract

COVID-19 patients present high incidence of kidney abnormalities, which are associated with poor prognosis and mortality. The identification of SARS-CoV-2 in the kidney of COVID-19 patients suggests renal tropism of SARS-CoV-2. However, whether there is a specific target of SARS-CoV-2 in the kidney remains unclear. Herein, by using in silico simulation, coimmunoprecipitation, fluorescence resonance energy transfer, fluorescein isothiocyanate labeling, and rational design of antagonist peptides, we demonstrate that kidney injury molecule-1 (KIM1), a molecule dramatically upregulated upon kidney injury, binds with the receptor-binding domain (RBD) of SARS-CoV-2 and facilitates its attachment to cell membrane, with the immunoglobulin variable Ig-like (Ig V) domain of KIM1 playing a key role in this recognition. The interaction between SARS-CoV-2 RBD and KIM1 is potently blockaded by a rationally designed KIM1-derived polypeptide AP2. In addition, our results also suggest interactions between KIM1 Ig V domain and the RBDs of SARS-CoV and MERS-CoV, pathogens of two severe infectious respiratory diseases. Together, these findings suggest KIM1 as a novel receptor for SARS-CoV-2 and other coronaviruses. We propose that KIM1 may thus mediate and exacerbate the renal infection of SARS-CoV-2 in a 'vicious cycle', and KIM1 could be further explored as a therapeutic target.

Keywords: COVID-19; SARS-CoV-2; coronavirus; kidney diseases; kidney injury molecule-1.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Basic information of SARS-CoV-2-S and KIM1. (A) Structural scheme of SARS-CoV-2-S. NTD, N-terminal domain; RBM, receptor-binding motif; SD1, subdomain 1; SD2, subdomain 2; FP, fusion peptide; HR1, heptad repeat 1; HR2, heptad repeat 2; TM, transmembrane region; IC, intracellular domain. The domain boundaries of TM and IC have not been precisely defined, and thus the residues are not labeled. (B) Sequence alignment of SARS-CoV-RBD, SARS-CoV-2-RBD, and MERS-CoV-RBD. ACE2-contacting residues of SARS-CoV-RBD and SARS-CoV-2-RBD are highlight in yellow; KIM1-contacting residues of SARS-CoV-RBD are in green; KIM1-contcacting residues of SARS-CoV-RBD-2 are in blue; asterisks indicate fully conserved residues; colons indicate partly conserved residues; periods indicate weakly conserved residues. (C) Relative mRNA levels of Ace2 and Kim1 from the kidneys of I/R- and cisplatin-induced kidney injury mouse models. *P < 0.05, **P < 0.01; ns, no significance. (D and E) Structural scheme of KIM1 domains, in relation to cell membrane. Signal, signal peptide region; Mucin, mucin-containing domain.
Figure 2
Figure 2
Binding model of SARS-CoV-2-RBD and KIM1 Ig V. (A) Low-energy binding conformations of SARS-CoV-2-RBD binding to KIM1 Ig V. Left panel: the surface model of SARS-CoV-2-RBD. Right panel: high-resolution image of the binding sites, Phe338, Val367, Ser371, Phe374, and Trp436 of SARS-CoV-2-RBD interacting with Leu54, Phe55, Gln58, Trp112, and Phe113 of KIM1 Ig V. (B) Distinct binding regions of KIM1 and ACE2 in SARS-CoV-2-RBD, with KIM1-binding pocket in red and ACE-2 binding pocket in blue. (C) SARS-CoV-RBD and SARS-CoV-2-RBD bind with the same pocket of KIM1 Ig V.
Figure 3
Figure 3
SARS-CoV-2-RBD binds with KIM1 Ig V. (A) Constructs used in co-IP studies. (B) The interaction between overexpressed Flag-tagged spike/RBD and HA-tagged KIM1 in HEK293T cells. The indicated plasmids were cotransfected into HEK293T (1 × 107). After 24 h, cells were lysed and subjected to co-IP followed by immunoblotting with indicated antibodies. (C) The interaction between KIM1 Ig V domain and SARS-CoV-2-RBD in KIM1 knockout HK-2 cells. For IP group, KIM1 and KIM1 Ig V domain were detected by anti-KIM1 antibody. Mammalian expression plasmids encoding Flag-tagged spike/RBD were transfected to KIM1 knockout HK-2 cells (1 × 107). After 36 h, cells were lysed and subjected to co-IP followed by immunoblotting with indicated antibodies. Anti-rabbit light chain-specific IgG was used to avoid interference of IgG heavy chain. (D) The interaction between KIM1 Ig V domain and SARS-CoV-2-RBD in HEK293T cells. The experiments were performed as in B except that mammalian expression plasmids encoding HA-tagged KIM1, KIM1 Ig V domain, and truncated KIM1 without Ig V domain (ΔIg V) were used. Anti-rabbit light chain-specific IgG was used to avoid interference of IgG heavy chain. (E) FRET signals of KIM1 and SARS-CoV-2-RBD detected by confocal microscopy. Unconjugated CFP and YFP were cotransfected as the negative control, and the interaction between KIM1 and its ligand TIM4 was included as a positive control. CFP channel: 435/485 nm, excitation/emission; YFP channel: 485/527 nm, excitation/emission; FRET channel: 435/527 nm, excitation/emission. Scale bar, 1.5 μm. (F‒I) Detection of FRET signals using fluorescent wavelength scan for unconjugated CFP and YFP (F), KIM1-CFP and TIM4-YFP (G), KIM1-CFP and SARS-CoV-2-RBD-YFP (H), and KIM1 ΔIg V-CFP and SARS-CoV-2-RBD-YFP (I). (J) Quantitative FRET intensity of the indicated four groups. *P < 0.05, **P < 0.01; ns, no significance.
Figure 4
Figure 4
KIM1 mediates the cell entry of SARS-CoV-2-RBD. (A) Representative images and quantitative data of cell surface attachment of SARS-CoV-2-RBD in wild-type (WT) and KIM1 knockout (KIM1-KO) HK-2 cells. Scale bar, 20 μm. ***P < 0.001. (B) Representative images and quantitative data of cell surface attachment of SARS-CoV-2-RBD in HEK293T cells. Scale bar, 20 μm. OE KIM1, overexpression of KIM1. **P < 0.01.
Figure 5
Figure 5
Rationally designed AP2 inhibits the cell entry of SARS-CoV-2. (A) Schematic diagram of AP1 and AP2. (B) Effects of AP1 and AP2 on the cell attachment of SARS-CoV-2-RBD. Scale bar, 20 μm. (C) Quantitative analysis of the cell attachment of SARS-CoV-2-RBD upon administration of AP1 and AP2. *P < 0.05; ns, no significance. (D) Protective effects of AP2 against SARS-CoV-2-RBD. **P < 0.01; ###P < 0.001 compared to RBD + 10 μM AP2 group; ns, no significance. (E) FRET signal between KIM1 and SARS-CoV-2-RBD in the presence or absence of AP1 and AP2. (F) Quantitative FRET intensity of KIM1-CFP and SARS-CoV-2-RBD-YFP in the presence of AP1 and AP2. *P < 0.05, **P < 0.01; ns, no significance. (G) A proposed working model of ‘a vicious cycle’ comediated by KIM1 and ACE2 in the kidney of COVID-19 patients. KIM1/ACE2 mediate the initial kidney infection, and the resulting AKI drastically upregulates KIM1, which in turn promotes infection and consequently exacerbates the kidney injury. KIM1-derived antagonist peptide may competitively bind with SARS-CoV-2-RBD to intervene viral invasion.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Braun F., Lütgehetmann M., Pfefferle S., et al. (2020). SARS-CoV-2 renal tropism associates with acute kidney injury. Lancet 396, 597–598. - PMC - PubMed
    1. Cha M.H., Regueiro M., Sandhu D.S. (2020). Gastrointestinal and hepatic manifestations of COVID-19: a comprehensive review. World J. Gastroenterol. 26, 2323–2332. - PMC - PubMed
    1. Chen H., Wan D.Y., Wang L., et al. (2015). Apelin protects against acute renal injury by inhibiting TGF-β1. Biochim. Biophys. Acta 1852, 1278–1287. - PubMed
    1. Chen H., Wang L., Wang W., et al. (2017). ELABELA and an ELABELA fragment protect against AKI. J. Am. Soc. Nephrol. 28, 2694–2707. - PMC - PubMed
    1. Chen Y., Yang D., Cheng B., et al. (2020). Clinical characteristics and outcomes of patients with diabetes and COVID-19 in association with glucose-lowering medication. Diabetes Care 43, 1399–1407. - PubMed

Publication types

Substances