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bioRxiv · 10.1101/2022.05.17.490364

Enhancement of Cell Adhesion by Anaplasma phagocytophilum Nucleolin-interacting Protein AFAP

Tang, H.·Zhu, J.·Wu, S.·Niu, H.
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Abstract

Anaplasma phagocytophilum, the aetiologic agent of human granulocytic anaplasmosis (HGA) is an obligate intracellular Gram-negative bacterium. During infection, A. phagocytophilum enhances the adhesion of neutrophils to infected endothelial cells. However the bacterial factors contributing to this phenomenon remain unknown. In this study, we characterized a type IV secretion system substrate of A. phagocytophilum, AFAP (an actin filament-associated Anaplasma phagocytophilum protein), and found it enhanced cell adhesion. Tandem affinity purification combined with mass spectrometry identified host nucleolin as an AFAP-binding protein. Further study showed disruption of nucleolin by RNA interference and treatment of a nucleolin-binding DNA aptamer AS1411 attenuated AFAP-mediated cell adhesion. The characterization of AFAP with enhancement effect on cell adhesion and identification of its interaction partner may help understand the mechanism underlying A. phagocytophilum-promoting cell adhesion, facilitating elucidation of HGA pathogenesis. HighlightsO_LIAnaplasma phagocytophilum AFAP localized to cell periphery. C_LIO_LIAFAP enhanced cell adhesion. C_LIO_LIAFAP interacted with host nucleolin. C_LIO_LIDisruption of nucleolin attenuated AFAP-mediated cell adhesion. C_LI

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Tang, H., Zhu, J., Wu, S., Niu, H.. 2022-05-17. Enhancement of Cell Adhesion by Anaplasma phagocytophilum Nucleolin-interacting Protein AFAP. https://doi.org/10.1101/2022.05.17.490364

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