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bioRxiv · 10.1101/2020.02.17.951848

Structure of dimeric full-length human ACE2 in complex with B0AT1

Zhou, Q.·Yan, R.·Zhang, Y.·Li, Y.·Xia, L.
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Abstract

Angiotensin-converting enzyme 2 (ACE2) is the surface receptor for SARS coronavirus (SARS-CoV), directly interacting with the spike glycoprotein (S protein). ACE2 is also suggested to be the receptor for the new coronavirus (2019-nCoV), which is causing a serious epidemic in China manifested with severe respiratory syndrome. B0AT1 (SLC6A19) is a neutral amino acid transporter whose surface expression in intestinal cells requires ACE2. Here we present the 2.9 [A] resolution cryo-EM structure of full-length human ACE2 in complex with B0AT1. The complex, assembled as a dimer of ACE2-B0AT1 heterodimers, exhibits open and closed conformations due to the shifts of the peptidase domains (PDs) of ACE2. A newly resolved Collectrin-like domain (CLD) on ACE2 mediates homo-dimerization. Structural modelling suggests that the ACE2-B0AT1 complex can bind two S proteins simultaneously, providing important clues to the molecular basis for coronavirus recognition and infection.

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Zhou, Q., Yan, R., Zhang, Y., Li, Y., Xia, L.. 2020-02-18. Structure of dimeric full-length human ACE2 in complex with B0AT1. https://doi.org/10.1101/2020.02.17.951848

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