Crystal Structure of the PX Domain of SNX27

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Y. Li^1,a, S. Liao^1,b, F. Li^1,c, and Z. Zhu^1,d*

¹Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, 230027 Hefei, China

^* To whom correspondence should be addressed.

Received July 5, 2018; Revised September 29, 2018; Accepted September 29, 2018

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SNX27 is a component of the retromer complex essential for the recycling of transmembrane receptors. SNX27 contains the N-terminal Phox (PX) domain that binds inositol 1,3-diphosphate (Ins(1,3)P₂) and is important for the SNX27 localization. Here, we determined the crystal structure of human SNX27 PX domain by X-ray crystallography. We found that the sulfate ion is located in the positively charged lipid-binding pocket of the PX domain, which mimics the phospholipid recognition. In addition, we modelled the SNX27-PX–Ins(1,3)P₂ complex to better understand the mechanism of Ins(1,3)P₂ recognition by the PX domain of SNX27.

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KEY WORDS: SNX27, lipid binding, PX domain, crystal structure

DOI: 10.1134/S0006297919020056

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