2. Academic Validation
  3. Structure of sorting nexin 11 (SNX11) reveals a novel extended phox homology (PX) domain critical for inhibition of SNX10-induced vacuolation

Structure of sorting nexin 11 (SNX11) reveals a novel extended phox homology (PX) domain critical for inhibition of SNX10-induced vacuolation

  • J Biol Chem. 2013 Jun 7;288(23):16598-16605. doi: 10.1074/jbc.M112.449306.
Jinxin Xu 1,  Tingting Xu 1,  Bin Wu 2,  Yinghua Ye 2,  Xiaojuan You 3,  Xiaodong Shu 2,  Duanqing Pei 2,  Jinsong Liu 4
Affiliations

Affiliations

  • 1 State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530; School of Life Sciences, University of Science and Technology of China, Hefei 230026.
  • 2 Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China.
  • 3 State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530.
  • 4 State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530; School of Life Sciences, University of Science and Technology of China, Hefei 230026. Electronic address: [email protected].
PMID: 23615901 DOI: 10.1074/jbc.M112.449306
Abstract

Sorting nexins are phox homology (PX) domain-containing proteins involved in diverse intracellular endosomal trafficking pathways. The PX domain binds to certain phosphatidylinositols and is recruited to vesicles rich in these lipids. The structure of the PX domain is highly conserved, containing a three-stranded β-sheet, followed by three α-helices. Here, we report the crystal structures of truncated human SNX11 (sorting nexin 11). The structures reveal that SNX11 contains a novel PX domain, hereby named the extended PX (PXe) domain, with two additional α-helices at the C terminus. We demonstrate that these α-helices are indispensible for the in vitro functions of SNX11. We propose that this PXe domain is present in SNX10 and is responsible for the vacuolation activity of SNX10. Thus, this novel PXe domain constitutes a structurally and functionally important PX domain subfamily.

Keywords

Cell Sorting; Endosome; PX Domain; PXe Domain; Phosphatidylinositol; Protein Sorting; Protein Structure; SNX10; SNX11; Sorting.

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