論文

査読有り 最終著者 責任著者 国際誌
2020年7月10日

Blood group P1 antigen–bearing glycoproteins are functional but less efficient receptors of Shiga toxin than conventional glycolipid-based receptors

Journal of Biological Chemistry
  • Kanta Morimoto
  • ,
  • Noriko Suzuki
  • ,
  • Isei Tanida
  • ,
  • Soichiro Kakuta
  • ,
  • Yoko Furuta
  • ,
  • Yasuo Uchiyama
  • ,
  • Kentaro Hanada
  • ,
  • Yusuke Suzuki
  • ,
  • Toshiyuki Yamaji

295
28
開始ページ
9490
終了ページ
9501
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1074/jbc.ra120.013926
出版者・発行元
American Society for Biochemistry & Molecular Biology (ASBMB)

Shiga toxin (STx) is a virulence factor produced by enterohemorrhagic <italic>Escherichia coli.</italic> STx is taken up by mammalian host cells by binding to the glycosphingolipid (GSL) globotriaosylceramide (Gb3; Galα1-4Galβ1-4Glc-ceramide) and causes cell death after its retrograde membrane transport. However, the contribution of the hydrophobic portion of Gb3 (ceramide) to STx transport remains unclear. In pigeons, blood group P1 glycan antigens (Galα1-4Galβ1-4GlcNAc-) are expressed on glycoproteins that are synthesized by α1,4-galactosyltransferase 2 (pA4GalT2). To examine whether these glycoproteins can also function as STx receptors, here we constructed glycan-remodeled HeLa cell variants lacking Gb3 expression but instead expressing pA4GalT2-synthesized P1 glycan antigens on glycoproteins. We compared STx binding and sensitivity of these variants with those of the parental, Gb3-expressing HeLa cells. The glycan-remodeled cells bound STx1 via <italic>N</italic>-glycans of glycoproteins and were sensitive to STx1 even without Gb3 expression, indicating that P1-containing glycoproteins also function as STx receptors. However, these variants were significantly less sensitive to STx than the parent cells. Fluorescence microscopy and correlative light EM revealed that the STx1 B subunit accumulates to lower levels in the Golgi apparatus after glycoprotein-mediated than after Gb3-mediated uptake but instead accumulates in vacuole-like structures probably derived from early endosomes. Furthermore, coexpression of Galα1-4Gal on both glycoproteins and GSLs reduced the sensitivity of cells to STx1 compared with those expressing Galα1-4Gal only on GSLs, probably because of competition for STx binding or internalization. We conclude that lipid-based receptors are much more effective in STx retrograde transport and mediate greater STx cytotoxicity than protein-based receptors.

リンク情報
DOI
https://doi.org/10.1074/jbc.ra120.013926
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/32409578
PubMed Central
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7363145
URL
https://syndication.highwire.org/content/doi/10.1074/jbc.RA120.013926
ID情報
  • DOI : 10.1074/jbc.ra120.013926
  • ISSN : 0021-9258
  • eISSN : 1083-351X
  • PubMed ID : 32409578
  • PubMed Central 記事ID : PMC7363145

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