A threonine-based targeting signal in the human CD1d cytoplasmic tail controls its functional expression

Jianyun Liu, Daniel Shaji, Sungyoo Cho, Wenjun Du, Jacquelyn Gervay-Hague, Randy R. Brutkiewicz

Research output: Contribution to journalArticle

21 Scopus citations


CD1d molecules are MHC class I-like molecules that present lipids to a unique subpopulation of T cells called NKT cells. The cytoplasmic tail of human CD1d possesses a tyrosine-based endosomal targeting motif (YXXZ). As such, these molecules traffic through the endocytic pathway, where it is believed that they are loaded with the antigenic lipid that stimulates NKT cells. In the current study, it was found that the T322 residue in the human CD1d tail is a major signal controlling transport to the cell surface and thus its functional expression. Mimicking the phosphorylation of this residue or removal of the entire cytoplasmic tail negates its ability to regulate CD1d trafficking, resulting in lysosomal targeting and degradation. These results demonstrate an important role of a heretofore unknown signal in the cytoplasmic tail of CD1d that may have relevance to other type I integral membrane proteins that traverse through the endocytic pathway.

Original languageEnglish (US)
Pages (from-to)4973-4981
Number of pages9
JournalJournal of Immunology
Issue number9
StatePublished - May 1 2010


ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

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