Abstract
ErbB-2/HER2 drives epithelial malignancies by forming heterodimers with growth factor receptors. The primordial invertebrate receptor is sorted to the basolateral epithelial surface by binding of the PDZ domain of Lin-7 to the receptor's tail. We show that all four human ErbBs are basolaterally expressed, even when the tail motif is absent. Mutagenesis of hLin-7 unveiled a second domain, KID, that binds to the kinase region of ErbBs. The PDZ interaction mediates stabilization of ErbB-2 at the basolateral surface. On the other hand, binding of KID is involved in initial delivery to the basolateral surface, and in its absence, unprocessed ErbB-2 molecules are diverted to the apical surface. Hence, distinct domains of Lin-7 regulate receptor delivery to and maintenance at the basolateral surface of epithelia.
Original language | English |
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Pages (from-to) | 475-486 |
Number of pages | 12 |
Journal | Developmental Cell |
Volume | 5 |
Issue number | 3 |
DOIs | |
State | Published - 1 Sep 2003 |
Bibliographical note
Funding Information:We thank Drs. Borg and Birnboim for plasmids; Dr. Ena Orzech for advice; and the microscopy unit of the Hebrew University for immunofluorescence. This work was supported in part by grants from the National Cancer Institute (grant CA72981), the European Community (grant QLG1-2000-02160), the United States-Israel Binational Science Foundation (grant 1999-277), and the Israel Science Foundation funded by the Israel Academy of Sciences.