Disruption of the annexin A1/S100A11 complex increases the migration and clonogenic growth by dysregtilating epithelial growth factor (EGF) signaling

作者：Poeter Michaela; Radke Susanne; Koese Meryem; Hessner Florian; Hegemann Anika; Musiol Agnes; Gerke Volker; Grewal Thomas; Rescher Ursula^*

来源：Biochimica et Biophysica Acta-Molecular Cell Research, 2013, 1833(7): 1700-1711.

DOI：10.1016/j.bbamcr.2012.12.006

• Annexin A1
• S100A11
• Epidermal growth factor receptor
• Endocytosis
• Late endosomes
• MAP kinase signaling

Endocytosis of activated growth factor receptors regulates spatio-temporal cellular signaling. In the case of the EGF receptor, sorting into multivesicular bodies (MVBs) controls signal termination and subsequently leads to receptor degradation in lysosomes. Annexin A1, a ca(2+)-reguIated membrane binding protein often deregulated in human cancers, interacts with the EGF receptor and is phosphorylated by internalized EGF receptor on endosomes. Most relevant for EGF receptor signal termination, annexin A1 is required for the formation of internal vesicles in MVBs that sequester ligand-bound EGF receptor away from the limiting membrane. To elucidate the mechanism underlying annexin A1-dependent EGF receptor trafficking we employed an N-terminally truncated annexin Al mutant that lacks the EGF receptor phosphorylation site and the site for interaction with its protein ligand S100A11. Overexpression of this dominant-negative mutant induces a delay in EGF-induced EGF receptor transport to the LAMP1-positive late endosomal/lysosomal compartment and impairs ligand-induced EGF receptor degradation. Consistent with these findings, EGF-stimulated EGF receptor and MAP kinase pathway signaling is prolonged. Importantly, depletion of S100A11 also results in a delayed EGF receptor transport and prolonged MAP kinase signaling comparable to the trafficking defect observed in cells expressing the N-terminally truncated annexin A1 mutant. These results strongly suggest that the function of annexin A1 as a regulator of EGF receptor trafficking, degradation and signaling is critically mediated through an N-terminal interaction with S100A11 in the endosomal compartment. This interaction appears to be essential for lysosomal targeting of the EGF receptor, possibly by providing a physical scaffold supporting inward vesiculation in MVBs. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.

• 出版日期2013-7
• 单位河北医科大学