DDR1 promotes E-cadherin stability via inhibition of integrin-β1-Src activation-mediated E-cadherin endocytosis.
Discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase of collagen, is primarily expressed in epithelial cells. Activation of DDR1 stabilises E-cadherin located on the cell membrane; however, the detailed mechanism of DDR1-stabilised E-cadherin remains unclear. We performed DDR1 knockdown (Sh-DDR1) on Mardin-Darby canine kidney cells to investigate the mechanism of DDR1-stabilised E-cadherin. Sh-DDR1 decreased junctional localisation, increased endocytosis of E-cadherin, and increased physical interactions between E-cadherin and clathrin. Treatment of the dynamin inhibitor Dyngo 4a suppressed Sh-DDR1-induced E-cadherin endocytosis. In addition, the phosphorylation level of Src tyrosine 418 was increased in Sh-DDR1 cell junctions, and inhibition of Src activity decreased Sh-DDR1-induced E-cadherin endocytosis. To characterise the molecular mechanisms, blocking integrin β1 decreased Src activity and E-cadherin junctional localisation in Sh-DDR1 cells. Photoconversion results showed that inhibition of Src activity rescued E-cadherin membrane stability and that inhibition of integrin β1-Src signalling decreased stress fibres and rescued E-cadherin membrane stability in Sh-DDR1 cells. Taken together, DDR1 stabilised membrane localisation of E-cadherin by inhibiting the integrin β1-Src-mediated clathrin-dependent endocytosis pathway.
Department of Physiology National Cheng Kung University, Tainan, Taiwan.
Hong-Ru
HR
Chen
Department of Physiology National Cheng Kung University, Tainan, Taiwan.
Yi-Chun
YC
Yeh
Department of Physiology National Cheng Kung University, Tainan, Taiwan.|Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan.
Ching-Yi
CY
Liu
Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yu-Ting
YT
Wu
Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Fang-Yu
FY
Lo
Department of Physiology National Cheng Kung University, Tainan, Taiwan.|Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan.
Ming-Jer
MJ
Tang
Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan.|Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yang-Kao
YK
Wang
D000818:Animals; D015703:Antigens, CD; D015820:Cadherins / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000378:metabolism; D000070819:Discoidin Domain Receptor 1 / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D004705:Endocytosis; D055785:Gene Knockdown Techniques; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism*; D007365:Intercellular Junctions / Q000378:metabolism; D061985:Madin Darby Canine Kidney Cells; D055550:Protein Stability; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism*
D015703:Antigens, CD; C513384:CDH1 protein, human; D015820:Cadherins; D002966:Clathrin; D019012:Integrin beta1; C092030:DDR1 protein, human; D000070819:Discoidin Domain Receptor 1; D016392:Proto-Oncogene Proteins pp60(c-src)