N-glycosylation affects the adhesive function of E-Cadherin through modifying the composition of adherens junctions (AJs) in human breast carcinoma cell line MDA-MB-435.
E-cadherin mediates calcium-dependent cell-cell adhesion between epithelial cells. The ectodomain of human E-cadherin contains four potential N-glycosylation sites at Asn residues 554, 566, 618, and 633. In this study, the role of N-glycosylation in E-cadherin-mediated cell-cell adhesion was investigated by site-directed mutagenesis. In MDA-MB-435 cells, all four potential N-glycosylation sites of human E-cadherin were N-glycosylated. Removal of N-glycan at Asn-633 dramatically affected E-cadherin stability. In contrast, mutant E-cadherin lacking the other three N-glycans showed similar protein stability in comparison with wild-type E-cadherin. Moreover, N-glycans at Asn-554 and Asn-566 were found to affect E-cadherin-mediated calcium-dependent cell-cell adhesion, and removal of either of the two N-glycans caused a significant decrease in calcium-dependent cell-cell adhesion accompanied with elevated cell migration. Analysis of the composition of adherens junctions (AJs) revealed that removal of N-glycans on E-cadherin resulted in elevated tyrosine phosphorylation level of beta-catenin and reduced beta- and alpha-catenins at AJs. These findings demonstrate that N-glycosylation may affect the adhesive function of E-cadherin through modifying the composition of AJs.
Zhao
Hongbo
H
Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032, PR China.
Liang
Yulong
Y
Xu
Zhibin
Z
Wang
Liying
L
Zhou
Feng
F
Li
Zengxia
Z
Jin
Jiawei
J
Yang
Yong
Y
Fang
Zhengyu
Z
Hu
Yali
Y
Zhang
Lineng
L
Su
Jianmin
J
Zha
Xiliang
X
D022005:Adherens Junctions / Q000737:chemistry*; D001943:Breast Neoplasms / Q000473:pathology*; D015820:Cadherins / Q000378:metabolism* / Q000502:physiology*; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D005260:Female; D006031:Glycosylation; D006801:Humans; D016297:Mutagenesis, Site-Directed; D010766:Phosphorylation; D011134:Polysaccharides; D051178:alpha Catenin / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism
D015820:Cadherins; D011134:Polysaccharides; D051178:alpha Catenin; D051176:beta Catenin