title: Identification of nucleolin as a lipid-raft-dependent β1-integrin-interacting protein in A375 cell migration.
abstract: Lipid rafts are related to cell surface receptor function. Integrin is a major surface receptor protein in cell adhesion and migration on the extracellular matrix (ECM). Here, we showed that lipid rafts played a critical role in human melanoma A375 cell spreading and migration on fibronectin; an important component of the ECM that interacts with β1 integrin. We found that the disruption of lipid rafts did not markedly inhibit the expression and activation of β1 integrin. By coimmunoprecipitation and mass spectrometry, we investigated the influence of lipid rafts on the β1 integrin complex and identified nucleolin as a potential lipid-raft-dependent β1-integrin-interacting protein. Upon confirmation of the interaction between β1 integrin and nucleolin, further studies revealed that nucleolin colocalized with β1 integrin in lipid rafts and raft disruption interrupted their association. In addition, knockdown of nucleolin markedly attenuated A375 cell spreading and migration on fibronectin. Taken together, we demonstrated that nucleolin is a critical lipid-raft-dependent β1-integrin-interacting protein in A375 cell spreading and migration on fibronectin.
authors.affiliation: Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, Changchun, Jilin, 130024, China.
authors.forename: Jiajia
authors.initials: J
authors.lastname: Bi
authors.forename: Ruifei
authors.initials: R
authors.lastname: Wang
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Han
authors.forename: Khamal Kwesi
authors.initials: KK
authors.lastname: Ampah
authors.forename: Wenguang
authors.initials: W
authors.lastname: Liu
authors.forename: Xianlu
authors.initials: X
authors.lastname: Zeng
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D005353:Fibronectins / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D019012:Integrin beta1 / Q000235:genetics* / Q000378:metabolism*; D013058:Mass Spectrometry; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D021962:Membrane Microdomains / Q000378:metabolism*; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D047392:beta-Cyclodextrins / Q000494:pharmacology; D000097796:Nucleolin
chemical_list: D005353:Fibronectins; D019012:Integrin beta1; D010750:Phosphoproteins; D016601:RNA-Binding Proteins; D047392:beta-Cyclodextrins; D000097796:Nucleolin; C108732:methyl-beta-cyclodextrin