Functionally distinct laminin receptors mediate cell adhesion and spreading: the requirement for surface galactosyltransferase in cell spreading.
Functionally distinct laminin receptors mediate cell adhesion and spreading: the requirement for surface galactosyltransferase in cell spreading.
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DOI：
10.1083/jcb.107.5.1863
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发表时间：
1988-11
期刊：
影响因子：
--
通讯作者：
Shur BD
中科院分区：
文献类型：
--
作者：
Runyan RB;Versalovic J;Shur BD
细胞附着和随后的细胞在层粘连蛋白上扩散的分子机制被证明是彼此不同的。细胞扩散取决于细胞表面半乳糖基转移酶 (GalTase) 与层粘连蛋白寡糖的结合，而细胞与层粘连蛋白的初始附着与 GalTase 活性无关。抗 GalTase IgG 以及 GalTase 修饰蛋白 α-乳清蛋白均能阻断 GalTase 活性并抑制 B16-F10 黑色素瘤细胞在层粘连蛋白上扩散，但不能抑制初始附着。另一方面，添加 UDP 半乳糖会增加 GalTase 的催化周转，从而略微增加细胞铺展。这些试剂对纤连蛋白上的细胞铺展没有任何影响。当层粘连蛋白内的 GalTase 底物被亲和纯化的 GalTase 阻断或通过先前的半乳糖基化消除时，细胞附着看起来正常，但随后的细胞扩散完全受到抑制。 GalTase 的层粘连蛋白底物被鉴定为主要位于 A 链上的 N 连接寡糖，其次是 B 链上的 N 连接寡糖。即使细胞附着正常，细胞也无法在用 N-聚糖酶预处理的层粘连蛋白表面上铺展，这表明 N-连接寡糖对于细胞铺展是必需的。细胞表面 GalTase 与其他报道的层粘连蛋白结合蛋白（最著名的是 68-kD 受体）不同，因为它们从层粘连蛋白亲和柱中洗脱有差异。这些数据表明，表面 GalTase 不参与初始细胞粘附到层粘连蛋白的过程，但通过与其适当的 N-连接寡糖底物结合来介导随后的细胞扩散。这些结果还强调，层粘连蛋白的一些生物学特性可归因于其寡糖残基。
The molecular mechanisms underlying cell attachment and subsequent cell spreading on laminin are shown to be distinct form one another. Cell spreading is dependent upon the binding of cell surface galactosyltransferase (GalTase) to laminin oligosaccharides, while initial cell attachment to laminin occurs independent of GalTase activity. Anti-GalTase IgG, as well as the GalTase modifier protein, alpha-lactalbumin, both block GalTase activity and inhibited B16-F10 melanoma cell spreading on laminin, but not initial attachment. On the other hand, the addition of UDP galactose, which increases the catalytic turnover of GalTase, slightly increased cell spreading. None of these reagents had any effect on cell spreading on fibronectin. When GalTase substrates within laminin were either blocked by affinity- purified GalTase or eliminated by prior galactosylation, cell attachment appeared normal, but subsequent cell spreading was totally inhibited. The laminin substrate for GalTase was identified as N-linked oligosaccharides primarily on the A chain, and to a lesser extent on B chains. That N-linked oligosaccharides are necessary for cell spreading was shown by the inability of cells to spread on laminin surfaces pretreated with N-glycanase, even though cell attachment was normal. Cell surface GalTase was distinguished from other reported laminin binding proteins, most notably the 68-kD receptor, since they were differentially eluted from laminin affinity columns. These data show that surface GalTase does not participate during initial cell adhesion to laminin, but mediates subsequent cell spreading by binding to its appropriate N-linked oligosaccharide substrate. These results also emphasize that some of laminin's biological properties can be attributed to its oligosaccharide residues.
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DOI：
10.1083/jcb.103.6.2457
发表时间：
1986-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
通讯作者：
--
DOI：
10.1083/jcb.101.6.2134
发表时间：
1985-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Horwitz A;Duggan K;Greggs R;Decker C;Buck C
通讯作者：
Buck C
DOI：
10.1083/jcb.96.5.1475
发表时间：
1983-05
期刊：
The Journal of cell biology
影响因子：
--
作者：
Malinoff HL;Wicha MS
通讯作者：
Wicha MS
DOI：
10.1111/j.1432-1033.1974.tb03599.x
发表时间：
1974-01-01
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
BONNER, WM;LASKEY, RA
通讯作者：
LASKEY, RA
影响因子：
64.5
作者：
BAYNA, EM;SHAPER, JH;SHUR, BD
通讯作者：
SHUR, BD