Defining fibronectin's cell adhesion synergy site by site-directed mutagenesis.
Defining fibronectin's cell adhesion synergy site by site-directed mutagenesis.
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DOI：
10.1083/jcb.149.2.521
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发表时间：
2000-04-17
期刊：
影响因子：
--
通讯作者：
Erickson HP
中科院分区：
文献类型：
--
作者：
Redick SD;Settles DL;Briscoe G;Erickson HP
纤连蛋白III结构域9（FN 9）内的协同位点显著增强了纤连蛋白的RGD介导的与α5β1整联蛋白的结合。在细胞结合结构域的晶体结构的指导下，我们选择了FN 9中与RGD方向相同的氨基酸，推测为整合素，并将其突变为丙氨酸。肽PHSRN中的R1379和附近的R1374先前已经显示对于α5β1介导的粘附是重要的（Aota，S.，M. Nomizu和K.M.山田1994. 269：24756-24761）。我们更广泛的突变体组表明，R1379是协同效应中的关键残基，但其他残基也有很大贡献。R1374 A自身略微降低粘附性，但双突变体R1374 A-R1379 A的粘附性显著低于单独的R1379 A。R1369 A、R1371 A、T1385 A和N1386 A的单一突变对细胞粘附的影响可以忽略不计，但是将这些取代与R1379 A或彼此组合，得到细胞粘附的更显著降低。三突变体R1374 A/P1376 A/R1379 A没有可检测的粘附活性。我们得出结论，除了PHRSN肽的R之外，FN 9的同一面上的其他残基是完全协同效应所需的。整合素结合协同位点是比小的线性肽序列更广泛的表面。
Fibronectin's RGD-mediated binding to the α5β1 integrin is dramatically enhanced by a synergy site within fibronectin III domain 9 (FN9). Guided by the crystal structure of the cell-binding domain, we selected amino acids in FN9 that project in the same direction as the RGD, presumably toward the integrin, and mutated them to alanine. R1379 in the peptide PHSRN, and the nearby R1374 have been shown previously to be important for α5β1-mediated adhesion (Aota, S., M. Nomizu, and K.M. Yamada. 1994. J. Biol. Chem. 269:24756–24761). Our more extensive set of mutants showed that R1379 is the key residue in the synergistic effect, but other residues contribute substantially. R1374A decreased adhesion slightly by itself, but the double mutant R1374A-R1379A was significantly less adhesive than R1379A alone. Single mutations of R1369A, R1371A, T1385A, and N1386A had negligible effects on cell adhesion, but combining these substitutions either with R1379A or each other gave a more dramatic reduction of cell adhesion. The triple mutant R1374A/P1376A/R1379A had no detectable adhesion activity. We conclude that, in addition to the R of the PHRSN peptide, other residues on the same face of FN9 are required for the full synergistic effect. The integrin-binding synergy site is a much more extensive surface than the small linear peptide sequence.
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影响因子：
64.5
作者：
OBARA, M;KANG, MS;YAMADA, KM
通讯作者：
YAMADA, KM
影响因子：
7.8
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Ramos, JW;DeSimone, DW
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64.8
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4.8
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García, AJ;Takagi, J;Boettiger, D
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Boettiger, D
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4.8
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Banères, JL;Roquet, F;Parello, J
通讯作者：
Parello, J