BINDING OF SOLUBLE TYPE-1 COLLAGEN MOLECULES TO THE FIBROBLAST PLASMA-MEMBRANE
BINDING OF SOLUBLE TYPE-1 COLLAGEN MOLECULES TO THE FIBROBLAST PLASMA-MEMBRANE
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DOI：
10.1016/0092-8674(79)90004-7
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发表时间：
1979-01-01
期刊：
影响因子：
64.5
通讯作者：
GOLDBERG, B
中科院分区：
文献类型：
--
作者：
GOLDBERG, B
可溶性~(125)I标记的大鼠皮肤I型胶原与培养的成纤维细胞结合，但不与培养的上皮细胞结合。配体与成纤维细胞的结合是可逆的、可饱和的，并且对于α1和α2链的螺旋部分中包含的序列具有高度特异性。配体的结合量依赖于细胞数量和配体浓度。结合力降低，但在4度时可测到。C.在26度时，稳态结合较大。而不是37度。C，这是由于配体-受体络合物在37℃时解离得更快。C.络合物在37度时的半衰期为46min。C，在26度时约2.5小时。C.结合数据的Scatchard图表明只有一类高亲和力结合位点(Kd=1.2×.10-11M)，每个成纤维细胞饱和时结合约500,000个分子。细菌胶原酶、软骨素酶ABC或睾丸透明质酸酶对成纤维细胞的结合无影响；磷脂酶C可增加细胞的配体结合量。去除表面纤维连接蛋白的胰酶浓度处理成纤维细胞后，配体结合减少，但不会被取消。纤维连接蛋白抗血清处理的成纤维细胞单层与放射性标记的配体正常结合。与胶原相反，过量的纤维连接蛋白不会加速结合配体从成纤维细胞中解离。讨论了表面结合胶原蛋白的可能功能。
Soluble 125I-labeled type I rat skin collagen bound to cultured fibroblasts but not to cultured epithelia. The binding of the ligand to fibroblasts was reversible, saturable and highly specific for sequences contained within the helical portions of the .alpha.1 and .alpha.2 chains. The amount of ligand bound was dependent upon cell number and ligand concentration. Binding was decreased but measurable at 4.degree. C. The steady state binding was greater at 26.degree. than at 37.degree. C due to a more rapid dissociation of the ligand-acceptor complex at 37.degree. C. The half-life of the complex was 46 min at 37.degree. C and approximately 2.5 h at 26.degree. C. Scatchard plots of binding data indicated a single class of high affinity binding sites (KD = 1.2 .times. 10-11 M) with each fibroblast binding approximately 500,000 molecules at saturation. Pretreatment of fibroblasts with bacterial collagenase, chondroitinase ABC or testicular hyaluronidase did not affect the binding reaction; pretreatment of the cells with phospholipase C increased the amount of ligand bound. Ligand binding was decreased but not abolished after fibroblasts were treated with trypsin concentrations which remove surface fibronectin. Fibroblast monolayers treated with antiserum against fibronectin bound the radiolabeled ligand normally. In contrast to collagen, addition of excess fibronectin did not accelerate the dissociation of bound ligand from fibroblasts. Possible functions for surface-bound collagen were discussed.