Synthesis of collagenous proteins by pulmonary type II epithelial cells.
Synthesis of collagenous proteins by pulmonary type II epithelial cells.
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肺 II 型上皮细胞合成胶原蛋白。
DOI：
10.1164/arrd.1987.135.5.1118
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Longmore,W
中科院分区：
文献类型：
--
作者：
Crouch,EC;Moxley,MA;Longmore,W
我们研究了大鼠肺上皮细胞（II型肺细胞）的原代培养物的胶原蛋白的生产。三个主要的细菌胶原酶敏感链的合成和分泌到培养基中的12和36小时之间的文化。在十二烷基硫酸钠-聚丙烯酰胺平板凝胶电泳（SDS-PAGE）上，两条链与从成年大鼠肺中分离的放射性标记的IV型前胶原（PC）链（还原后Mr= 185，000和170，000）共迁移，并与IV型胶原的单特异性抗体共沉淀。色谱纯化链的溴化氰（CNBr）肽图谱与大鼠肺IV型PC图谱相同，并证实这些链为proα1（IV）和proα2（IV）。IV型PC是细胞层中主要的高分子量胶原蛋白，并且新合成的IV型PC的一部分与新合成的纤连蛋白一起选择性地沉积在基质上。II型细胞还分泌低分子量、非二硫键、胶原酶敏感蛋白（Mr= 19，000，胶原标准品;Mr= 26，000，球状标准品）。蛋白质共洗脱与IV型PC从DEAE-纤维素，但从CM-纤维素上的天然IV型解析。该蛋白质没有沉淀与IV型胶原蛋白或大鼠表面活性剂脱辅基蛋白的多克隆抗体。这些研究进一步证实了肺上皮细胞体外合成胶原大分子的异质性。我们认为，肺细胞衍生的纤连蛋白和IV型前胶原之间的相互作用有助于上皮基底膜的形成和这些细胞在正常或损伤的肺的附着。
We have investigated the production of collagenous proteins by primary cultures of rat lung epithelial cells (type II pneumocytes). Three major bacterial collagenase-sensitive chains were synthesized and secreted into the medium between 12 and 36 h of culture. Two of the chains comigrated on sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis (SDS-PAGE) with radiolabeled type IV procollagen (PC) chains isolated from adult rat lung (Mr= 185,000 and 170,000 after reduction) and were coprecipitated with monospecific antibodies to type IV collagen. Cyanogen bromide (CNBr) peptide maps of the chromatographically purified chains were identical to maps of rat lung type IV PC, and confirmed the identity of these chains as proα1(IV) and proα2(IV). Type IV PC was the major high molecular weight collagen in the cell layer, and a fraction of the newly synthesized type IV PC was selectively deposited on the substratum together with newly synthesized fibronectin. Type II cells also secreted a low molecular weight, non-disulfide-bonded, collagenase-sensitive protein (Mr= 19,000, collagen standards;Mr= 26,000, globular standards). The protein coeluted with type IV PC from DEAE-cellulose but was resolved from native type IV on CM-cellulose. The protein was not precipitated with polyclonal antibodies to type IV collagen or rat surfactant apoprotein. These studies further demonstrate the heterogeneity of collagenous macro-molecules synthesized by lung epithelial cellsin vitro. We suggest that interactions between pneumocyte-derived fibronectin and type IV procollagen contribute to the formation of the epithelial basement membrane and to the attachment of these cells in normal or injured lung.