Fisher J H, Shannon J M, Hofmann T, Mason R J
Department of Medicine, University of Colorado Health Sciences Center, Denver 80262.
Biochim Biophys Acta. 1989 May 1;995(3):225-30. doi: 10.1016/0167-4838(89)90040-x.
Pulmonary surfactant lowers surface tension in the lung. Its deficiency leads to the severe physiologic abnormalities seen in the respiratory distress syndrome. The hydrophobic surfactant proteins, SP-B and SP-C, appear to be especially important in the surface-spreading characteristics of pulmonary surfactant. We report the nucleotide sequence of cDNA clones for rat SP-C and compare the deduced amino acid sequence for SP-C from several species. A highly conserved domain exists within the confines of mature human SP-C. An Eisenberg plot of this region predicts a membrane-associated helix. We also demonstrate by Northern analysis the tissue-specific expression of SP-C. A comparison of signal strength between total lung RNA and RNA derived from isolated type II cells supports the idea that most SP-C messenger RNA in total lung can be accounted for by that present in alveolar type II cells.
肺表面活性物质可降低肺内表面张力。其缺乏会导致呼吸窘迫综合征中出现的严重生理异常。疏水性表面活性物质蛋白SP - B和SP - C似乎在肺表面活性物质的表面铺展特性中尤为重要。我们报告了大鼠SP - C的cDNA克隆的核苷酸序列，并比较了几种物种SP - C的推导氨基酸序列。成熟的人SP - C范围内存在一个高度保守的结构域。该区域的艾森伯格图预测有一个与膜相关的螺旋。我们还通过Northern分析证明了SP - C的组织特异性表达。总肺RNA与来自分离的II型细胞的RNA之间信号强度的比较支持这样的观点，即总肺中大多数SP - C信使RNA可由肺泡II型细胞中的信使RNA来解释。
