Segade F, Claudio E, Wrobel K, Ramos S, Lazo P S
Department of Functional Biology, Oviedo University, Spain.
J Immunol. 1995 Mar 1;154(5):2384-92.
Macrophage activation by silica is the initial step in the development of silicosis. To identify genes that might be involved in silica-mediated activation, RAW 264.7 mouse macrophages were treated with silica for 48 h, and a subtracted cDNA library enriched for silica-induced genes (SIG) was constructed and differentially screened. Nine cDNA clones (designated SIG-12, -14, -20, -41, -61, -81, -91, -92, and -111) were partially sequenced and compared with sequences in GenBank/EMBL databases. SIG-12, -14, and -20 corresponded to the genes for ribosomal proteins L13a, L32, and L26, respectively. SIG-61 is the mouse homologue of p21 RhoC. SIG-91 is identical to the 67-kDa high-affinity laminin receptor. Four genes were not identified and are novel. All of the mRNAs corresponding to the nine cloned cDNAs were inducible by silica. Steady-state levels of mRNAs in RAW 264.7 cells treated with various macrophage activators and inducers of signal transduction pathways were determined. A complex pattern of induction and repression was found, indicating that upon phagocytosis of silica particles, many regulatory mechanisms of gene expression are simultaneously triggered.
二氧化硅激活巨噬细胞是矽肺发生发展的起始步骤。为了鉴定可能参与二氧化硅介导激活过程的基因，将RAW 264.7小鼠巨噬细胞用二氧化硅处理48小时，构建了一个富含二氧化硅诱导基因（SIG）的消减cDNA文库，并进行差异筛选。对9个cDNA克隆（命名为SIG-12、-14、-20、-41、-61、-81、-91、-92和-111）进行了部分测序，并与GenBank/EMBL数据库中的序列进行比较。SIG-12、-14和-20分别对应核糖体蛋白L13a、L32和L26的基因。SIG-61是p21 RhoC的小鼠同源物。SIG-91与67 kDa高亲和力层粘连蛋白受体相同。有4个基因未被鉴定，是新基因。与9个克隆cDNA相对应的所有mRNA均可被二氧化硅诱导。测定了用各种巨噬细胞激活剂和信号转导途径诱导剂处理的RAW 264.7细胞中mRNA的稳态水平。发现了一种复杂的诱导和抑制模式，表明在吞噬二氧化硅颗粒后，许多基因表达的调控机制会同时被触发。
