David Helen E, Dawe Adam S, de Pomerai David I, Jones Don, Candido E Peter M, Daniells Clare
Safety and Environmental Assurance Centre, Unilever Research Port Sunlight, Quarry Road East, Bebington, Wirral CH63 3JW, United Kingdom.
Environ Toxicol Chem. 2003 Jan;22(1):111-8.
A novel integrated transgenic Caenorhabditis elegans strain (PC161) incorporates a double reporter construct with green fluorescent protein (GFP) and lacZ genes fused in-frame into the second exon of the hsp16-1 gene. This construct also includes the Simian Virus 40 (SV40) nuclear localization signal such that the fusion protein accumulates in the nuclei of expressing cells. The PC161 strain was used to monitor the effects of several known stressors, including heat, cadmium, and microwave radiation. The time course of induction was similar for both reporters but was strongly influenced by pretreatment conditions. The PC161 worms kept at 15 degrees C beforehand showed a steady increase in reporter expression (up to at least 16 h) when heated to 30 degrees C. However, if washed on ice prior to heat stress at 30 degrees C, PC161 worms showed a much steeper rise in reporter expression, reaching a maximum after 2.5 h and then plateauing. Heat shock induced strong expression of both reporter genes in all tissues apart from the germ line and early embryos. A highly significant linear dose-response relationship was observed for both transgenes with increasing cadmium concentrations (5-100 microg/ml). Prolonged exposure to microwave radiation (750 MHz and 0.5 W for 16 h) also induced expression of both transgenes at 25 and (to some extent) 27 degrees C, but only beta-galactosidase activity was detectable at 23 degrees C, and neither reporter was detectably expressed at 21 degrees C. Throughout all exposures, the lacZ reporter product was more readily detectable than coexpressed GFP. However, the GFP reporter affords opportunities to monitor the stress response in living worms.
一种新型的整合转基因秀丽隐杆线虫品系（PC161）包含一个双报告基因构建体，其中绿色荧光蛋白（GFP）和lacZ基因读框内融合到hsp16-1基因的第二个外显子中。该构建体还包括猴病毒40（SV40）核定位信号，使得融合蛋白在表达细胞的细胞核中积累。PC161品系用于监测几种已知应激源的影响，包括热、镉和微波辐射。两个报告基因的诱导时间进程相似，但受到预处理条件的强烈影响。预先保持在15摄氏度的PC161线虫在加热到30摄氏度时，报告基因表达呈稳定增加（至少持续16小时）。然而，如果在30摄氏度热应激前在冰上洗涤，PC161线虫的报告基因表达上升幅度大得多，在2.5小时后达到最大值，然后趋于平稳。热休克在除生殖系和早期胚胎外的所有组织中诱导两个报告基因的强烈表达。随着镉浓度增加（5-100微克/毫升），两个转基因均观察到高度显著的线性剂量反应关系。长时间暴露于微波辐射（750兆赫和0.5瓦，持续16小时）也在25摄氏度以及（在一定程度上）27摄氏度诱导两个转基因的表达，但在23摄氏度仅可检测到β-半乳糖苷酶活性，在21摄氏度两个报告基因均未检测到可检测的表达。在所有暴露过程中，lacZ报告基因产物比共表达的GFP更容易检测到。然而，GFP报告基因提供了监测活线虫应激反应的机会。
