Biology Department, Redfield 352 MS-32, Woods Hole Oceanographic Institution, 45 Water Street, Woods Hole, MA 02543, USA.
Aquat Toxicol. 2010 Jun 1;98(1):74-82. doi: 10.1016/j.aquatox.2010.01.008. Epub 2010 Feb 4.
Ultraviolet (UV) radiation damages cell molecules, and has been suggested to up-regulate mammalian cytochrome P4501 (CYP1) genes through an aryl hydrocarbon receptor (AHR) mediated mechanism. In this study, embryos and larvae of zebrafish (Danio rerio) were exposed to UV to determine the effects on expression of CYP1 and stress response genes in vivo in these fish. Zebrafish embryos were exposed for varying times to UV on two consecutive days, with exposure beginning at 24 and 48h post-fertilization (hpf). Embryos exposed for 2, 4 or 6h twice over 2 days to UVB (0.62 W/m(2); 8.9-26.7 kJ/m(2)) plus UVA (2.05 W/m(2); 29.5-144.6 kJ/m(2)) had moderately (2.4+/-0.8-fold) but significantly up-regulated levels of CYP1A. UVA alone had no effect on CYP1A expression. Proliferating cellular nuclear antigen (PCNA) and Cu-Zn superoxide dismutase (SOD1) transcript levels were induced (2.1+/-0.2 and 2.3+/-0.5-fold, respectively) in embryos exposed to two 6-h pulses of 0.62 W/m(2) UVB (26.8 kJ/m(2)). CYP1A was induced also in embryos exposed to higher intensity UVB (0.93 W/m(2)) for two 3-h or two 4-h pulses (20.1 or 26.8 kJ/m(2)). CYP1B1, SOD1 and PCNA expression was induced by the two 3-h pulses of the higher intensity UVB, but not after two 4-h pulses of the higher intensity UVB, possibly due to impaired condition of surviving embryos, reflected in a mortality of 34% at that UVB dose. A single 8-h long exposure of zebrafish larvae (8dpf) to UVB at 0.93 W/m(2) (26.8 kJ/m(2)) significantly induced CYP1A and CYP1B1 expression, but other CYP1 genes (CYP1C1, CYP1C2 and CYP1D1) showed no significant increase. The results show that UVB can induce expression of CYP1 genes as well stress response genes in developing zebrafish, and that UVB intensity and duration influence the responses.
紫外线（UV）辐射会破坏细胞分子，并已被提议通过芳烃受体（AHR）介导的机制上调哺乳动物细胞色素 P4501（CYP1）基因。在这项研究中，斑马鱼（Danio rerio）的胚胎和幼虫暴露于 UV 下，以确定这些鱼类体内对 CYP1 和应激反应基因表达的影响。斑马鱼胚胎在受精后 24 和 48 小时（hpf）连续两天暴露于 UV 下，暴露时间为 2、4 或 6 小时。暴露于 UVB（0.62 W/m2；8.9-26.7 kJ/m2）加 UVA（2.05 W/m2；29.5-144.6 kJ/m2）两次 2 天的胚胎有中度（2.4+/-0.8 倍）但显著上调 CYP1A 水平。UVA 单独对 CYP1A 表达没有影响。暴露于两次 0.62 W/m2UVB（26.8 kJ/m2）6 小时脉冲的胚胎中，增殖细胞核抗原（PCNA）和 Cu-Zn 超氧化物歧化酶（SOD1）转录水平分别升高（2.1+/-0.2 和 2.3+/-0.5 倍）。暴露于两次 3 小时或两次 4 小时 0.93 W/m2UVB（20.1 或 26.8 kJ/m2）脉冲的胚胎也诱导了 CYP1A。CYP1B1、SOD1 和 PCNA 的表达被两次 3 小时的高强度 UVB 脉冲诱导，但两次 4 小时的高强度 UVB 脉冲后没有诱导，可能是由于幸存胚胎的状况受损，在该 UVB 剂量下死亡率为 34%。将斑马鱼幼虫（8dpf）单次暴露于 0.93 W/m2（26.8 kJ/m2）的 UVB 8 小时，显著诱导了 CYP1A 和 CYP1B1 的表达，但其他 CYP1 基因（CYP1C1、CYP1C2 和 CYP1D1）没有显著增加。结果表明，UVB 可诱导发育中斑马鱼 CYP1 基因和应激反应基因的表达，并且 UVB 强度和持续时间会影响这些反应。
