The transcriptomic response of green microalga Chlorella sorokiniana exposure to environmentally relevant concentration of cadmium(II) (Cd) and 4-n-nonylphenol (4-n-NP) was compared in the present study. Cd and 4-n-NP exposure showed a similar pattern of dys-regulated pathways. The photosystem was affected due to suppression of chlorophyll biosynthesis via down-regulation of Mg-protoporphyrin IX chelatase subunit ChlD (CHLD) and divinyl chlorophyllide a 8-vinyl-reductase (DVR) in Cd group and via down-regulation of DVR in 4-n-NP group. Furthermore, the reactive oxygen species (ROS) could be induced through down-regulation of solanesyl diphosphate synthase 1 (SPS1) and homogentisate phytyltransferase (HPT) in Cd group and via down-regulation of HPT in 4-n-NP group. Additionally, Cd and 4-n-NP would both cause the dys-regulation of carbohydrate metabolism and protein synthesis. On the other hand, there are some different responses or detoxification mechanism of C. sorokiniana to 4-n-NP stress compared to Cd exposure. The increased ROS would cause the DNA damage and protein destruction in Cd exposure group. Simultaneously, the RNA transcription was dys-regulated and a series of changes in gene expressions were observed. This included lipid metabolism, protein modification, and DNA repair, which involved in response of C. sorokiniana to Cd stress or detoxification of Cd. For 4-n-NP exposure, no effect on lipid metabolism and DNA repair was observed. The nucleotide metabolism including pyrimidine metabolism and purine metabolism was significantly up-regulated in the 4-n-NP exposure group, but not in the Cd exposure group. In addition, 4-n-NP would induce the ubiquitin-mediated proteolysis and proteasomal degradation to diminish the misfolded protein caused by ROS and down-regulation of heat shocking protein 40. In sum, the Cd and 4-n-NP could cause the same toxicological effects via the common pathways and possess similar detoxification mechanism. They also showed different responses in nucleotide metabolism, lipid metabolism, and DNA repair.

在本研究中比较了绿色微藻小球藻小球藻暴露于环境相关浓度的镉（II）（Cd）和4-正壬基苯酚（4- n -NP）的转录反应。Cd和4- n -NP暴露显示出类似的失调调节途径。由于Cd组中Mg-原卟啉IX螯合酶亚基ChlD（CHLD）和二乙烯基叶绿素a 8-乙烯基还原酶（DVR）的下调，以及Cd组中DVR的下调，从而抑制了叶绿素的生物合成，从而影响了光系统。ñ-NP组。此外，可通过下调Cd组茄二酰基二磷酸合成酶1（SPS1）和尿黑酸植酸转移酶（HPT）以及通过下调4- n -NP组HPT来诱导活性氧（ROS）。另外，Cd和4- n- NP都将引起碳水化合物代谢和蛋白质合成的失调。另一方面，C。sorokiniana对4- n的反应或解毒机制有所不同。-NP胁迫与Cd暴露相比。ROS增加会导致镉暴露组DNA损伤和蛋白质破坏。同时，RNA转录失调，并观察到一系列基因表达的变化。这包括脂质代谢，蛋白质修饰和DNA修复，这些过程涉及C. sorokiniana对Cd胁迫或Cd解毒的反应。对于4- n- NP暴露，未观察到对脂质代谢和DNA修复的影响。在4- n- NP暴露组中，包括嘧啶代谢和嘌呤代谢在内的核苷酸代谢显着上调，而在Cd暴露组中则没有。另外，4- n-NP会诱导泛素介导的蛋白水解和蛋白酶体降解，从而减少由ROS和热休克蛋白40的下调引起的错折叠蛋白。总而言之，Cd和4- n -NP可能通过共同的作用引起相同的毒理作用。并具有类似的排毒机理。他们还在核苷酸代谢，脂质代谢和DNA修复方面显示出不同的反应。