Effects Of Heavy Metal Stress On The Biological Characteristics And Differential Expression Of CuZnSOD/MnSOD Gene In Eurytemora Pacifica

With the increasing pollution of marine heavy metals,the marine ecological environment has been severely damaged and has become an important environmental issue that people are concerned about.In view of the sensitivity of copepods to marine pollutants,it plays a significant role in monitoring and prevention and control of global marine ecological environment.At the same time,it is an open-ended bait for fish and shrimp larvae and has important research valueit will make a significant sense in fishery production and aquaculture research..Superoxide dismutase?SOD?is a as metalloenzyme,is widely found in microorganisms,animal and plant cells,and it is an important antioxidant enzyme in the active oxygen scavenging system in the body.It also plays an important regulatory role in metal toxicity stress immunity.Therefore,in this paper,we take the China's East China Sea planktonic copepods widely distributed in China's East China Sea as the research object,and use the common heavy metals chromium and nickel as target pollutants in the ocean to carry out acute toxicity experiments.The 48h-LC50 was determined.RACE technology was used to clone the CuZnSOD/MnSO gene from the Pacific Ocean,and sequence analysis was performed.On this basis,we investigated the expression changes of CuZnSOD/MnSO gene in the Pacific wide-area superoxide dismutase under the single action and combined action of different concentrations of chromium and nickel,and explored the acute toxicity of the heavy metal stress to Pacific wide-leaved pelican.And the joint toxic effects provide reference materials for the future development of bio-monitoring and ecological risk assessment of pollutants under the single action and joint action of heavy metals in the marine environment and the development of fishery culture.This article is divided intohas 4 chapters:First Chapter is an I Introduction.It mainly discusses the progress of marine heavy metal pollution and biological monitoring and evaluation,the overall overview of copepods,and the application of superoxide dismutase in toxicology analysis.It Presents the status and characteristics of heavy metal pollution in the oceans,introduces the research progress on biological and biological markers of marine heavy metal pollution indicators,and briefs the ecological status of copepods in nature,the value and significance of copepods in ecotoxicology and molecular toxicology.An overview of the Pacific Ocean's really wide waters.It analyses The role of copepods in the monitoring and evaluation of heavy metal pollution in the ocean was analyzed,and discusses the application prospect and research value of the cockropods as an indicator organism were discussed.The second chapter is the acute toxicity of heavy metals on the Pacific wide blister.In this chapter,we make a study about the acute toxic effects of chromium and nickel and their joint exposures on Pacific wide blister were studied.The single-acting semi-lethal concentrations of chromium and nickel under single action and combined effects of them on the 48-hour acute acute lethality of Pacific sea bream were measured.(48h-LC₅₀)were986.68?g/L,4635.91?g/L,combined chromium 170.12?g/L,and nickel combined817.08?g/L,respectively.The results showed that the physiotoxicity of Cryptospora in the Pacific Ocean under the single action of heavy metals was Cr³⁺>Ni²⁺.Under the combined action of stress,S=0.35 and AI=1.86.It shows that the combined toxicity of chromium and nickel is synergistic.The third Chapter shows the Cloning and Biological Characteristics Analysis of CuZnSOD/MnSOD cDNA Encoding Superoxide Dismutase from the Pacific Ocean.In this study,all the total RNA was extracted from the genus Polygonum of the Pacific Ocean.The full-length cDNA sequence of CuZnSOD/MnSOD was obtained by RACE.The biological characteristics analysis showed that the CuZnSOD?GenBank accession number:MF289343?was 837 bp in length,the open reading frame?ORF?consisted of 465 bp nucleotides and encoded a total of 152 amino acids;the 5?non-coding region was 297 bp long,3?non-The coding region is 84 bp long with a molecular weight of approximately15.050 kDa and a theoretical isoelectric point of 5.73.MnSOD?GenBank accession number:MF289344?has a total length of 865bp,an ORF of 600bp,encoding 223 amino acids,a 5'non-coding region of 134bp,a 3'non-coding region of 131bp,a molecular weight of approximately 71.4709 kDa,and a theoretical isoelectric point of 5.11..The amino acid sequence homology analysis showed that the CuZnSOD/MnSOD genes in the Pacific Ocean had higher similarity with crustaceans and copepods.The cluster analysis showed that the CuZnSOD/MnSOD genes were clustered with the pupa.Crabs and crustaceans in crustaceans are relatively distant and highly conserved.In the fourth chapter,it presents tThe influence of heavy metals on the expression of superoxide dismutase CuZnSOD/MnSOD in the Pacific wide-leaved oysters in the fourth chapter.The changes in the expression of CuZnSOD and MnSOD genes in the Pacific wide blister were studied under the single and combined effects of heavy metal chromium and nickel at different concentrations.Studies have shown that MnSOD prevents metal toxic stress and protects cells during heavy metal oxidative damage.It is stronger than CuZn SOD gene to protect from oxidative damage to lay a foundation for further understanding of the changes in the expression of related genes in leech in physiological mechanisms of toxicity.