The Antioxidant Function Of HSP27 And Ferritin From Macrobrachium Nipponense

Due to high density culture and serious environment pollution,intracellular reactive oxygen species?ROS?increased or accumulated in the aquatic animals,resulting severe cell damages and even multiple diseases.Therefore it is of great significance to study the anti-oxidation mechanism of aquatic animals,especially aquaculture animals.Though some scientists have revealed that several mall heat shock proteins?sHSP?and Ferritin probably took part in the antioxidant process,the reseaches on Macrobrachium nipponense rarely involved sHSP and Ferritin.Based on a transcriptional database of M.nipponense in our laboratory,we discovered a sequence of HSP27 and four sequences of Ferritin,which was named MnHSP27?MnFer2?MnFer3?MnFer4?MnFer5.Moreover,it was explored whether they participated in the process of antioxidation in M.nipponense.The main results were as follows:1.MnHSP27 and MnFerritins were successfully inducible expressed by prokaryotic expression system,and recombinant protein of MnFer2?rMnFer2?was active to bind with iron ions in vitro.2.We analyzed the expression patterns of MnHSP27 and MnFerritin genes in different tissues and after Aeromonas veronii infection.The qPCR results showed that MnHSP27 was relatively highest expressed in the part of muscle,and that the genes of Mn Fer2?MnFer3?MnFer4 were relatively higher in the part of hepatopancreas,gill and intestine,gill and muscle respectively.With the stimulation of Aeromonas veronii,there was no significantly change in the expression of MnHSP27 mRNA,while the expression of MnHSP27 protein showed down-regulated trend with Western blot.It was nearly consistent that the relatively expression of MnFer2?MnFer3 and MnFer4 mRNA was all down-regulated first and then backed to the nomal level or even up-regulated.3.In order to determine the antioxidant function of MnHSP27 and MnFerritin,we discovered that rMnHSP27?rMnFer2 and rMnFer3 can protect Escherichia coli against from H₂O₂.Further after doxorubicin stimulation in M.nipponense,both the ROS level and the content of MDA were raised,at the same time,the expression dramatically increased between MnHSP27 and MnFer2,while the expression of MnFer3 and MnFer4 was reduced with qPCR.These results pointed out that both MnHSP27 and MnFer2 may play an antioxidant role during oxidative stress by doxorubicin in M.nipponense,which would provide reference for exploring the anti-oxidation mechanism of crustaceans in deep.