Study On The Immune Regulation Mechanism Of MicroRNA-21 On IL1R1 In Miichthys Miiuy

Innate Immune is the first line of defense and eliminate invading pathogens for organisms.It mainly serves to defend,monitor and maintain the stability of the internal environment.The immune system has bidirectional regulation,it can not only clear the invasion of pathogens,but also prevent excessive immune response when the immune system is disordered thereby damage its own cells.IL1R1(Interleukin-1 receptor 1)is an important immune gene on the cell surface.It is a high-affinity receptor for interleukin-1(IL-1)and plays an important role in the inflammatory response and immune signal transduction of organisms.Based on the important role of this receptor in the immune system,it is particularly important to study the regulation of the immune response of the organism by regulating the expression of IL1R1.In recent years,microRNA was discovered as a short-chain noncoding RNA(22-24 nt),which can be paired with a specific sequence of the target gene's 3'UTR region through a sequence of about 4-8 bases,thereby inhibit the translation of gene mRNA,and it can regulate immune system.As an important economic aquaculture species,miiuy croaker is very popular credit to its important edible and medicinal value.In this article,we have studied the negative regulatory effect of miR-21 on the IL1R1.Experimental method: we mainly used plasmid construction,dual luciferase reporter gene experiment,Western Blot and other experimental methods to study the relationship between miR-21 and IL1R1.The results was shown that miR-21 can negatively regulate IL1R1.The specific methods are as follows: First,we constructed the miiuy croaker IL1R1-3'UTR dual luciferase reporter gene and pre-miR-21 plasmids.The dual luciferase reporter gene experiment confirmed that miR-21 negative regulates IL1R1-3'UTR,and we further confirmed that the endogenous pre-miR-21 also negative regulatory IL1R1-3'UTR.Then,through fluorescence quantitative PCR(qRT-PCR)experiments,we have proved that both miR-21 and pre-miR-21 can significantly inhibit the expression of IL1R1 mRNA.In addition,we have confirmed that miR-21 and pre-miR-21 can also negative regulates IL1R1 activation NF-?B and other signaling pathway reporter genes.Finally,Western blot experiments confirmed that miR-21 inhibited IL1R1 protein expression.To sum up,we conclude that miR-21 regulates the inflammation and immune response of miiuy croaker by negatively regulating IL1R1.