Preliminary Study On Expression Characteristics And Function Of Ferritin Gene In Ctenopharyngodon Idella

Grass carp(Ctenopharyngodon idella)is one of the most important freshwater aquaculture fish in China,and plays an extremely important role in the aquaculture of the four major fishes.However,the high mortality rate caused by the perennial reovirus infection has caused great economic losses to the aquaculture industry,which seriously restricts the healthy,efficient and sustainable development of the aquaculture industry.Under the background of grass carp aquaculture severe,this group is immune to grass carp for years has carried on the various research,found in the studies on grass carp maternal immune,maternal immune treatment can enhance the grass carp progeny GCRV resistance,and the maternal immunization grass carp and common grass carp eggs protein group compare analysis found that Ferritin protein after maternal immune treatment were significantly raised.Based on these findings,this study obtained the Ferritin gene of grass carp,explored its expression characteristics in the immune response of grass carp,and used the progeny of maternal immune treatment and progeny of common grass carp as raw materials to analyze its intergenerational transfer and epigenetic inheritance in Ferritin.The aim is to understand the function of Ferritin in grass carp and the mechanism of Ferritin gene expression in maternal immune treatment,so as to provide reference for genetic selection and breeding of stress-resistant grass carp.The main research contents of this paper are as follows:1.Full length cloning and bioinformatics analysis of Ferritin cDNA from grass carp.The full-length cDNA of grass carp Ferritin was amplified by RACE technology.The sequence entry number was MK934175.1,and its ORF coding region encoded 176 amino acids in total.Bioinformatics analysis showed that there was only one Ferritin domain,no transmembrane helix and no signal peptide,and the results of multiple sequence alignment and phylogenetic tree showed that the Ferritin gene of grass carp was highly conserved in genetics.2.Tissue expression characteristics of Ferritin in grass carp.The Ferritin expression in normal tissues,GCRV challenged tissues and early embryos of grass carp were detected by qRT-PCR.The results showed that Ferritin gene was expressed in all the 10 tissues,and the expression was higher in spleen and kidney.After GCRV infection,the expression level of Ferritin in both spleen and kidney of grass carp showed a trend of first increasing,then decreasing and then increasing,indicating that Ferritin was involved in the immune response of grass carp.3.Regulation mechanism analysis of Ferritin gene expression level in grass carp.The methylation level of Ferritin gene in the progeny of immunized grass carp and common grass carp were detected by heavy sulfite sequencing method and MALDI-TOF mass spectrometry,and the correlation between methylation level and mRNA expression was analyzed.The results showed that the methylation level of Ferritin gene promoter was significantly lower in the progeny of parent carp treated with GCRV attenuated vaccine than in the progeny of common grass carp,and the Ferritin mRNA expression level was significantly higher than that of progeny of common grass carp.In the process of intergenerational transmission,the expression level of Ferritin was higher in eggs and fertilized eggs,and lower than that in the progeny control group of common grass carp from the two-cell to anthesis stage,which confirmed the intergenerational transmission of Ferritin in maternal immunity.