| In recent years,crayfish has become an important economic species in our country.However,due to the undeveloped disease prevention and control methods,the spread of diseases has led to widespread death of crayfish.Crayfish,as invertebrates,only relies on the innate immune system to resist external pathogens.Therefore,the in-depth study of the innate immune mechanism of crayfish is helpful to solve a series of problems in the breeding process,such as disease prevention.We screened a molecule containing a single reeler domain in Procambarus clarkii,and found that it was highly expressed in gills and its expression was significantly responded to bacterial stimulation.We named the gene PcReeler.This article chose PcReeler as the object to study its role and functional mechanism in the antibacterial immunity of Procambarus clarkii.As crayfish lived in water,the gills were directly in contact with the water as the place for gas exchange.We studied the location of PcReeler on the gills and found that it may be related to the antibacterial mechanism of the gills in crayfish.Inhibiting the expression of PcReeler by RNAi,whether in normal water environment or in water with high concentration of bacteria,led to a significant increase in the total abundance of bacteria and the number of cultivable bacteria in the gills of the crayfish,and a significant decrease in the survival rate.It showed that gene silencing of PcReeler reduced the diversity of microorganisms and changed the structure of bacterial distribution and influenced the stability of the original flora in the gills using 16S rDNA high-throughput sequencing.The recombinant protein of PcReeler was express to examine for its functional research.rPcReeler had the ability to bind polysaccharide molecules and bacteria.It inhibited the formation of bacterial biofilms.Reeler removed and killed part of bacteria in vitro.These results provided direct evidence for PcReeler to play an important role in the antibacterial immune mechanism of Procambarus clarkii.Therefore,this study focused on the functional characteristics of PcReeler.It had the deeper understanding of the antibacterial function and mechanism of Procambarus clarkii at the molecular level.And it had theoretical guiding significance for the development of new crayfish disease prevention and control strategies. |
