Screening And Identification Of CircRNA Affecting The Replication Of Newcastle Disease Virus

ND is an acute,febrile,septic and highly contact infectious disease of poultry caused by NDV.NDV belongs to the Paramyxoviridae,Avulavirus,avian paramyxovirus type I,which can cause lethal infections to many birds.Non-coding RNA was considered to be the“dark matter”in the genome.The common non-coding RNAs include lnc RNA,circ RNA,and micro RNA,circ RNA is a type of closed circular non-coding RNA which connected by covalent bonds,and plays many important roles in many diseases,but the research between circ RNA and virus infections was not deeply,and there are no reports on the research between NDV and circ RNA.In order to explore the role of circ RNA in NDV infection,based on the whole transcriptome sequencing data of CEF cells which infected NDV,some circ RNAs were obtained through bioinformatics analysis.Totally,22 circ RNAs were predicted to be differentially expressed,of which 21 were down-regulated and 1 was up-regulated.18circ RNAs with|log₂Foldchange|>1.5 to be tested and two circ RNAs:gga?circ?0000857and gga?circ?0004276 were used identified using RT-PCR by divergent primers.The two circ RNAs were significantly up-regulated after NDV infection,only gga?circ?0000857 was in line with the results of bioinformatics analysis.Knock-down and overexpression of gga?circ?0000857 can inhibit the replication of NDV.The expression of the parental genes was not changed after knockdown and overexpress gga?circ?0000857.This suggests gga?circ?0000857 could regulate NDV replication in trans.We find that gga?circ?0000857 is composed of the 14th,15th and 17th exons of NISCH with a total length of 341 nt,mainly located in the cytoplasm,widely distributed in various tissues of chicken,no potential coding function,and there are potential binding site with gga-mi R-143-3p.Further,we found that the up-regulation of gga?circ?0000857caused by NDV infection is time-dependent but not dose-dependent.In summary,we screened out 2 circ RNAs based ont the whole transcriptome sequencing data of CEF cells which infect NDV.We find that gga?circ?0000857 can inhibit the NDV replication.We analyzed its expression and molecular characteristics.These provide a certain theoretical basis and data source for the follow-up further research on the interaction mechanism between circ RNA and NDV.