Expression Pattern And Polymorphism Analysis Of Long Non-coding RNA Lnc-ALVE1-AS1 Associated With Chicken Disease Resistance

Endogenous retroviruses(ERVs)are allegedly derived from retroviruses that have previously infected organisms in evolution and are part of the genome composition of organisms.For example,human endogenous retroviruses account for about genomic sequences.Of 5 to 8%,most do not express.The researchers once considered that endogenous retroviruses belong to junk DNA sequences or nonsense sequences,and some scholars believe that they may be infectious.With the deepening of research on endogenous retroviruses,some endogenous retroviruses have been confirmed to play an important role in early embryonic development and embryonic stem cells.This study selected endogenous retrovirus-avian leukosis virus subgroup E(ALVE)as the research object,based on the current identification of chicken endogenous leukemia virus can produce antisense long non-coding RNA(lncRNA),and found that this antisense lncRNA is associated with cellular innate immunity.At present,as people continue to deepen their research on lncRNAs,it has been demonstrated that lncRNAs participate in a variety of physiological functions and the molecular regulation process of complex phenotype formation.And when its own sequence changes may lead to lncRNA molecular function changes,resulting in changes in the phenotypic traits of the body.Therefore,the study of polymorphism of lncRNA has received extensive attention from scholars at home and abroad.In poultry breeding,previously identified polymorphic sites that are closely related to growth performance,carcass traits,and meat quality traits are mainly focused on coding genes,and there are few studies on non-coding genes.This study focused on the expression pattern,polymorphism analysis of long non-coding RNA lnc-ALVE1-AS1 in chicken embryos,and the correlation with chicken disease resistance phenotype,and initially clarified the long non-coding RNA lnc-ALVE1-AS1 and chicken resistance.The relevance of the disease phenotype.The study focuses on the following three aspects:1 Identification of upstream and downstream sequences of avian retrovirus ALVE1 in chicken genomeThe chicken genome is known to contain the avian retrovirus ALVE1 sequence,and ALVE1 is not successfully identified in the reference genome in the upstream and downstream regions of the chicken genome.This study successfully identified the upstream and downstream sequences of ALVE1 in the chicken genome,and in turn verified the location of ALVE1 by extracting CEF cells and DF-1 cell genome.In contrast to the reference genome,we found that the ALVE1 sequence contains a 3'LTR sequence and the insertion position on chicken chromosome 1 is chrl:65,995,534?65,993,540.This study not only provides the complete information of ALVE1 in the chicken genome,but also lays the foundation for further research on the function of ALVE1.2 Study on the expression pattern of long non-coding RNA lnc-ALVE1-AS1 in CEF cells,embryonic early embryo development and early ontogenyIt is known that the long non-coding RNA Inc-ALVE1-AS 1 may be related to innate immunity and individual antiviral ability.This study detected the expression of long non-coding RNA lnc-ALVE1-AS1 in CEF cells,early embryonic development and early ontogeny of chickens.According to the rule,the expression level of the long noncoding RNA lnc-ALVE1-AS1 in the avian leukosis-resistant strain G1 was higher than that of the avian leukemia susceptible strain G3,and the early expression level was higher than the late expression level.This preliminary verification of long non-coding RNA lnc-ALVE1-AS1 may be associated with innate immunity and individual antiviral ability.3 Long-term non-coding RNA lnc-ALVE1-AS1 polymorphism analysis and association with chicken disease resistance phenotypesBy comparing the long non-coding RNA lnc-ALVE1-AS1 sequences of the avian leukemia-resistant line G1 and the susceptible line G3,we found that the sequence of the avian leukosis-resistant line G1 contains a 3-base compared to the sequence of the susceptible line G3.The GCG insertion mutation is presumably related to avian leukemia resistance.In this study,we selected three local breeds such as Huanghuang Chicken,Hainan Wenchang Chicken,and Hebei Macheng Layer Chicken.The amplification of the long non-coding RNA lnc-ALVE1-AS1 sequence was compared with the resistant line G1 and the susceptible line G3.The sequencing sequences of Rugao and Hainan Wenchang chickens were consistent with the resistant line G1 and also contained a 3-base GCG insertion mutation,while the sequence of the Hebei Macheng layer was consistent with the susceptible line G3.Therefore,it is speculated that Rugao Yellow Chicken and Hainan Wenchang Chicken may also be resistant to avian leukemia.A three-base GCG insertion mutation contained in the susceptible line G1 may be associated with avian leukemia resistance was futher verified by the ALVJ challage tests of CEF cells of three local breeds,the results are consistent with the conjecture.In summary,the long non-coding RNA lnc-ALVE1-AS1 may be related to avian leukemia resistance,and it is highly expressed in immune organs at the early stage of ontogeny,and it tends to be down-regulated after being infected with the virus.Resistance line G1 contains a 3-base GCG insertion mutation that may be associated with avian leukemia resistance.