Gp85 genetic diversity of avian leukosis virus subgroup J among different individual chickens from a native flock

Abstract

To compare the genetic diversity and quasispecies evolution of avian leukosis virus (ALV) among different individuals, 5 chickens, raised in Shandong Provice of China, were randomly selected from a local chicken flock associated with serious tumor cases. Blood samples were collected and inoculated into chicken embryo fibroblast and DF-1 cell lines for virus isolation and identification, respectively, of Marek's disease virus (MDV), reticuloendotheliosis virus (REV), and ALV. Five strains of ALV subgroup J (ALV-J) were identified, and the gp85 gene from each strain was amplified and cloned. For each strain, about 20 positive clones of gp85 gene were selected for sequence analyses and the variability of the quasispecies of the 5 strains was compared. The results showed that the nuclear acid length of gp85 gene of 5 ALV-J isolates is 921 bp, 921 bp, 924 bp, 918 bp, and 912 bp respectively, and amino acid homologies of different gp85 clones from the 5 ALV-J strains were 99.3 to 100%, 99.3 to 100%, 99.4 to 100%, 98.4 to 100%, 99.0 to 100%, respectively. The proportions of dominant quasispecies were 65.0%, 85.0%, 85.0%, 50.0%, 84.2%, respectively, and homology of the gp85 among these dominant quasispecies was 89.2 to 92.5%. These data demonstrated the composition of the ALV-J quasispecies varied among infected individuals even within the same flock, and the dominant quasispecies continued to evolve both for their proportion and gene mutation.

Full-length cDNA sequence analysis of 85 avian leukosis virus subgroup J strains isolated from chickens in China during the years 1988–2018: coexistence of 2 extremely different clusters that are highly dependent upon either the host genetic background or the geographic location

“…This may be because of the instability and diversity of the Retroviridae ( Garcia-Montojo et al., 2018 ) and the rapid evolution of the virus to help it escape the immune protection mechanisms of the host by the gene mutations and reorganization of the genome ( Zhang et al., 2018 ). During the process of ALV-J transmission and spread all over the world, the ALV-J genome is constantly changing ( Ji et al., 2012 , Li et al., 2016 ).…”

Characterization of subgroup J avian Leukosis virus isolated from Chinese indigenous chickens

“…Lin [ 27 ] isolated 12 strains of avian leukosis virus subgroup J from chickens in south China during 2013–2014 and detected several amino acid variations and potential glycosylation sites in gp85 by sequencing. In addition, they found that many genetic variations of the gp85 exist in an indigenous chicken flock [ 17 ]. The monitoring of ALV in local chickens in our country has been continuous; simultaneous, our laboratory has executed the purification of ALV-J from indigenous chickens.…”

“…A measure of success has been achieved in the purification, prevention, and control of ALV among white-feathered broilers and layer chickens since the purification of ALV was executed in China. But there are many breeds with excellent characteristics in China, these chickens are still susceptible to ALV-J infection [ 17 , 18 ].Thus, to grasp the quasispecies evolution of ALV in a flock of chickens of local breed and accelerate the purification of ALV in China, this study isolated and identified the viruses from a local chicken farm during the process of purifying ALV and the molecular characteristics of env and LTR were determined and analyzed.…”

Roles of MOV10 in Animal RNA Virus Infection

“…RNA viruses are also divided into avian, mammalian, and zoonotic viruses in domestic animal industries. For example, the avian leukosis retrovirus causes great losses in the avian industry and many subgroups have been isolated in recent years (6)(7)(8)(9)(10)(11)(12). In mammals, more RNA viruses are also being reported, of which the classical swine fever virus and porcine reproductive and respiratory syndrome virus (PRRSV) are the main RNA viruses that cause great losses in porcine industries.…”