Abstract
Human respiratory syncytial viruses (RSVs) are classified into two major groups (A and B) based on antigenic differences in the G glycoprotein. To investigate circulating characteristics and phylodynamic history of RSV, we analyzed the genetic variability and evolutionary pattern of RSVs from 1977 to 2019 in this study. The results revealed that there was no recombination event of intergroup. Single nucleotide polymorphisms (SNPs) were observed through the genome with the highest occurrence rate in the G gene. Five and six sites in G protein of RSV-A and RSV-B, respectively, were further identified with a strong positive selection. The mean evolutionary rates for RSV-A and -B were estimated to be 1.48 × 10–3 and 1.92 × 10–3 nucleotide substitutions/site/year, respectively. The Bayesian skyline plot showed a constant population size of RSV-A and a sharp expansion of population size of RSV-B since 2005, and an obvious decrease 5 years later, then became stable again. The total population size of RSVs showed a similar tendency to that of RSV-B. Time-scaled phylogeny suggested a temporal specificity of the RSV-genotypes. Monitoring nucleotide changes and analyzing evolution pattern for RSVs could give valuable insights for vaccine and therapy strategies against RSV infection.
Highlights
Human respiratory syncytial viruses (RSVs) are classified into two major groups (A and B) based on antigenic differences in the G glycoprotein
Results showed that no recombination occurred between the group of RSV-A and RSV-B (Fig. 1a); in the intragroups, some sequences showed an evidence of mosaicism (Fig. 1b,c), indicating involvement in homologous recombination with identifiable parental
Following the performance of single nucleotide polymorphism (SNP) calling in the genes of both RSV-A and -B, a large number of Single nucleotide polymorphisms (SNPs) were found in their genomes, indicating a high level of genetic diversity of RSVs
Summary
Human respiratory syncytial viruses (RSVs) are classified into two major groups (A and B) based on antigenic differences in the G glycoprotein. Human respiratory syncytial virus (RSV) is a major cause of serious lower respiratory tract illness in infants, young children and the elderly in both industrialized and developing c ountries[1] It belongs to the genus Orthopneumovirus, family Pneumoviridae, with a nonsegmented, negative-sense RNA genome of approximately 15,200 nucleotides that contains genes and encodes proteins. G protein is the most variable protein[4], it has two hypervariable regions flanking the highly conserved central region, and the hypervariable regions contain most antigenic differences both in the inter- and intra-group of the virus, with the C-terminal or the second hypervariable region encompasses the strain-specific epitopes[5], commonly sequenced to determine the genotype (strain or clade) or investigate genetic diversity of RSV s trains[6,7,8]. It was strongly suggested that selective pressures are continuing to drive the evolution of RSV, genetically and College of Life Sciences and Bioengineering, Beijing Jiaotong University, Beijing 100044, China. *email: jshhe@ bjtu.edu.cn
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
