Expression Profile of Immune-Associated Genes in the Kidney of Cultured Large Yellow Croaker Larimichthys crocea in the East China Sea Area

To explore the effect of environment conditions on immune activity of fish, eight immune-associated genes responsible for innate immunity were selected from the Gen Bank, i.e. Pgrn-a, Ifit2, P-hepcidin, Lect2, β2m, Irf1, Il25 and Hsp96, and the m RNA expressions of them in the kidney of cultured large yellow croaker Larimichthys crocea in different sea areas in the East China Sea were examined with q PCR techniques. In the contrasts of immune-associated gene expression between areas and populations, significant differences were found, expression levels of these immune-associated genes were lower in the clear water area than in the poor water quantity area, and lower in May than in October. MY was more sensitive to environmental factors than DQ, which was coincident with the water quality in the culturing areas. Differential analyses of the expression levels of these immune-associated genes showed that significant up-regulation could be triggered by poor environmental factors. The expression patterns indicated that the expression levels of these genes were sensitive to ecological changes, thereby the immune-associated genes, especially Pgrn-a, Ifit2, β2m, Il25 and Hsp96, might serve as immediate and sensitive indicators of population immunologic vigor and ecosystem health. But the expression of immunity-associated genes at the level of gene transcription is highly influenced by multiple factors, and the exact causes or influencing factors of the up-regulation or down-regulation of these genes still need further thorough investigation.

The spatiotemporal analysis of SARS-CoV-2 transmission in China since the termination of the dynamic zero-COVID policy

China's dynamic zero-COVID policy has effectively curbed the spread of SARS-CoV-2,while inadvertently creating immunity gaps within its population.Subsequent surges in COVID-19 cases linked to various SARS-CoV-2 lineages post-policy termination necessitate a thorough investigation into the epidemiological landscape.This study addresses this issue by analyzing a comprehensive dataset of 39,456 high-quality genomes collected nationwide over an 11-month period since policy termination.Through lineage assignment,phylogenetic analysis,pandemic pattern comparison,phylodynamic reconstruction,and recombination detection,we found that China's postepidemic period could be divided into three stages,along with dynamic changes in dominant lineages.Geographical clustering of similar lineages implies the importance of cross-border cooperation among neighboring regions.Compared to the USA,UK,and Japan,China exhibits unique trajectories of lineage epidemics,characterized by initial lagging followed by subsequent advancement,indicating the potential influence of diverse prevention and control policies on lineage epidemic patterns.Hong Kong,Shanghai,and Hubei emerge as pivotal nodes in the nationwide spread,marking a shift in the transmission center from east to central regions of China.Although China hasn't experienced significant variant emergence,the detection and validation of the novel recombination event,XCN lineage,underscore the ongoing virus evolution.Overall,this study systematically analyzes the spatiotemporal transmission of SARS-CoV-2 virus in China since the termination of the dynamic zeroCOVID policy,offering valuable insights for regional surveillance and evidence-based public health policymaking.