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Molecular #patterns of #matrix protein 1 (M1): A strong predictor of adaptive #evolution in #H9N2 avian #influenza viruses

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By G.M.

Significance

The dominance of the H9N2 subtype of avian influenza virus (AIV) within the influenza A virus family has raised questions regarding the factors influencing its epidemiological dominance. This study concentrates on the role of five major evolutionary patterns of the matrix protein M1 in the replication and transmission of H9N2 AIVs. The findings indicate a strong correlation between the epidemiological dominance of H9N2 AIVs and the specific M1 patterns, particularly M1P5. It highlights the significance of genetic patterns in M1 for understanding the adaptive differences and turnover of epidemiological dominant H9N2 AIVs.


Abstract

The H9N2 subtype of avian influenza virus (AIV) emerges as a significant member of the influenza A virus family. However, the varying degrees of epidemiological dominance among different lineages or clades of H9N2 AIVs have not been fully clarified. The matrix protein M1, a key structural component of the virion, plays a crucial role in maintaining the viral structure and lifecycle. To elucidate the intrinsic relationship between the genetic patterns of M1 and the adaptive dynamics of H9N2 AIVs, this study focused on the five major evolutionary patterns of M1 and conducted in vitro and in vivo investigations from the perspectives of vRNP release after viral uncoating, polymerase activity, mRNA and vRNA levels, the nuclear export of vRNPs, plasma membrane–binding capacity, proliferation capacity, growth competitiveness, and transmission potential. The results revealed a strong correlation between the epidemiological dominance of H9N2 AIVs and the specific patterns of M1, with M1P5 standing out as particularly significant. This finding highlights the pivotal influence of the M1 gene patterns on the replication and transmission dynamics of H9N2 AIVs, thereby offering valuable insights into the mechanisms driving differences in adaptive evolution and shifts in epidemiological dominance within the H9N2 AIV population.

Source: Proceedings of the National Academy of Sciences of the United States of America, https://www.pnas.org/doi/10.1073/pnas.2423983122

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