作者： Zhiqiang Duan1,2,*,Haiying Shi 1,2,Jingru Xing 1,2,Qianyong Zhang 1,2 and Menglan Liu1,2
期刊：INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES（IF=6.2，中科院2区）
发表年份：2023
摘要：The matrix (M) protein of Newcastle disease virus (NDV) contains large numbers of unevenly distributed basic residues, but the precise function of most basic residues in the M protein remains enigmatic. We previously demonstrated that the C-terminus (aa 264–313) of M protein interacted with the extra-terminal (ET) domain of chicken bromodomain-containing protein 2 (chBRD2), which promoted NDV replication by downregulating chBRD2 expression and facilitating viral RNA synthesis and transcription. However, the key amino acid sites determining M’s interaction with chBRD2/ET and their roles in the replication and pathogenicity of NDV are not known. In this study, three basic residues—R283, R286, and K288—in the NDV M protein were verified to be responsible for its interaction with chBRD2/ET. In addition, mutation of these basic residues (R283A/R286A/K288A) in the M protein changed its electrostatic pattern and abrogated the decreased expression of endogenic chBRD2. Moreover, a recombinant virus harboring these mutations resulted in a pathotype change of NDV and attenuated viral replication and pathogenicity in chickens due to the decreased viral RNA synthesis and transcription. Our findings therefore provide a better understanding of the crucial biological functions of M’s basic residues and also aid in understanding the poorly understood pathogenesis of NDV.