Equine ANP32 proteins support influenza A virus RNA polymerase activity  

作　　者：Yuan Zhang Xing Guo Mengmeng Yu Liuke Sun Yuxing Qu Kui Guo Zhe Hu Diqiu Liu Haili Zhang Xiaojun Wang 

机构地区：[1]State Key Laboratory for Animal Disease Control and Prevention,Harbin Veterinary Research Institute,The Chinese Academy of Agricultural Sciences,Harbin,150069,China [2]State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases,Key Laboratory for Zoonosis Research of the Ministry of Education,Institute of Zoonosis and College of Veterinary Medicine,Jilin University,Changchun,130062,China

出　　处：《Virologica Sinica》2023年第6期951-960,共10页中国病毒学（英文版）

基　　金：the National Natural Science Foundation of China to HL Zhang(32002275);Natural Science Foundation of Heilongjiang Province of China to HL Zhang(YQ2020C021).

摘　　要：Host ANP32 family proteins are crucial for maintaining the activity of influenza RNA polymerase and play an important role in the cross-species transmission of influenza viruses.To date,the molecular properties of equine ANP32(eqANP32)protein are poorly understood,particularly the mechanisms that affect equine influenza virus(EIV)RNA polymerase activity.Here,we found that there are six alternative splicing variants of equine ANP32A(eqANP32A)with different levels of expression.Further studies showed that these six splicing variants of eqANP32A supported the activity of EIV RNA polymerase to varying degrees,with the variant eqANP32A_X2 having the highest expression abundance and exhibiting the highest support of polymerase activity.Sequence analysis demonstrated that the differences in the N-Cap regions of the six splicing variants significantly affected their N-terminal conformation,but did not affect their ability to bind RNA polymerase.We also demonstrated that there is only one transcript of eqANP32B,and that this transcript showed only very low support to the EIV RNA polymerase.This functional defect in eqANP32B is caused by the sequence of the 110–259 amino acids at its Cterminus.Our results indicated that it is the eqANP32A_X2 protein that mainly determines the efficiency of the EIV replication in horses.In conclusion,our study parsed the molecular properties of eqANP32 family proteins and revealed the sequence features of eqANP32A and eqANP32B,suggesting for the first time that the N-Cap region of ANP32A protein also plays an important role in supporting the activity of the influenza virus polymerase.

关 键 词：Equine influenza virus(EIV) Equine ANP32A Equine ANP32B RNA polymerase activity N-Cap domain 

分 类 号：R563.1[医药卫生—呼吸系统]