Use of ANP32 protein in maintaining the polymerase activity of influenza virus in hosts

An isolated mutated acidic leucin-rich nuclear phosphoprotein 32 (ANP32) protein resulting from subjecting a wild type ANP32 protein to one or more mutations selected from the group consisting of:

• the amino acid at position 129 substituted with isoleucine (I), lysine (K), aspartic acid (D), valine (V), proline (P), tryptophan (W), histidine (H), arginine (R), glutamine (Q), glycine (G), or glutamic acid (E);
• the amino acid at position 130 substituted with asparagine (N), phenylalanine (F), lysine (K), leucine (L), valine (V), proline (P), isoleucine (I), methionine (M), tryptophan (W), histidine (H), arginine (R), glutamine (Q), or tyrosine (Y);
• the amino acids at positions 60 and 63 are both substituted with alanine (A);
• the amino acids at positions 87, 90, 93 and 95 are all substituted with alanine (A);
• and
• the amino acids at positions 112, 115 and 118 are all substituted with alanine (A);
• wherein:
• the wild type ANP32 protein is wild type ANP32A or ANP32B derived from chicken, human, zebra finch, duck, turkey, pig, mouse or horse;
• when the wild type ANP32 protein is chicken ANP32B protein, duck ANP32B protein or turkey ANP32B protein, the amino acid at position 129 of the mutated ANP32 protein is not isoleucine (I) and the amino acid at position 130 of the mutated ANP32 protein is not asparagine (N);
• when the wild type ANP32 protein is human ANP32A protein, the amino acid at position 130 of the mutated ANP32 protein is not asparagine (N);
• when the wild type ANP32 protein is mouse ANP32A protein, the amino acid at position 130 of the mutated ANP32 protein is not alanine (A);
• when the wild type ANP32 protein is an ANP32A protein, the amino acid positions correspond to the amino acid positions of a chicken ANP32A protein of GenBank No. XP_413932.3;
• and
• when the wild type ANP32 protein is an ANP32B protein, the amino acid positions correspond to the amino acid positions of the human ANP32B protein of GenBank No. NP_006392.1.