Table 2. Selected statistically significant polymorphic sites and their potential function or structural insights.
Protein | Site | Residues | Effect | Location/Potential Effect |
---|---|---|---|---|
PB2 | 358 | E, V | Residue only | Cap-binding domain (318-483 aa)37 |
649 | V, I | Residue only | Host-specific domain (538-678 aa)39 | |
199 | A, T | Residue and host | Genomic marker between avian and human IAVs17 | |
PB1-F2 | 75 | H, L, R | Residue and host | Part of a positively charged subdomain required for the localization of full-length peptide to mitochondria18 |
PA | 323 | V, I | Host-residue interaction | Compensate for the variation at site 545 to stabilize the molecule |
545 | I, V | Residue only | Compensate for the variation at site 323 to stabilize the molecule | |
187 | L, I | Residue and host | N-terminal endonuclease domain of PA (1-196 aa)50 | |
HA | 173 | N, T | Residue and host | Sa antigenic site51 |
203 | N, S | Residue only | Sb antigenic site51 | |
NS1 | 7 | S, L, T | Residue only | dsRNA binding domain52 |
27 | I, M | Residue only | dsRNA binding domain52 | |
101* | D, E | Residue only | Interacts with the PI3K-inhibitory domain; might act as nuclear export signal and key residue for the NS1-CPSF30 interaction in H5N1 viruses53 | |
103* | F, Y | Residue only | Interacts with the PI3K-inhibitory domain, increase in IFN antagonism when tested in H5N1 background54 | |
118* | R, K | Residue only | Allows closer packing of the PI3K helix to the NS1 protein | |
227 | E, G | Residue and host | PDZ-binding motif; genomic marker between avian and human IAVs17 | |
NEP | 7 | S, L, T | Residue only | protease-sensitive N-terminaldomain21; function unknown |
70 | S, G | Residue and host | M1 binding domain21; genomic marker between avian and human IAVs17 | |
64* | K, T | Residue only | M1 binding domain21; increases the negative charge of the M1-binding domain | |
86* | R, I | Residue only | M1 binding domain21; increases the negative charge of the M1-binding domain | |
88* | K, T | Residue only | M1 binding domain21; increases the negative charge of the M1-binding domain |
These positions were based on the sequences used in this study.
*The polymorphic sites with underlying allele effect.