caa a22 4500 465795129 CHVBK 20180323112035.0 cr unu---uuuuu 170327e19900601xx s 000 0 eng 10.1007/BF00308562 doi (NATIONALLICENCE)springer-10.1007/BF00308562 Evolution of the NS genes of the influenza a viruses. II. Characteristics of the amino acid changes in the NS1 proteins of the influenza a viruses [Elektronische Daten] [Katsuhisa Nakajima, Eri Nobusawa, Setsuko Nakajima] We compared the amino acid sequences of the NS1 proteins of human, equine, and avian influenza viruses. The ratios of the amino acid substitutions per nucleotide substitutions in the NS1 proteins were about 27-45%, suggesting the existence of constraints on the amino acid changes of the NS1 protein in evolution. As a measure of constraints exerted on the regions of a protein, a changeability index is proposed. There was a highly conserved region between amino acid residues 30 and 50. The C-terminal region of amino acid residue 165 was a continuously changeable region. We have either introduced several nucleotide substitutions to the NS cDNA of the A/Udorn/72 virus in vitro or constructed the recombinant NS cDNAs between the A/Udorn/72 and A/chick/Japan/24 viruses, and then expressed them in animal cells. We have found that the amino acid substitutions introduced to the low-conserved region of the NS1 protein affected the stability and nuclear localization of the NS1 protein. One of the chimeric proteins between the A/Udorn/72 and A/chick/Japan/24 viruses did not move to the nucleus of the cell and remained in the cytoplasm. Kluwer Academic Publishers, 1990 Influenza A virus nationallicence NS1 protein nationallicence amino acid change nationallicence Nakajima Katsuhisa Department of Virology, Institute of Medical Science, University of Tokyo, Tokyo, Japan aut Nobusawa Eri Department of Virology, Institute of Medical Science, University of Tokyo, Tokyo, Japan aut Nakajima Setsuko Department of Microbiology, Institute of Public Health, Tokyo, Japan aut Virus Genes Kluwer Academic Publishers 4/1(1990-06-01), 15-26 0920-8569 4:1<15 1990 4 11262 https://doi.org/10.1007/BF00308562 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00308562 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nakajima Katsuhisa Department of Virology, Institute of Medical Science, University of Tokyo, Tokyo, Japan aut NATIONALLICENCE 700 1- Nobusawa Eri Department of Virology, Institute of Medical Science, University of Tokyo, Tokyo, Japan aut NATIONALLICENCE 700 1- Nakajima Setsuko Department of Microbiology, Institute of Public Health, Tokyo, Japan aut NATIONALLICENCE 773 0- Virus Genes Kluwer Academic Publishers 4/1(1990-06-01), 15-26 0920-8569 4:1<15 1990 4 11262 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer