Yamashita M, Krystal M, Fitch W M, Palese P
Department of Microbiology, Mount Sinai School of Medicine, City University of New York, New York 10029.
Virology. 1988 Mar;163(1):112-22. doi: 10.1016/0042-6822(88)90238-3.
Sequence analyses and comparison of the genes coding for the nonstructural (NS) and hemagglutinin (HA) proteins of different influenza B viruses isolated between 1940 and 1987 reveal that the number of substitutions is not always proportional to the time between isolates. Examination of 14 influenza B virus NS gene and 10 HA gene sequences by the maximum parsimony method suggested that--as with influenza C viruses--there are multiple evolutionary lineages which can coexist for considerable periods of time. Comparison of the sequence divergence among genes of viruses belonging to type A, B, and C virus suggests that, in man, influenza B viruses evolve slower than A viruses and faster than C viruses. We propose an evolutionary model for influenza B viruses that is intermediate between the pattern for human influenza A viruses and that for influenza C viruses.
对1940年至1987年间分离出的不同乙型流感病毒的非结构（NS）蛋白和血凝素（HA）蛋白编码基因进行序列分析和比较，结果显示，替换数并不总是与分离株之间的时间成正比。通过最大简约法对14个乙型流感病毒NS基因序列和10个HA基因序列进行分析表明，与丙型流感病毒一样，存在多个进化谱系，它们可以共存相当长的时间。对甲型、乙型和丙型流感病毒的基因序列差异进行比较表明，在人类中，乙型流感病毒的进化速度比甲型流感病毒慢，比丙型流感病毒快。我们提出了一种乙型流感病毒的进化模型，该模型介于人类甲型流感病毒和丙型流感病毒的模式之间。
