Vm. Blinov et al., ANALYSIS OF GENE RECOMBINATION ACTIVITY O F ANIMAL INFLUENZA-VIRUS HEMAGGLUTININ GENES IN THE PROCESS OF THEIR ADAPTATION TO A NEW HOST, MAN, Voprosy virusologii, 38(6), 1993, pp. 263-268
The authors tried to decode the mechanism of influenza viruses species
adaptation in the process of host changing. The functionally importan
t replacement in the surface pocket domains were revealed, particularl
y in the conservative region 221-241, involving fibronectin-like part.
Close replacements were revealed in the region 141-161. The method of
construction of heteroduplexes between hemagglutinin RNA of duck, pig
, and human viruses was used. The method showed that all heteroduplexe
s formed recombinogene structures. An unexpected effect of directional
recombination was elicited for hemagglutinin RNA heteroduplexes in ca
ses of duck-pig and human-pig viruses. During the directional recombin
ation the following processes took place: the receptor-binding site of
animal type was transmitted to the duck virus, while the human recept
or-binding site was transmitted to the pig virus. According to the exp
erimental data, a new hypothesis is formulated: the cascade mechanism
of directional recombination for duck, animal and human viruses makes
it' possible for the recombinant viruses to overcome interspecies barr
iers.