[Demonstration of the influenza virus A RNA by nucleic acid molecular hybridization using biotin-treated probes]

A probe containing full-size DNA copy of influenza A/USSR/90/70 virus protein gene M labeled with biotin on 32P was used for influenza A virus RNA detection by dot hybridization method. For labeling with biotin, a new method of its administration by chemical modification of nucleic acid was employed. In homologous DNA:DNA hybridization the sensitivity of determinations was less than 1 pg in the biotin-treatment of the probe and 1.25 pg in its radioactive labeling. Hybridization of DNA probe with cytoplasmic RNA isolated from influenza A virus-infected (strains A/USSR/90/77 and A/Texas/77) MDCK cells revealed RNA in the dot corresponding to 4.5-5.5 1g ID50 of virus present in 2 x 10(4) cells. The probe did not bind with negative controls in any dot in all the tests. The results of the study indicate that DNA probes labeled with biotin and 32P and used in dot hybridization for influenza A virus RNA detection in infected cells show the similar sensitivity and specificity.