Characterization of a nonradioactive cloned cDNA probe for detecting avian reoviruses

Avian reoviruses (ARVs) cause important losses in the poultry industry. Improved tests are needed for diagnosis of ARV infections. A cDNA library was prepared from the S1133 isolate of ARV. EcoRI-adaptored cDNA molecules were ligated into the plasmid pUC19 and used to transform Escherichia coli strain DH5 alpha MCR. One cDNA clone was selected and designated HJp1. The HJp1 was labeled by random priming with digoxigenin-dUTP. This cDNA probe hybridized with the S1 gene fragment of the ARV S1133 strain in northern blot hybridization. The probe detected ARV isolates in dot-blot hybridization assays. The probe did not cross-hybridize with nucleic acids extracted from mock-infected chicken embryo fibroblast cells or unrelated avian viruses. Probe HJp1 detected as little as 0.78 ng of ARV RNA.