Production of transgenic quails with high frequency of germ-line transmission using VSV-G pseudotyped retroviral vector

We report here the production of transgenic quails using a replication-defective pantropic retroviral vector based on Moloney murine leukemia virus (MoMLV) pseudotyped with vesicular stomatitis virus G protein (VSV-G). The retroviral vector was injected into laid quail embryos at the blastodermal stage, and the embryos were incubated to hatch to produce G₀ transgenic quails. Among 134 embryos subjected to viral injection, 37 hatched. The viral vector sequence was detected in the tissues of all Go quails. The germ-line transmission efficiency of Go quails mated with non-transgenic quails was more than 80% on average. Southern blot analysis revealed that the G₁ transgenic progeny had one to three copies of the transgene. The expression of vector-encoded neomycin-resistance gene under the control of the Rous sarcoma virus (RSV) promoter was observed in several tissues including heart and muscle of both G₁ and G₂ transgenic offspring. Due to the high frequency of germ-line transmission, this method may markedly facilitate the production of transgenic avian.