Expression of an Episomal Vector in Developing Chicken Embryo and Chicks

The domesticated chicken has important roles in basic and applied research. The vector based on scaffold matrix attachment region (S/MAR) appears to be sufficient to maintain long-term expression in an episomal state in various mammalian cells. To explore the practical use of episomal vector in transgene technology of agricultural chickens, we fused the S/MAR of the human β-interferon gene into the pEGFP vector and transduced it into chickens by sperm-mediated gene transfer (SMGT). PCR detection indicated the positive rate of transgene chickens was 60%. The RT-PCR detection and fluorescence observation confirmed the expression of the GFP and indicated the existence of the GFP during the chicken embryogenesis and fetal development. The PCR detection and rescue experiments confirmed the episomal state of the pEPI-EGFP in chick embryos and chicks. These results showed that the S/MAR-based vector could function properly in chicken embryos and was a practicable tool combined with the SMGT to study the development of chickens.