Hamid-Reza Amini - Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, Karaj
Abbas Pakdel - Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, Karaj
Hossein Moradi Shahr-Babak - Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, Karaj
Shahin Eghbalsaeid - Department of Animal Science, Khorasgan Branch, Islamic Azad University, Isfahan, Iran.

In the recent years, making the genetically modified organisms has been one of the most endeavor research fields. Among animal models, transgenic birds are one of the major candidates for production of biopharmaceutical proteins. In recent studies conducted by the present authors, nuclease properties of egg albumen as a possible biological barrier that couldattenuate chicken transgenesis efficiency through SMGT approach and transfection of blastoderm cells were identified.Therefore, the aim of this study was to compare the nuclease activity of egg albumen With the DNase I enzyme, as acommercial enzyme that digesting DNA. In order to eliminate the possible differences in the amount of egg white nucleaseproperties between eggs, egg albumen from ten eggs was pooled. Then, one μg of pDB2 plasmid, were incubated with different ratio of chicken egg white in a fixed volume of 100 and then 300 μl, and as well as incubated with 1 unit of DNase I enzyme, at 37 ° C for 30 minutes. After that, the phenol-chloroform mixture were used for isolation of nucleic acids fromthe protein component of egg white, and in order to compare the band patterns, a fixed amount of supernatant was loadeddirectly onto a 1% agarose gel. According to the qualitative assessment performed in relation to comparison of nuclease activity in chicken egg white and DNase I enzyme, the results indicated that, the nuclease activity of 250-300 μl of chicken egg albumen is equivalent to 1 unit of nuclease activity of DNase I enzyme.

Egg albumen, Nuclease Activity, DNase I enzyme, pDB2 Plasmid, Transgenesis