The Preliminary Study On The Construction Of Exogenous Gene Specific Deletion System In Transgenic Rice Endosperm Using DsRed2

For the construction of highly-efficient exogenous gene specific-deletion system in transgenic rice endosperm. The expression of exogenous red fluorescent protein in transgenic rice was verified by using the p1300ActRedTnos-transformed rice and p1300Gt1RedTnos-transformed rice. The results of RFP detection proved that the red fluorescent protein (DsRed2) was a feasible repoter gene for dedection of the excision efficiency.According to the preference of rice genetic codon, the three recombinase gene Crein, CreM and Flp were modified and re-synthesis. The endosperm-spefic promoter Gt1 was used to control the recombinase gene, the fusion LoxP/Frt sequence were used as recognition sites and DsRed2 as the repoter gene. Six expression vector for auto-deletion system and five expression vector for cross-deletion system have been contructed completely, and their corresponding clones have been acquired. The RFP detection of the seeds of T0 progeny of p1300LF-ART-GFT-transformed rice (DsRed2 is expressed in other organs but not in endosperm) and p1300ART-LF-GFT-transformed rice (DsRed2 is expressed in endosperm but not in other organs) showed that the excision were occored in endosperm. Preliminary speculated that recombinase Flp can mediate the deletion of exogenous gene in endosperm. But it is not clear whether the deletion was completely, the analysis of the excision efficient need to be further verified.