Abstract
Tobacco ETHYLENE-RESPONSIVE FACTOR3 (ERF3) is a member of the ERF domain transcription factors and has an ability of downregulation of transactivation of other ERFs. To analyze the protein stability of ERF3 in vitro, we added the recombinant ERF3 into the crude extract from cultured cells and observed rapid degradation of the recombinant ERF3. To study the protein stability of ERF3 in plant cells, we prepared the transgenic callus in which over-expressed GFP-ERF3 gene but detected no fluorescence of GFP-ERF3. By contrast, the ERF domain and the repression domain were stable in vitro and in transgenic callus. These results suggest that ERF3 is an unstable protein and the ERF domain and the repression domain are not involved in the regulation of instability of ERF3 in consistent with the previous results that these two domains were not required for the interaction of ERF3 with NtUBC2.
