Abstract
Using CRES-T system, we isolated transgenic Arabidopsis which exhibited tolerance to salt and osmotic stresses. We selected transcription factors in which expression was responsed to these stimuli, we converted them to chimeric repressor by fusion with repression domain (SRDX) and expressed them in Arabidopsis. The seedlings of 35S:AtMYB102-SRDX, 35S:ANAC047-SRDX and 35S:GARP-SRDX survived on MS plate containing 225 mM NaCl, under which condition wild-type Arabidopsis were unable to be alive.
Chimeric repressors against ZAT6 and AtERF5 exhibited tolerance to osmotic stress since both transgenic plants sustained viability even at high concentration of mannitol, 650 mM where most of all plants could not survive and germinate. Microarray analysis showed that chimeric AtMYB102 repressor enhanced expression of stress responsible genes such as DREB1A and TINY genes and suppressed expression of ZAT11 and AtMYB15. We will discuss a mechanism of improving plants on abiotic stresses and possibility for agricultural application.
