Involvement of elevated proline accumulation in enhanced osmotic stress tolerance in Arabidopsis conferred by chimeric repressor gene silencing technology.

Arabidopsis plants transformed with a chimeric repressor for 6 transcription factors (TFs), including ADA2b, Msantd, DDF1, DREB26, AtGeBP, and ATHB23, that were converted by Chimeric REpressor gene Silencing Technology (CRES-T), show elevated salt and osmotic stress tolerance compared with wild type (WT) plants. However, the roles of TFs in salt and osmotic signaling remain largely unknown. Their hyper-osmotic stress tolerance was evaluated using 3 criteria: germination rate, root length, and rate of seedlings with visible cotyledons at the germination stage.

Identification of Chimeric Repressors that Confer Salt and Osmotic Stress Tolerance in Arabidopsis.

We produced transgenic Arabidopsis plants that express chimeric genes for transcription factors converted to dominant repressors, using Chimeric REpressor gene-Silencing Technology (CRES-T), and evaluated the salt tolerance of each line. The seeds of the CRES-T lines for ADA2b, Msantd, DDF1, DREB26, AtGeBP, and ATHB23 exhibited higher germination rates than Wild type (WT) and developed rosette plants under up to 200 mM NaCl or 400 mM mannitol. WT plants did not grow under these conditions.