Specific expression of vacuolar AtOCTs during drought, cold and salt stress. A) Expression of AtOCTs in response to drought stress. Expression was monitored in seedlings at indicated time points by RNA-Gel-blot analysis. 20 minutes after initiation of desiccation transcripts of AtOCT4 5and 6 start to accumulate over a period of 8 hours, with a maximum around 2–4 hours. AtOCT5 and AtOCt6 respond with a strong accumulation of transcripts whereas AtOCT2 and AtOCT3 do not respond at all. B) Expression of AtOCTs in response to cold stress. Expression was monitored in seedlings at indicated time points by RNA-Gel-blot analysis after transfer of seedling to 4°C. Increased levels of transcript were found 20 minutes after induction for AtOCT3 and AtOCT5 with a transient increase over 2 hours and decreasing after 4 hours. AtOCT2, 4 and 6 do not respond to cold stress. C) Expression of AtOCTs in respond to salt stress. Transcripts of AtOCT4, 5 and 6 respond to salt stress, AtOCT5 and AtOC6 expression shows a maximum level of transcripts after 6 hours and AtOCT4 after 24 hours. The expression of AtOCT2 and 3 does not respond to salt stress.