TAS1 trans-acting siRNA targets are differentially regulated at low temperature, and TAS1 trans-acting siRNA mediates temperature-controlled At1g51670 expression.
To endure considerable fluctuations in temperature, plants need precise regulation of temperature-controlled gene expression. In this study, the involvement of TAS1 trans-acting siRNA (tasiRNA) in temperature-controlled gene expression was examined in Arabidopsis. The accumulation of TAS1 tasiRNA was downregulated at 4 degrees C. Concomitant with the reduction of TAS1 tasiRNA-mediated cleavage, expression of At1g51670, a target of TAS1 tasiRNA, was upregulated at 4 degrees C in the wild type but not in a dicer-like enzyme (DCL) 4 mutant (dcl4-2), which is impaired in tasiRNA biogenesis. The expression of At4g29760 and of At5g18040, further TAS1 tasiRNA targets, was upregulated both in the wild type and in dcl4-2 at 4 degrees C. However, after shifting the temperature to 22 degrees C, low-temperature-induced expression of At4g29760 rapidly dropped in the wild type, but not in dcl4-2. Thus TAS1 tasiRNA acted as a sweeper for the clearance of excess amounts of At4g29760 transcripts. Our data suggest that differential regulation of TAS1 tasiRNA targets is involved in temperature-controlled gene expression.
Kume
Kohei
K
United Graduate School of Agricultural Sciences, Iwate University.
Tsutsumi
Ken-Ichi
K
Saitoh
Yasushi
Y
D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics*; D013696:Temperature
D029681:Arabidopsis Proteins; C553599:At1g51670 protein, Arabidopsis; D012333:RNA, Messenger; D034741:RNA, Small Interfering