Induction of Dormancy in Arabidopsis Summer Annuals Requires Parallel Regulation of DOG1 and Hormone Metabolism by Low Temperature and CBF Transcription Factors
Induction of Dormancy in Arabidopsis Summer Annuals Requires Parallel Regulation of DOG1 and Hormone Metabolism by Low Temperature and CBF Transcription Factors
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DOI：
10.1105/tpc.111.087643
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发表时间：
2011-07-01
期刊：
影响因子：
11.6
通讯作者：
Penfield, Steven
中科院分区：
文献类型：
--
作者：
Kendall, Sarah L.;Hellwege, Anja;Penfield, Steven
夏季一年生植物在土壤种子库中以种子越冬。这是由冷诱导的休眠增加种子成熟过程中，随后由种子吸胀过程中的状态，其中冷，而不是促进发芽开关。在这里，我们表明，在拟南芥种子成熟转录组是高度温度敏感性，并揭示，种子成熟过程中的低温诱导与休眠相关的几个基因，包括延迟发芽1（DOG 1），并影响成熟种子中的赤霉素和脱落酸水平。缺乏DOG 1或具有改变的赤霉素或脱落酸合成或信号传导的突变体反过来显示响应于低种子成熟温度而进入深度休眠状态的能力降低。此外，我们发现DOG 1在成熟过程中促进赤霉素催化。我们表明，C-重复结合因子（CBFs）是必要的调节休眠和GA 2 OX 6和DOG 1的表达引起的低温。然而，CBF转录的温度敏感性显着降低种子和不存在吸胀种子。我们的数据表明，CBF表达的抑制可能是一个关键的功能，允许冷促进而不是抑制发芽，并支持一个模型，其中CBF的行为平行于低温信号通路的调节休眠。
Summer annuals overwinter as seeds in the soil seed bank. This is facilitated by a cold-induced increase in dormancy during seed maturation followed by a switch to a state during seed imbibition in which cold instead promotes germination. Here, we show that the seed maturation transcriptome in Arabidopsis thaliana is highly temperature sensitive and reveal that low temperature during seed maturation induces several genes associated with dormancy, including DELAY OF GERMINATION1 (DOG1), and influences gibberellin and abscisic acid levels in mature seeds. Mutants lacking DOG1, or with altered gibberellin or abscisic acid synthesis or signaling, in turn show reduced ability to enter the deeply dormant states in response to low seed maturation temperatures. In addition, we find that DOG1 promotes gibberellin catabolism during maturation. We show that C-REPEAT BINDING FACTORS (CBFs) are necessary for regulation of dormancy and of GA2OX6 and DOG1 expression caused by low temperatures. However, the temperature sensitivity of CBF transcription is markedly reduced in seeds and is absent in imbibed seeds. Our data demonstrate that inhibition of CBF expression is likely a critical feature allowing cold to promote rather than inhibit germination and support a model in which CBFs act in parallel to a low-temperature signaling pathway in the regulation of dormancy.