Phytochrome interacting factors (PIFs) are essential regulators for sucrose-induced hypocotyl elongation in Arabidopsis
Phytochrome interacting factors (PIFs) are essential regulators for sucrose-induced hypocotyl elongation in Arabidopsis
复制标题
光敏色素相互作用因子（PIF）是拟南芥中蔗糖诱导下胚轴伸长的重要调节因子
DOI：
10.1016/j.jplph.2011.04.009
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发表时间：
2011-10-15
影响因子：
4.3
通讯作者：
Bi, Yurong
中科院分区：
文献类型：
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作者：
Liu, Zhongjuan;Zhang, Yongqiang;Bi, Yurong
光敏色素相互作用因子（Phytochrome interacting factors，PIFs）是碱性螺旋-环-螺旋转录因子的一个亚家族，在正常条件下是下胚轴伸长的正调控因子。在这里，我们表明PIF 1，3，4，5一起发挥核心作用，在蔗糖诱导下胚轴伸长。当幼苗生长在光下转移到黑暗中，外源施加蔗糖显着诱导下胚轴伸长野生型Col-0，但这种效果受损的所有测试的突变体，特别是在四重突变pif 1 pif 3 pif 4pif 5（pifq）。随后的实验表明，在不同的光/暗（L/D）循环条件下，蔗糖仍然显着诱导Col-0下胚轴的伸长，但表现出对pifq的影响不大。植物激素赤霉素（GA）已被证明是蔗糖诱导的下胚轴伸长所需的，但GA（3）（GA的活性形式）的应用不能挽救在pifq中观察到的损伤，这表明在pifq中蔗糖诱导的下胚轴伸长的损伤不是由于内源GA减少。有趣的是，通过RT-PCR检测，我们发现蔗糖在黑暗中上调了PIF 1，3，4，5的转录水平。此外，这种效果依赖于GAs的存在。此外，在连续光照条件下，蔗糖明显抑制Col-0下胚轴的伸长，但对pifq没有影响，而外源GA（3）可以恢复Col-0下胚轴的抑制，但对pifq的影响很小。这些结果共同表明，PIFs与GAs一起控制蔗糖对拟南芥幼苗下胚轴伸长的影响。(C)2011年Elsevier GmbH。All rights reserved.
Phytochrome interacting factors (PIFs) are members of a subfamily of basic helix-loop-helix transcript factors and have been proposed to act as positive regulators of hypocotyl elongation under normal condition. Here, we show that PIF1, 3,4, 5 together play a central role in sucrose-induced hypocotyl elongation. When seedlings grown in light were transferred to darkness, exogenously applied sucrose significantly induced hypocotyl elongation in wild type Col-0, but this effect was impaired in all tested Of mutants, especially in the quadruple mutant pif1pif3pif4pif5 (pifq). Subsequent experiments showed that under various light/dark (L/D) cycle conditions sucrose still markedly induced hypocotyl elongation in Col-0, but exhibited little effects in pifq. Phytohormone gibberellins (GAs) have been proven to be required for sucrose-induced hypocotyl elongation, but application of GA(3) (an active form of GAs) was not able to rescue the impairment observed in pifq, suggesting that impairment of sucrose-induced hypocotyl elongation in pifq is not due to the reduced endogenous GAs. Interestingly, through RT-PCR assay, we found that sucrose up-regulated the transcript level of PIF1, 3, 4, 5 in darkness. Furthermore, this effect was dependent on the presence of GAs. Additionally, under continuous light condition, sucrose markedly inhibited the hypocotyl elongation in Col-0 but not in pifq, whereas exogenous GA(3) could recover the repression in Col-0 but only showed slight effect in pifq. These results collectively indicate that PIFs together with GAs control the effect of sucrose on hypocotyl elongation in Arabidopsis seedlings. (C) 2011 Elsevier GmbH. All rights reserved.