The role of karrikin in regulating photo- and thermomorphogenesis

烟衍生的卡瑞金斯最近被证明可以诱导拟南芥萌发并抑制下胚轴伸长。尽管对于karrikin如何在分子水平上调控这些反应的了解相对较少，但很明显，信号通路与光信号传导密切相关。除了karrikin信号突变体kai2和smax1smxl2的幼苗表现出对光的响应性改变外，光信号的中心调节因子HY5也是karrikin依赖性抑制下胚轴伸长所必需的。此外，植物对环境温度升高的反应（热形态发生）与光信号密切相关。升高的温度导致下胚轴延长、下胚轴叶片生长和叶柄伸长，这些反应在pif4突变体中都得到了改善，pif4突变体首次被描述为光信号通路中的角色。此外，HY5也被证明在热形态发生中发挥重要作用，拮抗PIF4的作用。在这里，我们的目标是描述新描述的karrikin信号网络和光信号通路之间的联系，重点关注拟南芥B-box蛋白和HY5的作用。此外，我们将探索这些相互作用最终如何调节植物对高温的反应。

Smoke derived karrikins have recently been shown to induce germination and inhibit hypocotyl elongation in Arabidopsis. Although relatively little is known about how karrikin regulates these responses at the molecular level, it is clear that the signalling pathway is closely connected to light signalling. Besides the fact that seedlings of the karrikin signalling mutants kai2 and smax1smxl2 show altered light responsiveness, also the central regulator of light signalling, HY5, is required for karrikin dependent inhibition of hypocotyl elongation. Also plant’s responses to an elevation in the ambient temperature (thermomorphogenesis) show a close connection to light signalling. Elevated temperatures result in an elongated hypocotyl, hyponastic leaf growth and petiole elongation, responses all ameliorated in the pif4 mutant that was first described for its role in the light signalling pathways. Furthermore, HY5 has also been shown to play important roles in thermomorphogenesis, antagonising the effects of PIF4. Here, we aim to delineate the connections between the newly described karrikin signalling network with light signalling pathways focusing on the role of Arabidopsis B-box proteins and HY5. Furthermore, we will explore how these interactions ultimately might regulate the plants responses to elevated temperatures.