Abstract：
Light serves as a pivotal environmental cue regulating various aspects of plant growth and development, including seed germination, seedling de-etiolation, and shade avoidance. Within this regulatory framework, the basic helix-loop-helix transcription factors known as PHYTOCHROME INTERACTING FACTORS (PIFs) play an essential role in orchestrating responses to light stimuli. Phytochromes, acting as red/far-red light receptors, initiate a cascade leading to the degradation of PIFs (except PIF7), thereby triggering transcriptional reprogramming to facilitate photomorphogenesis. Recent research has unveiled multiple post-translational modifications that regulate the abundance and/or activity of PIFs, including phosphorylation, dephosphorylation, ubiquitination, deubiquitination and SUMOylation. Moreover, intriguing findings indicate that PIFs can influence chromatin modifications. These include modulation of Histone 3 Lysine-9 acetylation (H3K9ac), as well as occupancy of histone variants such as H2A.Z (associated with gene repression) and H3.3 (associated with gene activation), thereby intricately regulating downstream gene expression in response to environmental cues. This review summarizes recent advances in understanding PIFs\' role in regulating various signaling pathways with a major focus on photomorphogenesis.
摘要：
光作为调节植物生长和发育各个方面的关键环境线索，包括种子萌发,幼苗去黄化，避免阴凉。在这个监管框架内，称为植物色素相互作用因子(PIFs)的基本螺旋-环-螺旋转录因子在协调对光刺激的反应中起重要作用。植物色素,充当红色/远红光受体，启动导致PIF降解的级联(PIF7除外)，从而触发转录重编程以促进光形态发生。最近的研究揭示了多种调节PIF丰度和/或活性的翻译后修饰，包括磷酸化，去磷酸化,泛素化，去泛素化和磺酰化。此外，有趣的发现表明，PIF可以影响染色质修饰。这些包括组蛋白3赖氨酸-9乙酰化（H3K9ac）的调节，以及H2A等组蛋白变体的占用。Z（与基因抑制相关）和H3.3（与基因激活相关），从而复杂地调节下游基因表达以响应环境线索。这篇综述总结了在理解PIF在调节各种信号通路中的作用方面的最新进展，主要关注光形态发生。
