Barnwell Samantha, Carlson Keisha D, Balderrama Daniel, Pernikoff Sara, Tanatrah Tahseen, Madlung Andreas
Department of Biology University of Puget Sound Tacoma Washington USA.
Plant Direct. 2025 May 23;9(5):e70079. doi: 10.1002/pld3.70079. eCollection 2025 May.
As photoautotrophs, plants use light not only as a source of energy but also as cues for directing growth and development. Phytochromes comprise a small gene family of plant specific light receptors that absorb mostly in the red/far-red portion of the electromagnetic spectrum. These light receptors are well-studied in the model species yet much less is known about their functions in other species. We have generated CRISPR-induced mutations in () and produced higher order mutants, and characterized some of their physiological functions in tomato (). We report that SlphyE plays a major role in detecting far-red light, repressing germination when light conditions are unfavorable for establishing a new seedling. While SlphyE functions on its own, it also synergistically works with another phytochrome, SlphyB1, which by itself only plays a minor role in germination control. Aside from its role in far-red light detection, SlPhyE is also involved in perceiving red light, leading to the repression of hypocotyl elongation and the promotion of light avoidance growth in the roots. SlPhyF acts synergistically with phyB1 during photomorphogenesis but it is not involved in far-red light detection during germination.
作为光合自养生物，植物不仅将光用作能量来源，还将其作为指导生长和发育的信号。光敏色素构成了一个植物特有的光受体小基因家族，主要吸收电磁光谱的红/远红部分。这些光受体在模式物种中已得到充分研究，但在其他物种中的功能却知之甚少。我们在（）中产生了CRISPR诱导的突变并产生了高阶突变体，并在番茄（）中表征了它们的一些生理功能。我们报告说，SlphyE在检测远红光中起主要作用，当光照条件不利于建立新幼苗时抑制种子萌发。虽然SlphyE单独起作用，但它也与另一种光敏色素SlphyB1协同作用，而SlphyB1本身在萌发控制中只起次要作用。除了在检测远红光中的作用外，SlPhyE还参与感知红光，导致下胚轴伸长受到抑制，并促进根中的避光生长。SlPhyF在光形态建成过程中与phyB1协同作用，但它不参与种子萌发期间的远红光检测。
