Muhammad DurreShahwar, Alameldin Hussien F, Oh Sookyung, Montgomery Beronda L, Warpeha Katherine M
Department of Biological Science, University of Illinois at Chicago, Chicago, IL, United States.
MSU-DOE Plant Research Lab, Plant Biology Laboratories, East Lansing, MI, United States.
Front Plant Sci. 2023 Aug 2;14:1220732. doi: 10.3389/fpls.2023.1220732. eCollection 2023.
The seed-to-seedling transition is impacted by changes in nutrient availability and light profiles, but is still poorly understood. Phenylalanine affects early seedling development; thus, the roles of arogenate dehydratases (ADTs), which catalyze phenylalanine formation, were studied in germination and during the seed-to-seedling transition by exploring the impact of light conditions and specific hormone responses in mutants of . gene expression was assessed in distinct tissues and for light-quality dependence in seedlings for each of the six-member gene family. Mutant seedlings were evaluated relative to wild type for germination, photomorphogenesis (blue, red, far red, white light, and dark conditions), anthocyanin accumulation, and plastid development-related phenotypes. ADT proteins are expressed in a light- and tissue-specific manner in transgenic seedlings. Among the analyzed mutants, , , and exhibit significant defects in germination, hypocotyl elongation, and root development responses during the seed-to-seedling transition. Interestingly, exhibits a light-dependent disruption in plastid development, similar to a mutant. These data indicate interactions between photoreceptors, hormones, and regulation of phenylalanine pools in the process of seedling establishment. ADT5 and ADT6 may play important roles in coordinating hormone and light signals for normal early seedling development.
种子到幼苗的转变受到养分可用性和光照条件变化的影响，但目前仍了解甚少。苯丙氨酸会影响幼苗早期发育；因此，通过研究光照条件和特定激素反应对某基因突变体种子萌发及种子到幼苗转变过程的影响，对催化苯丙氨酸形成的预苯酸脱水酶（ADTs）的作用展开了研究。针对由六个成员组成的ADT基因家族，分别评估了其在不同组织中的基因表达以及幼苗对不同光质的依赖性。相对于野生型，对突变体幼苗的萌发、光形态建成（蓝光、红光、远红光、白光和黑暗条件下）、花青素积累以及与质体发育相关的表型进行了评估。ADT蛋白在转基因幼苗中以光和组织特异性的方式表达。在所分析的突变体中，某几个突变体在种子到幼苗转变过程中的萌发、下胚轴伸长和根系发育反应方面表现出显著缺陷。有趣的是，某一突变体在质体发育中表现出光依赖性破坏，类似于另一种突变体。这些数据表明在幼苗建立过程中，光感受器、激素和苯丙氨酸库的调节之间存在相互作用。ADT5和ADT6可能在协调激素和光信号以实现正常的早期幼苗发育中发挥重要作用。
