Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, The Czech Academy of Sciences, Rozvojová 263, CZ-16502 Prague 6, Czech Republic.
Biology Department, Trent University, Peterborough, ON K9L 0G2, Canada.
Biomolecules. 2021 Feb 3;11(2):209. doi: 10.3390/biom11020209.
Cytokinins are plant hormones, derivatives of adenine with a side chain at the -position. They are involved in many physiological processes. While the metabolism of -zeatin and isopentenyladenine, which are considered to be highly active cytokinins, has been extensively studied, there are others with less obvious functions, such as -zeatin, dihydrozeatin, and aromatic cytokinins, which have been comparatively neglected. To help explain this duality, we present a novel hypothesis metaphorically comparing various cytokinin forms, enzymes of CK metabolism, and their signalling and transporter functions to the comics superheroes Hulk and Deadpool. Hulk is a powerful but short-lived creation, whilst Deadpool presents a more subtle and enduring force. With this dual framework in mind, this review compares different cytokinin metabolites, and their biosynthesis, translocation, and sensing to illustrate the different mechanisms behind the two CK strategies. This is put together and applied to a plant developmental scale and, beyond plants, to interactions with organisms of other kingdoms, to highlight where future study can benefit the understanding of plant fitness and productivity.
细胞分裂素是植物激素，是腺嘌呤的衍生物，在 - 位带有侧链。它们参与许多生理过程。虽然被认为具有高度活性的细胞分裂素 - 玉米素和异戊烯基腺嘌呤的代谢已经得到了广泛的研究，但还有其他功能不太明显的细胞分裂素，如 - 玉米素、二氢玉米素和芳香族细胞分裂素，它们相对被忽视了。为了帮助解释这种双重性，我们提出了一个新的假设，将各种细胞分裂素形式、细胞分裂素代谢的酶及其信号转导和转运功能比作漫画超级英雄绿巨人（Hulk）和死侍（Deadpool）。绿巨人是一个强大但寿命短暂的创造物，而死侍则呈现出一种更微妙和持久的力量。考虑到这种双重框架，本综述比较了不同的细胞分裂素代谢物及其生物合成、转运和感应，以说明两种 CK 策略背后的不同机制。这被整合并应用于植物发育的规模，并超越了植物，与其他王国的生物相互作用，以突出未来研究可以在哪里受益于对植物适应性和生产力的理解。
