Trends in Plant Science
SpotlightAdaptive Growth: Shaping Auxin-Mediated Root System Architecture
Section snippets
Auxin-Dependent Root System Patterning
Roots, which evolved during the rise of vascular plants, enable plants to anchor themselves in soil and forage for nutrients and water from their surroundings. During plant evolution, the root evolved into an organ with a complex architecture, expediting plant colonization of the terrestrial environment and transforming the landscape of our planet [1].
RSA, which is defined as the spatial distribution of roots in soil and confers plant fitness in particular environments, largely depends on two
Cytokinin Signaling Antagonizes Auxin-Mediated Root Gravitropism to Shape RSA
Cytokinin turnover in arabidopsis depends on the ATP/ADP-isopentenyltransferase (IPT) genes that activate the biosynthesis of cytokinins, and cytokinin oxidase/dehydrogenase (CKX) genes, which inactive the cytokinin accumulation [8]. Waidmann et al. identified the cytokinin metabolism-related gene CKX2, acting as an LR-specific antigravitropic component in defining the angular growth of LRs and spatial architecture of the root system [6]. In vivo and in vitro experiments confirmed that a SNP
An Exocytosis Pathway Modulates Auxin Transport to Shape RSA
The auxin transporter PIN proteins have a pivotal role in root gravitropism, as evidenced by the fact that application of the auxin transporter inhibitor N-1-naphtylphthalamic acid (NPA) interferes with root gravitropism. By comparing NPA sensitivity among 215 natural arabidopsis accessions and then performing GWA mapping, Ogura et al. identified a specific SNP located in the gene EXOCYST70A3 (EXO70A3), a homolog of yeast and human EXO70, which is involved in an endocytosis pathway that
Concluding Remarks and Future Perspectives
Combining the natural variation of geographically representative arabidopsis accessions and GWA mapping, two recent studies identified two key factors, CKX2 and EXO70A3, that explicitly modulate auxin-dependent root gravitropic growth, resulting in a shift between shallow versus deep RSA and, therefore, allowing the ecological adaptation of plants to hypoxia and drought stresses [6,7]. Additionally, RSA is also linked to other root traits, including nutrient uptake, root anchorage, and
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IAA priming improves the germination and seedling growth in cotton (Gossypium hirsutum L.) via regulating the endogenous phytohormones and enhancing the sucrose metabolism
2020, Industrial Crops and ProductsCitation Excerpt :As a critical phytohormones, auxin acts as a critical coordinator of the plant growth and development (Hagen, 2015; Leyser, 2018). It regulates the architecture of the plant, triggers the seed germination and involves in the response to the stress (Bielach et al., 2017; Figueiredo and Köhler, 2018; Luo et al., 2018; Xiao and Zhang, 2020). In cotton, auxin plays a key role in regulating the specific trait.
Dynamics of biochemical and hormonal reserves degradation in immature seeds of Euterpe edulis Martius (Arecaceae) during in vitro germination
2024, Plant Cell, Tissue and Organ CultureThe nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation
2023, Proceedings of the National Academy of Sciences of the United States of America