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Abstract Protein‐protein interactions play a crucial role in driving cellular processes and enabling appropriate physiological responses in organisms. The plant hormone ethylene signaling pathway is complex and regulated by the spatiotemporal regulation of its signaling molecules. Constitutive Triple Response 1 (CTR1), a key negative regulator of the pathway, regulates the function of Ethylene‐Insensitive 2 (EIN2), a positive regulator of ethylene signaling, at the endoplasmic reticulum (ER) through phosphorylation. Our recent study revealed that CTR1 can also translocate from the ER to the nucleus in response to ethylene and positively regulate ethylene responses by stabilizing EIN3. To gain further insights into the role of CTR1 in plants, we used TurboID‐based proximity labeling and mass spectrometry to identify the proximal proteomes of CTR1 inNicotiana benthamiana. The identified proximal proteins include known ethylene signaling components, as well as proteins involved in diverse cellular processes such as mitochondrial respiration, mRNA metabolism, and organelle biogenesis. Our study demonstrates the feasibility of proximity labeling using theN. benthamianatransient expression system and identifies the potential interactors of CTR1 in vivo, uncovering the potential roles of CTR1 in a wide range of cellular processes.
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Diverse roles of ethylene in maize growth and development, and its importance in shaping plant architecture
Abstract The gaseous plant hormone ethylene is a key developmental and growth regulator, and a pivotal endogenous response signal to abiotic and biotic interactions, including stress. Much of what is known about ethylene biosynthesis, perception, and signaling comes from decades of research primarily in Arabidopsis thaliana and other eudicot model systems. In contrast, detailed knowledge on the ethylene pathway and response to the hormone is markedly limited in maize (Zea mays L.), a global cereal crop that is a major source of calories for humans and livestock, as well as a key industrial biofeedstock. Recent reports of forward screens and targeted reverse genetics have provided important insight into conserved and unique differences of the ethylene pathway and downstream responses. Natural and edited allelic variation in the promoter regions and coding sequences of ethylene biosynthesis and signaling genes alters maize shoot and root architectures, and plays a crucial role in biomass and grain yields. This review discusses recent advances in ethylene research in maize, with an emphasis on the role of ethylene in regulating growth and development of the shoot and root systems, and ultimately how this crucial hormone impacts plant architecture and grain yield.
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- Award ID(s):
- 2126144
- PAR ID:
- 10589515
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 76
- Issue:
- 7
- ISSN:
- 0022-0957
- Format(s):
- Medium: X Size: p. 1854-1865
- Size(s):
- p. 1854-1865
- Sponsoring Org:
- National Science Foundation
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