Cell differentiation and morphogenesis are crucial for the establishment of diverse cell types and organs in multicellular organisms. Trichome cells offer an excellent paradigm for dissecting the regulatory mechanisms of plant cell differentiation and morphogenesis due to their unique growth characteristics. Here, we report the isolation of an Arabidopsis mutant,
Early root growth is critical for plant establishment and survival. We have identified a molecular pathway required for helical root tip movement known as circumnutation. Here, we report a multiscale investigation of the regulation and function of this phenomenon. We identify key cell signaling events comprising interaction of the ethylene, cytokinin, and auxin hormone signaling pathways. We identify the gene
- NSF-PAR ID:
- 10214350
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 118
- Issue:
- 8
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- Article No. e2018940118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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SUMMARY (a berrantlyb ranchedt richome 3–1abt3‐1 ), with a reduced trichome branching phenotype. Positional cloning and molecular complementation experiments confirmed thatabt3‐1 is a new mutant allele ofAuxin resistant 1 (AXR1 ), which encodes the N‐terminal half of ubiquitin‐activating enzyme E1 and functions in auxin signaling pathway. Meanwhile, we found that transgenic plants expressing constitutively active version ofROP2 (CA‐ROP2 ) caused a reduction of trichome branches, resembling that ofabt3‐1 . ROP2 is a member of Rho GTPase of plants (ROP) family, serving as versatile signaling switches involved in a range of cellular and developmental processes. Our genetic and biochemical analyses showedAXR1 genetically interacted withROP2 and mediated ROP2 protein stability. The loss ofAXR1 aggravated the trichome defects ofCA‐ROP2 and induced the accumulation of steady‐state ROP2. Consistently, elevatedAXR1 expression levels suppressedROP2 expression and partially rescued trichome branching defects inCA‐ROP2 plants. Together, our results presented a new mutant allele ofAXR1 , uncovered the effects ofAXR1 andROP2 during trichome development, and revealed a pathway ofROP2 ‐mediated regulation of plant cell morphogenesis in Arabidopsis. -
Abstract Auxin is a hormone that is required for hypocotyl elongation during seedling development. In response to auxin, rapid changes in transcript and protein abundance occur in hypocotyls, and some auxin responsive gene expression is linked to hypocotyl growth. To functionally validate proteomic studies, a reverse genetics screen was performed on mutants in auxin‐regulated proteins to identify novel regulators of plant growth. This uncovered a long hypocotyl mutant, which we called
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Protein-based molecular switches play critical roles in biological processes. The importance of the prolyl
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Abstract In plants,
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