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Abstract Protein ubiquitylation is a post-translational modification (PTM) process that covalently modifies a protein substrate with either mono-ubiquitin moieties or poly-ubiquitin chains often at the lysine residues. In Arabidopsis, bioinformatic predictions have suggested that over 5% of its proteome constitutes the protein ubiquitylation system. Despite advancements in functional genomic studies in plants, only a small fraction of this bioinformatically predicted system has been functionally characterized. To expand our understanding about the regulatory function of protein ubiquitylation to that rivalling several other major systems, such as transcription regulation and epigenetics, I describe the status, issues, and new approaches of protein ubiquitylation studies in plant biology. I summarize the methods utilized in defining the ubiquitylation machinery by bioinformatics, identifying ubiquitylation substrates by proteomics, and characterizing the ubiquitin E3 ligase-substrate pathways by functional genomics. Based on the functional and evolutionary analyses of the F-box gene superfamily, I propose a deleterious duplication model for the large expansion of this family in plant genomes. Given this model, I present new perspectives of future functional genomic studies on the plant ubiquitylation system to focus on core and active groups of ubiquitin E3 ligase genes.
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Looking back to look forward: protein–protein interactions and the evolution of development
Summary The evolutionary modification of development was fundamental in generating extant plant diversity. Similarly, the modification of development is a path forward to engineering the plants of the future, provided we know enough about what to modify. Understanding how extant diversity was generated will reveal productive pathways forward for modifying development. Here, I discuss four examples of developmental pathways that have been remodeled by changes to protein–protein interactions. These are cases where changes to developmental pathways have been paralleled by recent changes, selected for or engineered by humans. Extant plant diversity represents a vast treasure trove of molecular solutions to ecological problems. Mining this treasure trove will allow for the intentional modification of plant development for solving future problems.
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- Award ID(s):
- 1652380
- PAR ID:
- 10452096
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 225
- Issue:
- 3
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1127-1133
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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