Tremendous plant metabolic diversity arises from phylogenetically restricted specialized metabolic pathways. Specialized metabolites are synthesized in dedicated cells or tissues, with pathway genes sometimes colocalizing in biosynthetic gene clusters (BGCs). However, the mechanisms by which spatial expression patterns arise and the role of BGCs in pathway evolution remain underappreciated. In this study, we investigated the mechanisms driving acylsugar evolution in the Solanaceae. Previously thought to be restricted to glandular trichomes, acylsugars were recently found in cultivated tomato roots. We demonstrated that acylsugars in cultivated tomato roots and trichomes have different sugar cores, identified root-enriched paralogs of trichome acylsugar pathway genes, and characterized a key paralog required for root acylsugar biosynthesis,SlASAT1-LIKE(SlASAT1-L), which is nested within a previously reported trichome acylsugar BGC. Last, we provided evidence thatASAT1-Larose through duplication of its paralog,ASAT1, and was trichome-expressed before acquiring root-specific expression in theSolanumgenus. Our results illuminate the genomic context and molecular mechanisms underpinning metabolic diversity in plants.
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RNA-Seq analysis of genes affected by Cyclophilin A/DIAGEOTROPICA (DGT) in tomato root development
Cyclophilin A/DIAGEOTROPICA (DGT) has been linked to auxin-regulated development in tomato and appears to affect multiple developmental pathways. Loss of DGT function results in a pleiotropic phenotype that is strongest in the roots, including shortened roots with no lateral branching. Here, we present an RNA-Seq dataset comparing the gene expression profiles of wildtype (‘Ailsa Craig’) anddgttissues from three spatially separated developmental stages of the tomato root tip, with three replicates for each tissue and genotype. We also identify differentially expressed genes, provide an initial comparison of genes affected in each genotype and tissue, and provide the pipeline used to analyze the data. Further analysis of this dataset can be used to gain insight into the effects of DGT on various root developmental pathways in tomato.
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- Award ID(s):
- 1750698
- PAR ID:
- 10565984
- Publisher / Repository:
- PubMed Central
- Date Published:
- Journal Name:
- F1000Research
- Volume:
- 9
- ISSN:
- 2046-1402
- Page Range / eLocation ID:
- 1175
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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