ArticlePlant physiology2000
Altering expression of cinnamic acid 4-hydroxylase in transgenic plants provides evidence for a feedback loop at the entry point into the phenylpropanoid pathway.
Article in Plant physiology, 2000. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 68 papers.
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Who cites it
68 citing papers in PubMed, 219 citations in OpenAlex.
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- The effects of clonal integration and earthworms on the growth, active constituent accumulation inFrontiers in plant science · 2025Article
- Evolution of aromatic amino acid metabolism in plants: a key driving force behind plant chemical diversity in aromatic natural products.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2024Review
- Transcriptome analysis reveals biosynthesis and regulation of flavonoid in common bean seeds during grain filling.BMC plant biology · 2024Article
- Isolation and Characterization ofGenes · 2024Article
- Integrated analysis of metabolome and transcriptome reveals key candidate genes involved in flavonoid biosynthesis in Pinellia ternata under heat stress.Journal of plant research · 2023Article
- Influence of Different Precursors on Content of Polyphenols inPlants (Basel, Switzerland) · 2023Article
- Targeted control of supporting pathways in paclitaxel biosynthesis with CRISPR-guided methylation.Frontiers in bioengineering and biotechnology · 2023Article
- A proteomic study of the effect of UV-B on the regulatory mechanism of flavonoids metabolism in pea seedlings.Frontiers in nutrition · 2023Article
- Ocimum sanctum, OscWRKY1, regulates phenylpropanoid pathway genes and promotes resistance to pathogen infection in Arabidopsis.Plant molecular biology · 2022Article
- Necessity of rice resistance to planthoppers for OsEXO70H3 regulating SAMSL excretion and lignin deposition in cell walls.The New phytologist · 2022Article
- Transcriptome-based analysis of key pathways relating to yield formation stage of foxtail millet under different drought stress conditions.Frontiers in plant science · 2022Article
- Key Enzymes Involved in the Synthesis of Hops Phytochemical Compounds: From Structure, Functions to Applications.International journal of molecular sciences · 2021Review
- Two putative parallel pathways for naringenin biosynthesis inRSC advances · 2021Article
- Two UGT84A Family Glycosyltransferases Regulate Phenol, Flavonoid, and Tannin Metabolism inFrontiers in plant science · 2021Article
- Silencing of Oleuropein β-Glucosidase Abolishes the Biosynthetic Capacity of Secoiridoids in Olives.Frontiers in plant science · 2021Article
- Enzyme Complexes of Ptr4CL and PtrHCT Modulate Co-enzyme A Ligation of Hydroxycinnamic Acids for Monolignol Biosynthesis inFrontiers in plant science · 2021Article
- Induced Resistance by Ascorbate Oxidation Involves Potentiating of the Phenylpropanoid Pathway and Improved Rice Tolerance to Parasitic Nematodes.Frontiers in plant science · 2021Article
- Structure and Function of the Cytochrome P450 Monooxygenase Cinnamate 4-hydroxylase fromPlant physiology · 2020Article
8 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Pharmacological evidence implicates trans-cinnamic acid as a feedback modulator of the expression and enzymatic activity of the first enzyme in the phenylpropanoid pathway, L-phenylalanine ammonia-lyase (PAL). To test this hypothesis independently of methods that utilize potentially non-specific inhibitors, we generated transgenic tobacco lines with altered activity levels of the second enzyme of the pathway, cinnamic acid 4-hydroxylase (C4H), by sense or antisense expression of an alfalfa C4H cDNA. PAL activity and levels of phenylpropanoid compounds were reduced in leaves and stems of plants in which C4H activity had been genetically down-regulated. However, C4H activity was not reduced in plants in which PAL activity had been down-regulated by gene silencing. In crosses between a tobacco line over-expressing PAL from a bean PAL transgene and a C4H antisense line, progeny populations harboring both the bean PAL sense and C4H antisense transgenes had significantly lower extractable PAL activity than progeny populations harboring the PAL transgene alone. Our data provide genetic evidence for a feedback loop at the entry point into the phenylpropanoid pathway that had previously been inferred from potentially artifactual pharmacological experiments.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.