ArticlePlant physiology2003
Characterization of tocopherol cyclases from higher plants and cyanobacteria. Evolutionary implications for tocopherol synthesis and function.
Article in Plant physiology, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 90 papers.
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Who cites it
90 citing papers in PubMed, 263 citations in OpenAlex.
- A non-classical biosynthetic route enables tocopherol synthesis in bacteria.Nature metabolism · 2026Article
- A century of vitamin E research: The innovative journey from basic biology to synthetic bio-manufacturing.Journal of integrative plant biology · 2026Review
- Quinol C-methyltransferases from extant species of early cyanobacterial lineages shed light on the emergence of plastoquinone in oxygenic phototrophs.Photosynthesis research · 2025Article
- Genomic Analysis of Carotenoid and Vitamin E Biosynthetic Pathways in the Extremophilic Red AlgaAntioxidants (Basel, Switzerland) · 2025Article
- Interplay of rice vitamin E under osmotic and extreme temperature stresses revealed by a comparative transcriptomic approach.BMC plant biology · 2025Article
- Multi-omics analysis of non-pungent (Physiology and molecular biology of plants : an international journal of functional plant biology · 2025Article
- Overexpression of ZmSPS2 increases α/γ-tocopherol ratio to improve maize nutritional quality.Plant biotechnology journal · 2025Article
- The light and hypoxia induced gene ZmPORB1 determines tocopherol content in the maize kernel.Science China. Life sciences · 2024Article
- Multifaceted neuroprotective approach of Trolox in Alzheimer's disease mouse model: targeting Aβ pathology, neuroinflammation, oxidative stress, and synaptic dysfunction.Frontiers in cellular neuroscience · 2024Article
- Potential role of tocopherol in protecting crop plants against abiotic stresses.Physiology and molecular biology of plants : an international journal of functional plant biology · 2023Review
- Vitamins as regulators of calcium-containing kidney stones - new perspectives on the role of the gut microbiome.Nature reviews. Urology · 2023Review
- The evolution of strictly monofunctional naphthoquinol C-methyltransferases is vital in cyanobacteria and plastids.The Plant cell · 2023Article
- Phytol recycling: essential, yet not limiting for tomato fruit tocopherol accumulation under normal growing conditions.Plant molecular biology · 2023Article
- Tocopherol Accumulation and Temporal Expression Analysis of VTE1 and VTE5 Gene Family in Fruit of Two Contrasting Avocado Genotypes.Plant foods for human nutrition (Dordrecht, Netherlands) · 2022Article
- Assessing the Fatty Acid, Carotenoid, and Tocopherol Compositions of Seeds from Apple Cultivars (Foods (Basel, Switzerland) · 2021Article
- Metabolomics of Photosynthetically Active Tissues in White Grapes: Effects of Light Microclimate and Stress Mitigation Strategies.Metabolites · 2021Article
- Article
- Gene Replacement in Arabidopsis Reveals Manganese Transport as an Ancient Feature of Human, Plant and Cyanobacterial UPF0016 Proteins.Frontiers in plant science · 2021Article
- Genome-wide association analysis of natural variation in seed tocochromanols of barley.The plant genome · 2020Article
- Interaction Between Induced and Natural Variation atG3 (Bethesda, Md.) · 2020Article
30 more citing papers are in PubMed but not listed here.
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Authors and funding
4 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Tocopherols are lipophilic antioxidants synthesized exclusively by photosynthetic organisms and collectively constitute vitamin E, an essential nutrient for both humans and animals. Tocopherol cyclase (TC) catalyzes the conversion of various phytyl quinol pathway intermediates to their corresponding tocopherols through the formation of the chromanol ring. Herein, the molecular and biochemical characterization of TCs from Arabidopsis (VTE1 [VITAMIN E 1]), Zea mays (SXD1 [Sucrose Export Deficient 1]) and Synechocystis sp. PCC6803 (slr1737) are described. Mutations in the VTE1, SXD1, or slr1737 genes resulted in both tocopherol deficiency and the accumulation of 2,3-dimethyl-6-phytyl-1,4-benzoquinone (DMPBQ), a TC substrate. Recombinant SXD1 and VTE1 proteins are able to convert DMPBQ to gamma-tocopherol in vitro. In addition, expression of maize SXD1 in a Synechocystis sp. PCC6803 slr1737 knockout mutant restored tocopherol synthesis, indicating that TC activity is evolutionarily conserved between plants and cyanobacteria. Sequence analysis identified a highly conserved 30-amino acid C-terminal domain in plant TCs that is absent from cyanobacterial orthologs. vte1-2 causes a truncation within this C-terminal domain, and the resulting mutant phenotype suggests that this domain is necessary for TC activity in plants. The defective export of Suc in sxd1 suggests that in addition to presumed antioxidant activities, tocopherols or tocopherol breakdown products also function as signal transduction molecules, or, alternatively, the DMPBQ that accumulates in sxd1 disrupts signaling required for efficient Suc export in maize.
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