Evidence map›Paper›PMID 25059706›Full record

ArticlePlant physiology2014

Chlorophyll degradation: the tocopherol biosynthesis-related phytol hydrolase in Arabidopsis seeds is still missing.

Wei Zhang, Tianqi Liu, Guodong Ren, Stefan Hörtensteiner, Yongming Zhou, Edgar B Cahoon, Chunyu Zhang

Open access · hybridAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Plant physiology, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers.

0numbers the graph read from it
0cells of the map it votes in
33citing papers in PubMed
3.7field-weighted citation impact, top 6% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

33 citing papers in PubMed, 78 citations in OpenAlex.

  1. Review
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  8. 3 Biotech · 2024
    Article
  9. Genome-wide association identifies a missing hydrolase for tocopherol synthesis in plants.Proceedings of the National Academy of Sciences of the United States of America · 2022
    Article
  10. Article
  11. Vitamin E synthesis and response in plants.Frontiers in plant science · 2022
    Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 4 institutions in 3 countries.

Wei ZhangNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Tianqi LiuNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Guodong RenNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Stefan HörtensteinerNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Yongming ZhouNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Edgar B CahoonNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.).
Chunyu ZhangNational Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China (W.Z., T.L., Y.Z., C.Z.);State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China (G.R.);Institute of Plant Biology, University of Zurich, CH-8008 Zurich, Switzerland (S.H.); andCenter for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588 (E.B.C.) zhchy@mail.hzau.edu.cn.
Huazhong Agricultural University · CNFudan University · CNUniversity of Nebraska–Lincoln · USUniversity of Zurich · CH

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Phytyl diphosphate (PDP) is the prenyl precursor for tocopherol biosynthesis. Based on recent genetic evidence, PDP is supplied to the tocopherol biosynthetic pathway primarily by chlorophyll degradation and sequential phytol phosphorylation. Three enzymes of Arabidopsis (Arabidopsis thaliana) are known to be capable of removing the phytol chain from chlorophyll in vitro: chlorophyllase1 (CLH1), CLH2, and pheophytin pheophorbide hydrolase (PPH), which specifically hydrolyzes pheophytin. While PPH, but not chlorophyllases, is required for in vivo chlorophyll breakdown during Arabidopsis leaf senescence, little is known about the involvement of these phytol-releasing enzymes in tocopherol biosynthesis. To explore the origin of PDP for tocopherol synthesis, seed tocopherol concentrations were determined in Arabidopsis lines engineered for seed-specific overexpression of PPH and in single and multiple mutants in the three genes encoding known dephytylating enzymes. Except for modestly increasing tocopherol content observed in the PPH overexpressor, none of the remaining lines exhibited significantly reduced tocopherol concentrations, suggesting that the known chlorophyll-derived phytol-releasing enzymes do not play major roles in tocopherol biosynthesis. Tocopherol content of seeds from double mutants in NONYELLOWING1 (NYE1) and NYE2, regulators of chlorophyll degradation, had modest reduction compared with wild-type seeds, although mature seeds of the double mutant retained significantly higher chlorophyll levels. These findings suggest that NYEs may play limited roles in regulating an unknown tocopherol biosynthesis-related phytol hydrolase. Meanwhile, seeds of wild-type over-expressing NYE1 had lower tocopherol levels, suggesting that phytol derived from NYE1-dependent chlorophyll degradation probably doesn't enter tocopherol biosynthesis. Potential routes of chlorophyll degradation are discussed in relation to tocopherol biosynthesis.

Indexed as

ArabidopsisCarboxylic Ester HydrolasesChlorophyllHydrolasesMutagenesis, InsertionalPhytolSeedsTocopherolsCarboxylic Ester HydrolasesChlorophyllchlorophyllaseHydrolasesPhytolTocopherols

Identifiers

PMID25059706
PMCPMC4149732
OpenAlexW2119892127

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

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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.