Evidence map›Paper›PMID 31057485›Full record

ReviewFrontiers in endocrinology2019

Melatonin Synthesis and Function: Evolutionary History in Animals and Plants.

Dake Zhao, Yang Yu, Yong Shen, Qin Liu, Zhiwei Zhao, Ramaswamy Sharma, Russel J Reiter

Open access · goldAbstract readReview
PubMed Full text at PMC Publisher
In one paragraph

Review in Frontiers in endocrinology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 300 papers, 4 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
300citing papers in PubMed, 4 pooled it
31.1field-weighted citation impact, top 1% 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

300 citing papers in PubMed, 4 syntheses or guidelines pooled it, 674 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Pooled it
  5. Trial
  6. Review
  7. Article
  8. Article
  9. Overexpression of SerotoninAntioxidants (Basel, Switzerland) · 2026
    Article
  10. Review
  11. Circadian Behavioral and Bioluminescence Rhythms in theJournal of biological rhythms · 2026
    Article
  12. Article
  13. Review
  14. Review
  15. Review
  16. Review
  17. Article
  18. Article
  19. Review
  20. Review

240 more citing papers are in PubMed but not listed here.

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 2 countries.

Dake ZhaoBiocontrol Engineering Research Center of Plant Disease and Pest, Yunnan University, Kunming, China.
Yang YuState Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan University, Kunming, China.
Yong ShenCollege of Agriculture and Biotechnology, Yunnan Agricultural University, Kunming, China.
Qin LiuSchool of Landscape and Horticulture, Yunnan Vocational and Technical College of Agriculture, Kunming, China.
Zhiwei ZhaoState Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan University, Kunming, China.
Ramaswamy SharmaDepartment of Cell Systems and Anatomy, The University of Texas Health Science Center at San Antonio (UT Health), San Antonio, TX, United States.
Russel J ReiterDepartment of Cell Systems and Anatomy, The University of Texas Health Science Center at San Antonio (UT Health), San Antonio, TX, United States.
Yunnan University · CNThe University of Texas Health Science Center at Houston · USThe University of Texas Health Science Center at San Antonio · USYunnan Agricultural University · CN

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Melatonin is an ancient molecule that can be traced back to the origin of life. Melatonin's initial function was likely that as a free radical scavenger. Melatonin presumably evolved in bacteria; it has been measured in both α-proteobacteria and in photosynthetic cyanobacteria. In early evolution, bacteria were phagocytosed by primitive eukaryotes for their nutrient value. According to the endosymbiotic theory, the ingested bacteria eventually developed a symbiotic association with their host eukaryotes. The ingested α-proteobacteria evolved into mitochondria while cyanobacteria became chloroplasts and both organelles retained their ability to produce melatonin. Since these organelles have persisted to the present day, all species that ever existed or currently exist may have or may continue to synthesize melatonin in their mitochondria (animals and plants) and chloroplasts (plants) where it functions as an antioxidant. Melatonin's other functions, including its multiple receptors, developed later in evolution. In present day animals, via receptor-mediated means, melatonin functions in the regulation of sleep, modulation of circadian rhythms, enhancement of immunity, as a multifunctional oncostatic agent, etc., while retaining its ability to reduce oxidative stress by processes that are, in part, receptor-independent. In plants, melatonin continues to function in reducing oxidative stress as well as in promoting seed germination and growth, improving stress resistance, stimulating the immune system and modulating circadian rhythms; a single melatonin receptor has been identified in land plants where it controls stomatal closure on leaves. The melatonin synthetic pathway varies somewhat between plants and animals. The amino acid, tryptophan, is the necessary precursor of melatonin in all taxa. In animals, tryptophan is initially hydroxylated to 5-hydroxytryptophan which is then decarboxylated with the formation of serotonin. Serotonin is either acetylated to

Indexed as

antioxidantbiological rhythmsbiosynthesis enzymesendosymbiosisevolutionmelatoninregulation of melatonin

Identifiers

PMID31057485
PMCPMC6481276
OpenAlexW2943327026

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.