Evidence map›Paper›PMID 34662400›Full record

ArticlePlant physiology2022

BETA-AMYLASE9 is a plastidial nonenzymatic regulator of leaf starch degradation.

Laure C David, Sang-Kyu Lee, Eduard Bruderer, Melanie R Abt, Michaela Fischer-Stettler, Marie-Aude Tschopp, Erik M Solhaug, Katarzyna Sanchez, Samuel C Zeeman

Open access · hybridAbstract read
In one paragraph

Article in Plant physiology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers.

0numbers the graph read from it
0cells of the map it votes in
27citing papers in PubMed
2.5field-weighted citation impact, top 11% 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

27 citing papers in PubMed, 41 citations in OpenAlex.

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  19. A Genome-Wide Analysis of thePlants (Basel, Switzerland) · 2024
    Article
  20. Article
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

9 authors at 1 institution in 1 country.

Laure C DavidInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.ORCID 0000-0001-7597-5767
Sang-Kyu LeeInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.
Eduard BrudererInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.
Melanie R AbtInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.ORCID 0000-0002-3347-3969
Michaela Fischer-StettlerInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.ORCID 0000-0002-5725-9051
Marie-Aude TschoppInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.
Erik M SolhaugInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.
Katarzyna SanchezInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.ORCID 0000-0002-0613-6019
Samuel C ZeemanInstitute of Molecular Plant Biology, Department of Biology, ETH Zurich, Zurich CH-8092, Switzerland.ORCID 0000-0002-2791-0915
ETH Zurich · CH

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

β-Amylases (BAMs) are key enzymes of transitory starch degradation in chloroplasts, a process that buffers the availability of photosynthetically fixed carbon over the diel cycle to maintain energy levels and plant growth at night. However, during vascular plant evolution, the BAM gene family diversified, giving rise to isoforms with different compartmentation and biological activities. Here, we characterized BETA-AMYLASE 9 (BAM9) of Arabidopsis (Arabidopsis thaliana). Among the BAMs, BAM9 is most closely related to BAM4 but is more widely conserved in plants. BAM9 and BAM4 share features including their plastidial localization and lack of measurable α-1,4-glucan hydrolyzing capacity. BAM4 is a regulator of starch degradation, and bam4 mutants display a starch-excess phenotype. Although bam9 single mutants resemble the wild-type (WT), genetic experiments reveal that the loss of BAM9 markedly enhances the starch-excess phenotypes of mutants already impaired in starch degradation. Thus, BAM9 also regulates starch breakdown, but in a different way. Interestingly, BAM9 gene expression is responsive to several environmental changes, while that of BAM4 is not. Furthermore, overexpression of BAM9 in the WT reduced leaf starch content, but overexpression in bam4 failed to complement fully that mutant's starch-excess phenotype, suggesting that BAM9 and BAM4 are not redundant. We propose that BAM9 activates starch degradation, helping to manage carbohydrate availability in response to fluctuations in environmental conditions. As such, BAM9 represents an interesting gene target to explore in crop species.

Indexed as

Arabidopsisbeta-AmylaseGene Expression Regulation, PlantGenes, PlantPlant Growth RegulatorsPlant LeavesPlastidsStarchbeta-AmylasePlant Growth RegulatorsStarch

Identifiers

PMID34662400
PMCPMC8774843
OpenAlexW3207049269

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LicenceCC BY
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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.