Paper · 2026 · The Plant Journal

The CsMYB44–CsICE1 module mediates flavonoid and catechin biosynthesis to regulate cold tolerance in tea plants ( Camellia sinensis )

Chenyu Shao; Qian Zhu; Rong Xu; et al.

15
claims
26
verbatim quotes
0
citations
3
research areas
✓
Open access

Abstract

The tea plant is an economically important perennial crop whose yield and quality are severely constrained by cold stress. With the increasing frequency of extreme weather events, elucidating the molecular basis of cold tolerance is therefore essential for safeguarding tea production and its associated economic value. Catechins contribute to cold tolerance in tea plants, but the underlying regulatory mechanisms remain poorly understood. Here, we integrated transcriptomic, metabolomic, and physiological approaches to identify the CsMYB44-CsICE1 module, which regulates cold-induced flavonoid and catechin biosynthesis to enhance cold tolerance. Weighted gene co-expression network analysis (WGCNA) revealed that CsICE1 was strongly positively correlated with catechin accumulation and cold tolerance, whereas CsMYB44 was negatively correlated with these traits. Overexpression of CsICE1 in Arabidopsis improved cold tolerance by elevating flavonoid levels and upregulating antioxidant and cold-responsive genes, including AtSOD, AtPOD, and AtCBF1. Conversely, overexpression or silencing CsICE1 in tea plants significantly affected cold sensitivity. Overexpression of CsMYB44 reduced cold tolerance in Arabidopsis, while its silencing enhanced tolerance in tea plants. Yeast one-hybrid, electrophoretic mobility shift, and dual-luciferase assays demonstrated that CsMYB44 directly binds to the promoters of CsICE1, CsCHS (chalcone synthase), CsFLS (flavonol synthase), and CsANR (anthocyanidin reductase) to repress their expression. In contrast, CsICE1 activates the transcription of CsCHS, CsFLS, and CsANR. RT-qPCR analysis further indicated that short-term cold stress suppresses CsMYB44 expression, thereby releasing CsICE1, which subsequently upregulates CsCHS, CsFLS, and CsANR, promoting flavonoid and catechin accumulation and ultimately mitigating cold-induced damage. Collectively, these findings uncover a novel cold-tolerance mechanism in tea plants.

Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 15

Associationobservedoriginal resultpositivemeasured

Claim · model-written summary

CsICE1 positively correlated with catechin accumulation and cold tolerance.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsICE1e0
Outcome
catechin accumulation and cold tolerancee0
Direction
positively correlatede0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“CsICE1 was strongly positively correlated with catechin accumulation and cold tolerance”

✓ located verbatim in the source · abstract, characters 717–804 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Associationobservedoriginal resultnegativemeasured

Claim · model-written summary

CsMYB44 negatively correlated with catechin accumulation and cold tolerance.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsMYB44e0
Outcome
these traitse0
Direction
negatively correlatede0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“whereas CsMYB44 was negatively correlated with these traits.”

✓ located verbatim in the source · abstract, characters 806–866 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

CsICE1 overexpression improved Arabidopsis cold tolerance.

Taxon
ArabidopsisArabidopsise0
Treatment
Overexpression of CsICE1e0
Gene
CsICE1e0
Outcome
cold tolerancee0
Direction
improvede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Arabidopsis
Arabidopsis · Taxon · picture of the genus (one of its species)Original uploader was Brona at en.wikipedia . User:Roepers at nl.wikipedia · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Overexpression of CsICE1 in Arabidopsis improved cold tolerance by elevating flavonoid levels and upregulating antioxidant and cold-responsive genes”

✓ located verbatim in the source · abstract, characters 867–1015 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

CsICE1 overexpression elevated Arabidopsis flavonoid levels.

Taxon
ArabidopsisArabidopsise0
Treatment
Overexpression of CsICE1e0
Gene
CsICE1e0
Outcome
flavonoid levelse0
Direction
elevatinge0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Arabidopsis
Arabidopsis · Taxon · picture of the genus (one of its species)Original uploader was Brona at en.wikipedia . User:Roepers at nl.wikipedia · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Overexpression of CsICE1 in Arabidopsis improved cold tolerance by elevating flavonoid levels and upregulating antioxidant and cold-responsive genes”

✓ located verbatim in the source · abstract, characters 867–1015 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

CsICE1 overexpression upregulated Arabidopsis antioxidant and cold responsive genes.

Taxon
ArabidopsisArabidopsise0
Treatment
Overexpression of CsICE1e0
Gene
AtSOD, AtPOD, and AtCBF1e0
Outcome
antioxidant and cold-responsive genese0
Direction
upregulatinge0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Arabidopsis
Arabidopsis · Taxon · picture of the genus (one of its species)Original uploader was Brona at en.wikipedia . User:Roepers at nl.wikipedia · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Overexpression of CsICE1 in Arabidopsis improved cold tolerance by elevating flavonoid levels and upregulating antioxidant and cold-responsive genes, including AtSOD, AtPOD, and AtCBF1.”

✓ located verbatim in the source · abstract, characters 867–1052 · show in text ↑
Intervention effectobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Changing CsICE1 expression significantly affected cold sensitivity in tea.

Taxon
Camellia sinensisCamellia sinensist0
Treatment
overexpression or silencing CsICE1e0
Gene
CsICE1e0
Outcome
cold sensitivitye0

Not reportedComparatorDirection

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“overexpression or silencing CsICE1 in tea plants significantly affected cold sensitivity.”

✓ located verbatim in the source · abstract, characters 1065–1154 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

CsMYB44 overexpression reduced Arabidopsis cold tolerance.

Taxon
ArabidopsisArabidopsise0
Treatment
Overexpression of CsMYB44e0
Gene
CsMYB44e0
Outcome
cold tolerancee0
Direction
reducede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Arabidopsis
Arabidopsis · Taxon · picture of the genus (one of its species)Original uploader was Brona at en.wikipedia . User:Roepers at nl.wikipedia · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Overexpression of CsMYB44 reduced cold tolerance in Arabidopsis”

✓ located verbatim in the source · abstract, characters 1155–1218 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Silencing CsMYB44 enhanced tea cold tolerance.

Taxon
Camellia sinensisCamellia sinensist0
Treatment
silencinge0
Outcome
tolerancee0
Direction
enhancede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“its silencing enhanced tolerance in tea plants.”

✓ located verbatim in the source · abstract, characters 1226–1273 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

CsMYB44 directly binds promoters of CsICE1, CsCHS, CsFLS and CsANR.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsMYB44e0
Outcome
binds to the promoters of CsICE1, CsCHS (chalcone synthase), CsFLS (flavonol synthase), and CsANR (anthocyanidin reductase)e0

Not reportedDirection

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“CsMYB44 directly binds to the promoters of CsICE1, CsCHS (chalcone synthase), CsFLS (flavonol synthase), and CsANR (anthocyanidin reductase) to repress their expression.”

✓ located verbatim in the source · abstract, characters 1369–1538 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Mechanismobservedoriginal resultmeasured

Claim · model-written summary

CsMYB44 represses expression of its four target genes.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsMYB44e0
Outcome
their expressione0
Direction
represse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“CsMYB44 directly binds to the promoters of CsICE1, CsCHS (chalcone synthase), CsFLS (flavonol synthase), and CsANR (anthocyanidin reductase) to repress their expression.”

✓ located verbatim in the source · abstract, characters 1369–1538 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Mechanismobservedoriginal resultmeasured

Claim · model-written summary

CsICE1 activates transcription of CsCHS, CsFLS and CsANR.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsICE1e0
Outcome
transcription of CsCHS, CsFLS, and CsANRe0
Direction
activatese0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“CsICE1 activates the transcription of CsCHS, CsFLS, and CsANR.”

✓ located verbatim in the source · abstract, characters 1552–1614 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Short term cold stress suppresses CsMYB44 expression.

Taxon
Camellia sinensisCamellia sinensist0
Treatment
short-term cold stresse0
Gene
CsMYB44e0
Outcome
CsMYB44 expressione0
Direction
suppressese0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“short-term cold stress suppresses CsMYB44 expression”

✓ located verbatim in the source · abstract, characters 1655–1707 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Mechanismobservedoriginal resultmeasured

Claim · model-written summary

Cold induced CsMYB44 suppression releases CsICE1.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsICE1e0
Outcome
releasing CsICE1e0
Qualifier
short-term cold stress suppresses CsMYB44 expressione0

Not reportedDirection

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“short-term cold stress suppresses CsMYB44 expression, thereby releasing CsICE1”

✓ located verbatim in the source · abstract, characters 1655–1733 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Mechanismobservedoriginal resultmeasured

Claim · model-written summary

Released CsICE1 promotes flavonoid and catechin accumulation through target gene upregulation.

Taxon
Camellia sinensisCamellia sinensist0
Gene
CsICE1e0
Outcome
flavonoid and catechin accumulatione0
Direction
promotinge0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“CsICE1, which subsequently upregulates CsCHS, CsFLS, and CsANR, promoting flavonoid and catechin accumulation”

✓ located verbatim in the source · abstract, characters 1727–1836 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑
Mechanismobservedoriginal resultpositivemeasured

Claim · model-written summary

The CsICE1 pathway mitigates cold induced damage.

Taxon
Camellia sinensisCamellia sinensist0
Outcome
cold-induced damagee0
Direction
mitigatinge0
Qualifier
flavonoid and catechin accumulatione0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Camellia sinensis
Camellia sinensis · TaxonAxelBoldt at en.wikipedia · Public domain · Wikimedia Commons ↗

Verbatim

e0

“promoting flavonoid and catechin accumulation and ultimately mitigating cold-induced damage.”

✓ located verbatim in the source · abstract, characters 1791–1883 · show in text ↑
t0

“Camellia sinensis”

✓ located verbatim in the source · title, characters 114–131 · show in text ↑

loss of function · disease · Camellia sinensis (black tea)Positive and negative results

9 papers: 5 positive, 4 negative or no effect

4 papers in the same direction as this paper · 4 in the opposite direction

  1. negative
  2. negative
  3. negative

5 papers more in this group

See all 9 papers →

cold · molecular: expression · Camellia sinensis (black tea)Results agree

10 papers: 10 positive, 0 negative or no effect

9 papers in the same direction as this paper

  1. positive
  2. positive
  3. positive

6 papers more in this group

See all 10 papers →

Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.