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Published on: June 25, 2015
A PAMP-Inducible Caffeic Acid O-Methyltransferase Gene (EcCOMT49) From Finger Millet Attenuates Bax-Triggered Cell
Vikash Kumar1,2, Kota Chakarpani1, Mohini Yadav2
1BRIC-National Agri-Food and Biomanufacturing Institute, Sahibzada Ajit Singh Nagar, Punjab, India.
Physiologia Plantarum
|June 25, 2026
Summary
Finger millet
Area of Science:
- Plant biology
- Molecular biology
- Biochemistry
Background:
- Caffeic acid O-methyltransferases (COMTs) are involved in plant metabolism and reactive oxygen species (ROS) regulation during stress.
- Finger millet (Eleusine coracana) possesses various COMT isoforms, but their roles in plant immunity are not well understood.
Purpose of the Study:
- To investigate the function of the PAMP-responsive gene EcCOMT49 in finger millet's defense mechanisms and ROS balance.
- To understand EcCOMT49's role in plant immunity and stress tolerance.
Main Methods:
- Promoter-GUS reporter assays were used to analyze EcCOMT49's transcriptional activity in response to PAMPs (flg22 and chitin).
- Transient expression in Nicotiana benthamiana was performed to assess EcCOMT49's effect on programmed cell death (PCD) and ROS accumulation.
- Tolerance to Sclerotinia sclerotiorum infection was evaluated in plants expressing EcCOMT49.
Main Results:
- EcCOMT49 expression is significantly induced by PAMPs (flg22 and chitin), indicating PAMP-inducible transcriptional activity.
- EcCOMT49 suppresses Bax-induced PCD and reduces ROS accumulation in transient assays.
- EcCOMT49 enhances tolerance to Sclerotinia sclerotiorum, decreasing lesion size and ROS levels during infection.
Conclusions:
- EcCOMT49 acts as a key regulator in plant defense, modulating ROS homeostasis and limiting cell death during biotic stress.
- The PAMP-responsive nature of EcCOMT49 suggests its involvement in plant immune responses.
- Further research is needed to fully elucidate the precise regulatory mechanisms of EcCOMT49 in plant defense.
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