Researchers Identify a Novel Non-Coding RNA Module for Tea Plant Resilience

Tea plant (Camellia sinensis) is an economically important crop with a strong preference for acidic soils, making it vulnerable to salinized and alkalized environments. Soil salinization and alkalization are already major constraints on agricultural productivity, damaging soil health, reducing nutrient availability, and limiting crop growth.

Although long non-coding RNAs have been increasingly recognized as regulators of plant development and stress responses, most tea plant studies have focused on aroma formation and disease resistance. Their roles in salt and alkali tolerance remain poorly understood, creating a need to identify stress-responsive lncRNA regulatory modules in tea plants.

A study (DOI: 10.48130/bpr-0026-0008) published in Beverage Plant Research on 25 June 2026 by Youben Yu's & Lixia Zan's team, Shaanxi University of Technology, reports that lnc87821 represses CsJAZ2, while CsJAZ2 enhances tea plant stress tolerance by activating antioxidant-related responses.

To clarify this regulatory relationship, the researchers used tea plant cultivar 'Shaancha 1' and exposed seedlings to salt stress with 200 mmol·L−1 NaCl and alkali stress with 150 mmol·L⁻¹ NaHCO₃. They cloned CsJAZ2 and lnc87821, analyzed expression patterns by qRT-PCR, and found that CsJAZ2 was induced by both stresses, peaking at about 3.5-fold under salt stress and about 2-fold under alkali stress, while lnc87821 was downregulated.

The two genes showed significant negative correlations under salt and alkali treatments, suggesting a repressive relationship. Subcellular localization experiments showed that CsJAZ2 and lnc87821 were mainly located in the nucleus, supporting their roles in transcriptional regulation. Yeast assays further confirmed that CsJAZ2 has transcriptional activation activity. To test CsJAZ2 function, the team generated Arabidopsis lines overexpressing CsJAZ2 and exposed them to salt and alkali conditions.

These plants showed improved growth under alkali stress, longer roots under stress conditions, and lower accumulation of hydrogen peroxide and superoxide anion, indicating stronger antioxidant capacity. Transcriptome analysis identified 768, 1,640, and 1,051 differentially expressed genes under control, salt, and alkali treatments, respectively, with many related to antioxidant pathways such as POD, GST, MDHAR, and SOD.

The team then used antisense oligonucleotide-mediated silencing in tea shoots. Silencing CsJAZ2 reduced the expression of downstream genes such as CsMYC2, CsERF1, and CsEIL1 and increased hydrogen peroxide accumulation under stress, confirming its protective role. In contrast, silencing lnc87821 increased CsJAZ2 and downstream gene expression, demonstrating that lnc87821 negatively regulates the CsJAZ2 pathway. Coding potential prediction and GUS reporter assays confirmed that lnc87821 functions as a non-coding RNA. Promoter analysis suggested that lnc87821 may affect CsJAZ2 transcription by interfering with ABRE and G-box cis-elements, which are associated with bZIP and bHLH transcription factors.

Overall, the study reveals a new lnc87821-CsJAZ2 regulatory module that helps explain how tea plants respond to salt and alkali stress. By showing that CsJAZ2 strengthens antioxidant defense and that lnc87821 acts as its negative regulator, the research expands current knowledge of non-coding RNA function in tea plants. These findings provide candidate molecular targets for improving tea plant resilience and offer a foundation for future studies on stress-resistant tea breeding.