Expression and function identification of senescence-associated genes under continuous drought treatment in grapevine
You-Mei Li1, Xuan-Si Tang1, Meng-Hao Sun1
1College of Horticulture and Landscape, Yangzhou University, Yangzhou, China.
Abstract:
Natural leaf senescence is critical for plant fitness. Drought-induced premature leaf senescence affects grape yield and quality. However, reports on the regulatory mechanisms underlying premature leaf senescence under drought stress are limited. In this study, two-year-old potted 'Muscat Hamburg' grape plants were subjected to continuous natural drought treatment until mature leaves exhibited senescence symptoms. Physiological and biochemical indices related to drought stress and senescence were monitored. Transcriptome and transgenic Arabidopsis were used to perform expression analyses and functional identification of drought-induced senescence-associated genes. Twelve days of continuous drought stress was sufficient to cause various physiological disruptions and visible senescence symptoms in mature 'Muscat Hamburg' leaves. These disruptions included malondialdehyde and H2O2 accumulation, and decreased catalase activity and chlorophyll (Chl) levels. Transcriptome analysis revealed that most genes involved in photosynthesis and Chl synthesis were downregulated after 12 d of drought treatment. Three key Chl catabolic genes (SGR, NYC1, and PAO) were significantly upregulated. Overexpression of VvSGR in wild Arabidopsis further confirmed that SGR directly promoted early yellowing of cotyledons and leaves. In addition, drought treatment decreased expression of gibberellic acid signaling repressors (GAI and GAI1) and cytokinin signal components (AHK4, AHK2, RR22, RR9-1, RR9-2, RR6, and RR4) but significantly increased the expression of abscisic acid, jasmonic acid, and salicylic acid signaling components and responsive transcription factors (bZIP40/ABF2, WRKY54/75/70, ANAC019, and MYC2). Moreover, some NAC members (NAC0002, NAC019, and NAC048) may also be drought-induced senescence-associated genes. These results provide extensive information on candidate genes involved in drought-induced senescence in grape leaves.
Supplementary Information:
The online version contains supplementary material available at 10.1007/s12298-024-01465-2.
Related Concept Videos
01:57Adaptations that Reduce Water Loss
02:41Responses to Drought and Flooding
02:04Regulation of Transpiration by Stomata
02:15Replicative Cell Senescence
01:10Transcription
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds...
02:02Responses to Salt Stress