October 17, 2025 | Plant Physiology and Biochemistry |
The cellular mechanisms underlying postharvest senescence in dragon fruit (Hylocereus undatus) were explored in a study carried out by Henan University of Science and Technology, China, and The University of Queensland, Australia. Fruit senescence is a complex physiological process influenced by oxidative stress and hormonal signaling, yet its regulation at the cellular level remains poorly understood.
Using single-cell RNA sequencing combined with phenotypic and biochemical analyses, the researchers identified three distinct endocarp cell clusters involved in senescence: ScC4, ScC11, and ScC12. Each cluster exhibited specific functions—ScC4 initiated stress responses, ScC11 regulated flavonoid biosynthesis and reactive oxygen species (ROS) scavenging, and ScC12 was linked to hormone signaling pathways involving abscisic acid and ethylene. Pseudotime trajectory analysis revealed the temporal progression of these cellular roles during fruit aging.
Functional validation through virus-induced gene silencing showed that suppression of the key regulatory gene HuGIP2 led to decreased flavonoid content, higher ROS accumulation, increased lipoxygenase activity, and accelerated senescence. These results suggest that flavonoid-mediated ROS regulation and LOX inhibition are critical for maintaining fruit quality after harvest.
Overall, this study provides a detailed single-cell–level view of endocarp differentiation and offers new mechanistic insights into the molecular control of fruit senescence in tropical crops.
