On October 4, 2022, Coconut Research Institute of Chinese Academy of Tropical Agricultural Sciences published a research paper entitled "Genome-wide identification of the DOF gene family involved in fruitlet abscission in Areca catechu L." online in the International Journal of Molecular Sciences (JCR1, IF=6.208). In this study, the members of DOF gene family of arecanut were systematically identified at the genomic level for the first time, and their relationship with the early abscission process of arecanut was proposed.
Arecanut (Areca catechu L.) is an important industrial crops in Hainan Province. Abnormal fruit abscission seriously affects the yield, which is an urgent problem to be solved in Arecanut planting industry. Fruitlet shedding is triggered by a variety of environmental and developmental signals. Our research team previously found that DOF gene family members showed significant changes in their expression levels during fruitlet shedding through transcriptome analysis. DOF (DNA binding with one finger) gene family is a kind of plant-specific transcription factor, which belongs to zinc finger super-family. In this study, a genome-wide analysis of AcDOFs of arecanut was performed to analyze their gene structure, phylogenetic relationships, promoter regions, chromosomal positions and collinearity. At the same time, the changes of cell structure before and after abscission of arecanut were observed, and the transcription levels of AcDOFs gene in the abscission region were compared with that in the abscission region. Six key AcDOFs were identified in the abscission region of A. catechu, and three of them were further identified as key genes related to the process of fruitlet abscission.
Figure 1: Phenotype analysis of betel nut fruit abscission
Transcription Factor (TF)-Centered Yeast One Hybrid technology was further used to screen 33 motifs that the key gene AcDOF4 may recognize and bind. These motifs are found in promoter regions of several genes known to be involved in abscission, including genes encoding cellulose synthase, pectinesterase, polygalacturonase and expansins. Consistent with the prediction, the expression of these genes differed significantly between the “about-to-abscise” and “non-abscised” layers of fruitlet. The results will provide new insights for the DOF pathway functioning in the fruitlet abscission process of A. catechu.
Figure 2: Morphological analysis of areca nut abscisic cells
Figure 3: Collinearity analysis
Dr. Li Jia of Coconut Research Institute of Chinese Academy of Tropical Agricultural Sciences, is the first author of the paper, and Li Meng, associate Professor of Central South University of Forestry and Technology is the corresponding author. This work is supported by grants from the Hainan Province Science and Technology Special Fund, China (ZDYF2022XDNY165).
Link: https://doi.org/10.3390/ijms231911768
