Characterization of a gene regulatory network underlying astringency loss in persimmon fruit

• Published in: Planta Vol. 247; no. 3; pp. 733 - 743
• Main Authors: Nishiyama, Soichiro, Onoue, Noriyuki, Kono, Atsushi, Sato, Akihiko, Yonemori, Keizo, Tao, Ryutaro
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Science + Business Media 01.03.2018; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Accumulation; Agriculture; Astringents; Biomedical and Life Sciences; Clustering; Cultivars; Developmental stages; Diospyros - genetics; Diospyros - metabolism; Diospyros kaki; Ecology; Forestry; Fruit - metabolism; Fruits; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Plant; Gene Regulatory Networks - genetics; Genes; Genes, Plant - genetics; Life Sciences; Light effects; ORIGINAL ARTICLE; Plant Sciences; Pollination; Proanthocyanidins; Proanthocyanidins - metabolism; Proliferating cell nuclear antigen; Regulators; Regulatory mechanisms (biology); Sequence Alignment; Sequence Analysis, DNA; Transcription factors; Coexpression network analysis; Abiotic stress; Fruit transcriptome; Proanthocyanidins; Diospyros kaki
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-017-2819-0

Persimmon (Diospyros kaki; 2n = 6x = 90) accumulates a large amount of proanthocyanidins (PAs) in its fruit, resulting in an astringent taste. Persimmon cultivars are classified into four types based on the nature of astringency loss and the amount of PAs at maturity. Pollination constant and non-astringent (PCNA)-type cultivars stop accumulating PAs in the early stages of fruit development and their fruit can be consumed when still firm without the need for artificial deastringency treatments. While the PCNA trait has been shown to be conferred by a recessive allele at a single locus (ASTRINGENCY; AST), the exact genetic determinant remains unidentified. Here, we conducted transcriptome analyses to elucidate the regulatory mechanism underlying this trait using developing fruits of an F 1 population segregating for the PCNA trait. Comparisons of the transcriptomes of PCNA and non-PCNA individuals and hierarchical clustering revealed that genes related to the flavonoid pathway and to abiotic stress responses involving light stimulation were expressed coordinately with PA accumulation. Furthermore, coexpression network analyses suggested that three putative transcription factors were central to the PA regulatory network and that at least DkMYB4 and/or DkMYC1, which have been reported to form a protein complex with each other for PA regulation, may have a central role in the differential expression of PA biosynthetic pathway genes between PCNA and non-PCNA.