Exogenous gibberellin delays maturation in persimmon fruit through transcriptional activators and repressors.

As the harvest season of most fruit is concentrated, fruit maturation manipulation is essential for the fresh fruit industry to prolong sales time. Gibberellin (GA), an important phytohormone necessary for plant growth and development, has also shown a substantial regulatory effect on fruit maturation; however, its regulatory mechanisms remain inconclusive. In this research, preharvest GA3 treatment effectively delayed fruit maturation in several persimmon (Diospyros kaki) cultivars. Among the proteins encoded by differentially expressed genes, 2 transcriptional activators (NAC TRANSCRIPTION FACTOR DkNAC24 and ETHYLENE RESPONSIVE FACTOR DkERF38) and a repressor (MYB-LIKE TRANSCRIPTION FACTOR DkMYB22) were direct regulators of GERANYLGERANYL DIPHOSPHATE SYNTHASE DkGGPS1, LYSINE HISTIDINE TRANSPORTER DkLHT1, and FRUCTOSE-BISPHOSPHATE ALDOLASE DkFBA1, respectively, resulting in the inhibition of carotenoid synthesis, outward transport of an ethylene precursor, and consumption of fructose and glucose. Thus, the present study not only provides a practical method to prolong the persimmon fruit maturation period in various cultivars but also provides insights into the regulatory mechanisms of GA on multiple aspects of fruit quality formation at the transcriptional regulation level.

Full-length transcriptome profiling for fruit development in Diospyros oleifera using nanopore sequencing.

OBJECTIVES: Diospyros oleifera, one of the most economically important Diospyros species, is an ideal model for studying the fruit development of persimmon. While, the lack of whole-transcriptome has hindered the complex transcriptional regulation mechanisms of sugar and tannin during fruit development. DATA DESCRIPTION: We applied Oxford Nanopore Technologies to six developmental stage of fruit from D. oleifera for use in transcriptome sequencing. As a result of full-length transcriptome sequencing, 55.87 Gb of clean data were generated. After mapping onto the reference genome of D. oleifera, 51,588 full-length collapsing transcripts, including 2,727 new gene loci and 43,223 transcripts, were obtained. Comprehensively annotated, 38,086 of new transcripts were functional annotation, and 972 lncRNAs, 7,159 AS events were predicted. Here, we released the transcriptome database of D. oleifera at different stage of fruit development,which will provide a fundamention of to investigatethe transcript structure, variants and evolution of persimmon.

Integrated Metabolomic-Transcriptomic Analysis Reveals Diverse Resource of Functional Ingredients From Persimmon Leaves of Different Varieties.

Persimmon leaves are used for making persimmon leaf tea or as functional ingredients due to their enrichment in flavonoids, the beneficial mineral contents, and favorable flavors contributed by volatile aroma compounds. The varieties/cultivars had a significant influence on the quality and flavor of persimmon leaf tea. In this study, the integrated metabolomic-transcriptomic analysis was conducted to investigate the potential in flavonoid biosynthesis, mineral absorption, and degradation of aromatic compounds from tender leaves of "Diospyros kaki. Heishi" (HS), "Diospyros kaki Thunb. Nishimurawase" (NM), and "Diospyros kaki Thunb. Taifu" (TF), using rootstock "Diospyros Lotus Linn" (DL) as the control. The metabolomic analysis showed that 382, 391, and 368 metabolites were differentially accumulated in the comparison of DL vs. HS, DL vs. NM, and DL vs. TF, respectively, and 229 common metabolites were obtained by comparative analysis. By RNA sequencing, 182,008 unigenes with 652 bp of mean length were annotated and 2,598, 3,503, and 3,333 differentially expressed genes (DEGs) were detected from the comparison of DL vs. HS, DL vs. NM, and DL vs. TF, respectively. After the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, 6, 6, and 3 DEGs [with | log2(fold change)| ≥ 1 simultaneously in the three comparisons] involved in flavonoid biosynthesis, mineral absorption, and degradation of aromatic compounds, respectively, were selected for quantitative reverse transcription-polymerase chain reaction (qRT-PCR) validation and the consistent trends of the relative expression level of each DEG with RNA sequencing (RNA-seq) data were observed. Based on the transcriptomic analysis and qRT-PCR validation, it was observed that the leaves of HS, NM, and TF had the greatest level of mineral absorption, flavonoid biosynthesis, and degradation of aromatic compounds, respectively. In addition, a positive correlation between the 15 DEGs and their metabolites was observed by the conjoint analysis. Thus, the tender leaves of HS, NM, and TF could be recommended for the production of persimmon leaf tea rich in mineral elements, flavonoid, and aroma compounds, respectively.

Characterization of the complete chloroplast genome sequence of Diospyros kaki cv. Luotiantianshi.

Diospyros kaki cv. Luotiantianshi is a rare germplasm of Diospyros Linn in the world. In this study, we generated the complete chloroplast (cp) genome of D. kaki cv. Luotiantianshi. The complete cp genome was 157,773 bp in length, containing a large single copy region (LSC) of 87,066 bp, a small single copy region (SSC) of 18,529 bp, and two inverted repeat (IR) regions of 26,089 bp. The new sequence has a total of 131 genes, including 86 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Further, phylogenetic analysis showed that the D. kaki cv. Luotiantianshi has a close relationship with Diospyros kaki. This study provides important information for future evolution, genetic and molecular biology studies of Diospyros.

The persimmon (Diospyros oleifera Cheng) genome provides new insights into the inheritance of astringency and ancestral evolution.

Persimmon (Diospyros kaki) is an oriental perennial woody fruit tree whose popular fruit is produced and consumed worldwide. The persimmon fruit is unique because of the hyperaccumulation of proanthocyanidins during fruit development, causing the mature fruit of most cultivars to have an astringent taste. In this study, we obtained a chromosome-scale genome assembly for 'Youshi' (Diospyros oleifera, 2n = 2x = 30), the diploid species of persimmon, by integrating Illumina sequencing, single-molecule real-time sequencing, and high-throughput chromosome conformation capture techniques. The assembled D. oleifera genome consisted of 849.53 Mb, 94.14% (799.71 Mb) of which was assigned to 15 pseudochromosomes, and is the first assembled genome for any member of the Ebenaceae. Comparative genomic analysis revealed that the D. oleifera genome underwent an ancient γ whole-genome duplication event. We studied the potential genetic basis for astringency development (proanthocyanidin biosynthesis) and removal (proanthocyanidin insolublization). Proanthocyanidin biosynthesis genes were mainly distributed on chromosome 1, and the clustering of these genes is responsible for the genetic stability of astringency heredity. Genome-based RNA-seq identified deastringency genes, and promoter analysis showed that most of their promoters contained large numbers of low oxygen-responsive motifs, which is consistent with the efficient industrial application of high CO2 treatment to remove astringency. Using the D. oleifera genome as the reference, SLAF-seq indicated that 'Youshi' is one of the ancestors of the cultivated persimmon (2n = 6x = 90). Our study provides significant insights into the genetic basis of persimmon evolution and the development and removal astringency, and it will facilitate the improvement of the breeding of persimmon fruit.