A Transcriptome Approach Toward Understanding Fruit Softening in Persimmon

Abstract

Persimmon (Diospyros kaki Thunb.), which is a climacteric fruit, softens in 3–5 weeks after harvest. However, little is known regarding the transcriptional changes that underlie persimmon ripening. In this study, high-throughput de novo RNA sequencing was performed to examine differential expression between freshly harvested (FH) and softened (ST) persimmon fruit peels. Using the Illumina HiSeq platform, we obtained 259,483,704 high quality reads and 94,856 transcripts. After the removal of redundant sequences, a total of 31,258 unigenes were predicted, 1,790 of which were differentially expressed between FH and ST persimmon (1,284 up-regulated and 506 down-regulated in ST compared with FH). The differentially expressed genes (DEGs) were further subjected to KEGG pathway analysis. Several pathways were found to be up-regulated in ST persimmon, including “amino sugar and nucleotide sugar metabolism.” Pathways down-regulated in ST persimmon included “photosynthesis” and “carbon fixation in photosynthetic organisms.” Expression patterns of genes in these pathways were further confirmed using quantitative real-time RT-PCR. Ethylene gas production during persimmon softening was monitored with gas chromatography and found to be correlated with the fruit softening. Transcription involved in ethylene biosynthesis, perception and signaling was up-regulated. On the whole, this study investigated the key genes involved in metabolic pathways of persimmon fruit softening, especially implicated in increased sugar metabolism, decreased photosynthetic capability, and increased ethylene production and other ethylene-related functions. This transcriptome analysis provides baseline information on the identity and modulation of genes involved in softening of persimmon fruits and can underpin the future development of technologies to delay softening in persimmon.

A chromosome‐level genome assembly provides insights into ascorbic acid accumulation and fruit softening in guava (Psidium guajava)

“…The abundance of volatile metabolites in mature and soft guava fruit (Moon et al ., 2018) may depend on the hydrolysis of starch, which protects cell membranes and maintains firmness. Starch degradation was also reported as playing a key role in fruit softening in banana (Musaceae) (Shiga et al ., 2011; Song et al ., 2019) and persimmon (Ebenaceae) (Jung et al ., 2017). The reference genome of guava reported here will facilitate studies on both ripening and softening mechanisms and support efforts to prolong the shelf life of guava fruits.…”

Comparative Transcriptomic Analysis of Two Bottle Gourd Accessions Differing in Fruit Size

“…In this study, the upregulation of several ERFs in Hang fruit denotes that they positively contribute to the big fruit size. Numerous studies identified ERF genes as master regulators of the expression levels of phytohormones, cell wall modification, cell cycle, and other important structural genes involved in fruit development and ripening [65][66][67]. Decoding the networks connecting ERFs and other TFs identified in the present work to their target structural genes will highlight the most important genes to target for efficient fruit size manipulation in bottle gourd [68].…”

Exploring the sound-modulated delay in tomato ripening through expression analysis of coding and non-coding RNAs

“…In addition, fruit ripening is related to ethylene production in climacteric fruits (Alexander and Grierson, 2002; Jung et al , 2017). Although ethylene controls the terminal development of fruits, it also controls various defence responses (Díaz et al ., 2002; Alexander and Grierson, 2002).…”