著者
Soichiro Nishiyama Noriyuki Onoue Atsushi Kono Akihiko Sato Koichiro Ushijima Hisayo Yamane Ryutaro Tao Keizo Yonemori
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-140, (Released:2018-02-01)
被引用文献数
11

Persimmon (Diospyros kaki) is a tree crop species that originated in East Asia, consists mainly of hexaploid individuals (2n = 6x = 90) with some nonaploid individuals. One of the unique characteristics of persimmon is the continuous accumulation of proanthocyanidins (PAs) in its fruit until the middle of fruit development, resulting in a strong astringent taste even at commercial fruit maturity. Among persimmon cultivars, pollination-constant and non-astringent (PCNA) types cease PA accumulation in early fruit development and become non-astringent at commercial maturity. PCNA is an allelic trait to non-PCNA and is controlled by a single locus called the ASTRINGENCY (AST) locus. Previous segregation analyses indicated that the AST locus shows hexasomic inheritance; a recessive allele, ast, at this locus confers PCNA. Here, we report a shuttle mapping approach to delimit the AST locus region in the hexaploid persimmon genome by using D. lotus, a diploid relative of D. kaki, as a reference. A D. lotus F1 population of 333 individuals and 296 D. kaki siblings segregating for the PCNA trait were used to map the AST region using haplotype-specific markers covering the AST region. This indicated that the AST locus is syntenic to an approximately 915-kb region of the D. lotus genome. In this 915-kb region, we found several candidates for AST that were revealed from the fruit transcriptome of a population segregating for the PCNA trait. These results could provide important clues for the isolation of AST in hexaploid persimmon.
著者
Tsuyoshi Habu Hisayo Yamane Ippei Naito Soichiro Nishiyama Ayumi Nonaka Takashi Kawai Hisashi Yamada Ryutaro Tao
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.MI-119, (Released:2016-02-09)
被引用文献数
8

Japanese persimmon ‘Totsutanenashi’ (TTN) is a spontaneous small fruit mutant derived from ‘Hiratanenashi’ (HTN). To characterize the small fruit phenotype of TTN, we carried out a histological analysis, plant growth regulator treatments, and a transcriptome analysis using Illumina sequencing. The parenchymal cell number in TTN fruit was significantly less than in HTN fruit, and the parenchymal cell size in TTN fruit was also significantly smaller than that in HTN fruit at the later growing stage. However, the fruit size of TTN recovered by cytokinin treatments [50 or 200 ppm N-(2-chloro-4-pyridyl)-N′-phenylurea]. Thus, diminished cytokinin activity in TTN fruits may lead to less cell division in the early growing stage and less cell enlargement in the later growing stage. A large-scale transcriptome analysis was conducted using Illumina sequencing to determine the differences in gene expressions between TTN and HTN fruits. Illumina sequences were processed, resulting in 21,662,190 read pairs from HTN and 23,195,203 read pairs from TTN. After assembly of all sequences from HTN and TTN, 118,985 contigs (referred to as unigenes hereafter) ranging from 201 to 11,954 bases, with an average length of 915 bases, were obtained. Digital expression analyses revealed that the expression levels of 164 unigenes were significantly higher in HTN than in TTN, while the expression levels of 265 unigenes were significantly higher in TTN. A parametric analysis of gene set enrichment using the expression levels of unigenes showed that the biological process Gene Ontology categories of “cell cycle” and “regulation of cell cycle” were significantly down-regulated in TTN. The cell cycle-related differentially expressed genes included D3-type cyclin and Mitogen-Activated Protein Kinase Kinase Kinase. Based on the obtained results, the possible involvement of cell cycle-related genes in regulating the small fruit phenotype in TTN is discussed.