著者

Alvin Sanjaya Taiki Kobayashi Ryo Nishijima Harue Shinoyama Yusuke Kazama

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.88, no.3, pp.265-272, 2023-09-25 (Released:2023-09-25)

参考文献数

15

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The popular ornamental flowering plant Dianthus hybrida cv. Telstar Scarlet has been found to exhibit two populations, each with distinct flower morphology: female-like and hermaphroditic. In this work, flower development of D. hybrida was characterized through scanning electron microscopy, light- or stereo- microscopy, from flower meristem formation to the fully matured, open flower. The difference between hermaphrodite and female-like plants was initially marked by the phenomenon of anther shrinking in the latter, which was closely associated with pollen shrinking phenomenon, and soon followed by differential elongation rates of pistils and stamens. Furthermore, the female-like anther, albeit exhibiting delay in pollen development initially, could produce microspores, resembling its hermaphrodite counterparts at some point, before shrinking. However, female-like’s pollen and cell wall size never became as large as the hermaphrodite’s.

著者

Kasumi Hashimoto Yusuke Kazama Hiroyuki Ichida Tomoko Abe Koji Murai

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.86, no.4, pp.297-302, 2021-12-25 (Released:2021-12-24)

参考文献数

14

被引用文献数

3

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A mutant showing extra early-flowering and named extra early-flowering4 (exe4) was induced in a previous study by heavy-ion beam mutagenesis of Triticum monococcum strain KU104-1. The exe4 mutant shows heading about 45 days earlier than wild-type KU104-1 in the field. In the present study, we sought to identify the gene that was mutated in exe4 by performing a modified whole-genome sequencing analysis. This analysis exploited a short-read library preparation that uses a modified adaptor and duplex-specific nuclease (DSN) for the efficient elimination of highly repeated sequence elements within genomes. The whole-genome sequence analysis and PCR analysis using an M2 segregation line indicated that the extra-early flowering phenotype of exe4 is associated with a deletion of a gene for a WD repeat protein, named here WHEAT WD REPEAT 1 (WWDR1). Phylogenetic analysis of amino acid sequences showed that the gene is a homolog of Arabidopsis LIGHT-REGULATED WD1 (LWD1) and LWD2, which are circadian clock regulatory genes.

著者

Ayaka Matsuta Takahiro Mayuzumi Hajime Katano Masanori Hatashita Keiichi Takagi Yoriko Hayashi Tomoko Abe Koji Murai Yusuke Kazama

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.86, no.4, pp.317-322, 2021-12-25 (Released:2021-12-24)

参考文献数

43

被引用文献数

1

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A high-LET heavy-ion beam has a severe effect on survival and effectively induces chromosomal rearrangements. In this study, the effect of high-LET heavy-ion irradiation on mutation induction in the M1 generation was investigated in an inbred line of Torenia fournieri, which is a widely used horticultural plant. Dry seeds of the inbred line ‘Zairai murasaki’ were irradiated with a C-ion beam (LET: 50 keV µm−1) or Ar-ion beams (LETs: 184 keV µm−1 or 290 keV µm−1) at different doses, and then sown on 1/2 MS plates. After determining the survival rates from each irradiation condition, appropriate doses of each beam were roughly determined to produce a survival rate of 90%: 300, 75, and 50 Gy for the C-ion beam with a LET of 50 keV µm−1, Ar-ion beam with a LET of 184 keV µm−1, and Ar-ion beam with a LET of 290 keV µm−1, respectively. In the screening of branches with aberrant flowers, one and two aberrant plants were isolated from 16 and 30 M1 plants after irradiation with LETs of 184 keV µm−1 and 290 keV µm−1, respectively. However, no aberrant plants were identified in M1 plants after irradiation with a LET of 50 keV µm−1. We concluded that high-LET heavy-ion beam irradiation is effective in inducing mutations even in the M1 generation of inbred ornamental plants. This technique could be widely used for breeding ornamental plants that can be propagated vegetatively.

著者

Taiki Kobayashi Masako Takahashi Ryo Nishijima Ryuji Sugiyama Kotaro Ishii Shigeyuki Kawano Yusuke Kazama

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.86, no.4, pp.323-328, 2021-12-25 (Released:2021-12-24)

参考文献数

43

被引用文献数

2

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Cytology requires chromosome specimens, thus, effective preparation methods are needed. Chromosome specimens are frequently prepared from plant root tips. Furthermore, cell cycle synchronization using chemical reagents is applied to obtain a large number of metaphase chromosome specimens. In this study, we focused on the timing of root tip sampling, which is optimal for the preparation of chromosome specimens of the dioecious plant Silene latifolia. The timing was determined from the time seeds were subjected to a germination treatment. Observation of metaphase chromosomes using microscopy revealed that the number of mitotic cells peaked 54 h after the germination treatment. This trend was also observed when the DNA synthesis inhibitor aphidicolin was administered from 24 to 9 h before sampling time points. We used ice-cold treatment for 8, 16, and 32 h as a chromosome condensation method. The 16 h treatment produced suitable chromosome specimens showing satellite ends of chromosomes, whereas the 32 h treatment produced well-condensed chromosome specimens, which were suitable for counting chromosome numbers. Our findings suggest that the timing of root tip sampling is essential for effectively producing plant chromosome specimens.

著者

Taiki Kobayashi Moe Kitoh Dmitry A. Filatov Yusuke Kazama

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.88, no.2, pp.91-94, 2023-06-25 (Released:2023-06-24)

参考文献数

49

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White campion (Silene latifolia, Caryophyllaceae) is a classical model species for studies of sex determination and sex chromosome evolution in dioecious plants. Deletion mapping in this species revealed the presence of two Y-linked sex determining genes—the stamen promoting factor (SPF) gene and a gynoecium suppressing factor (GSF), which inspired the development of the classic ‘two genes’ model for dioecy evolution. We recently identified a Y-linked GSFY gene that encodes a CLAVATA3 homolog and causes gynoecium suppression in S. latifolia via WUSCHEL-CLAVATA feedback loop. Interestingly, the WUSCHEL homolog in S. latifolia (SlWUS1) is also sex-linked and both GSFY and SlWUS1 are located in the oldest part of the sex chromosomes, suggesting that selection to prevent recombination between these genes may have contributed to the origination of sex chromosomes in this species. The WUS-CLV3 pathway is also involved in the sexual differentiation of gynoecium development in kiwifruits and melon, indicating that this pathway plays central role in gynoecium suppression in dioecious and monoecious plants.

著者

Tomonari Hirano Yusuke Kazama Hisato Kunitake Tomoko Abe

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.87, no.1, pp.3-6, 2022-03-25 (Released:2022-03-25)

参考文献数

37

被引用文献数

4

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Heavy-ion beams have been used as an effective mutagen in plants. Various studies have extended our understanding of the mutagenic effects of heavy-ion beam irradiation on the plant genome. Heavy-ion beams can be characterized by the linear energy transfer (LET) value, and the LET-dependent mutagenic effects are observed in plant survival, mutation frequency, and mutation spectrum. When we integrate the results of the mutagenic effects obtained from experiments using different detection methods, we must consider a bias, depending on the experimental system. For example, the plant materials, developmental processes, and heredity of induced mutations must be considered. In this review, we organized the mutagenic effects from the perspective of irradiated plant materials and the heredity of the induced mutations.