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

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.