| Autor: |
Yamagishi, Takahiro, Hishinuma, Tasuku, Kataoka, Hironao |
| Předmět: |
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| Zdroj: |
Journal of Plant Research; Aug2003, Vol. 116 Issue 4, p295-300, 6p, 1 Black and White Photograph, 5 Graphs |
| Abstrakt: |
A mature sporophyte of Bryopsis plumosa (Hudson) C. Agardh forms a huge number of zoospores in its cell continuum. Zoospore formation starts with the division of a single giant nucleus and subsequent repeated mitosis. We found that an elevation of photosynthetic activity triggered the division of a mature giant nucleus. Transfer to shortday conditions was not necessary. Giant nuclei did not divide in darkness or in the presence of 1 μM DCMU. Giant nuclei of as many as 90% of sporophtyes started to divide following the addition of 5 mM NaHCO3 to the growth medium under continuous white light (6-12 W m-2 ). Frequency of nuclear division increased with increased light intensity. By combining those parameters that promoted the division of giant nuclei, we developed the "two-step culture method" which is composed of preliminary and main cultures. This new method guarantees that giant nuclei of more than 90% of all sporophytes synchronously divide between 72 and 96 h after the transfer to the main culture (continuous white light of 12 W m -2 in PES medium supplemented with 5 mM NaHCO3). [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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