Studies on the regulating mechanism of CAM photosynthesis under high night temperature
Project/Area Number |
08456014
|
Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
作物学
|
Research Institution | Saga University |
Principal Investigator |
NOSE Akihiro Saga University Faculty of Aguriculture, Professor, 農学部, 教授 (80045137)
|
Project Period (FY) |
1996 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥4,400,000 (Direct Cost: ¥4,400,000)
Fiscal Year 1998: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1997: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1996: ¥2,600,000 (Direct Cost: ¥2,600,000)
|
Keywords | CAM / phosphofructokinase / night temperature / isoform / glucose 6-phosphate / Kalanchoe Pinnata / Ananas comosus / Kalanchoe daigremontiana / ゲルクロマトグラフィー / カイソザイム / CAM型光合成 / 高夜温 / 温度 / セイロンベンケイソウ / 解糖系 / pH反応 / 細胞内部位 |
Research Abstract |
When a night temperature higher than 36゚C was maintained, Kalanchoe daigremontiana and K.pinnata shifted from the CAM photosynthesis to C3 photosynthesis, but Ananas comosus did not alter its photosynthesis. In this study, the shifting mechanism from CAM to C3 was investigated on the aspect of glycolysis regulation. ATP-dependent phosphofructokinase (PFK) of the two Kalanchoe species exhibited an optimum temperature of the activity at 35'C, but PPi-dependent PFK of A.comosus increased the activity up to 40゚C.PPi-PFK of A.comosus exhibited two optimum peaks of pH7.2 and 7.6, and ATP-PFK of the Kalankoe species showed an optimum pH of 7.6. Isoelectric point of A.comosus PPi-PFK was changed from two type of pH4.88 and 5.34 in day-form to one type of pH4.80 in night-form. PPi-PFK of A.comosus was eluted as two peaks on DEAB-cellulose column chromatography in both day and night. Each PPi-PFK protein showed ca. 14 mm. and ca. 12 mm. of elution time on size-exclusion chromatography. However, the PPi-PFK protein with large charge density on ion-chromatography was separated to the two proteins. Under high night temperature condition, the increase of glucose 6-phosphate content, which was known as an activator of PEPcase, was depressed in Kalanchoe. As shown above, it was suggested that the glycolysis played an important role in the regulation of CAM photosynthesis.
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Report
(4 results)
Research Products
(14 results)