Real-time analysis of photoassimilate translocation in intact eggplant fruit using 11CO2 and a positron-emitting tracer Imaging system
Real-time analysis of photoassimilate translocation in intact eggplant fruit using 11CO2 and a positron-emitting tracer Imaging system
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DOI：
10.2503/jjshs1.77.199
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发表时间：
2008-04-01
影响因子：
--
通讯作者：
Kawachi, Naoki
中科院分区：
文献类型：
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作者：
Kikuchi, Kaori;Ishii, Satomi;Kawachi, Naoki
最近开发的正电子发射示踪成像系统(PEIPS)非侵入性地产生各种化合物在植物中运动的实时定量图像。为了阐明茄子(Solanum melongena L.)果实生长发育的机制，我们用(CO2)-C-11喂入茄子的一片叶片，并通过叶柄监测C-11标记的光合作用产物向果实的运转。产生了[C-11]光同化物从叶片到果实和果实内部转移的连续图像，时间分辨率比以前报道的要短。果实中C-11信号强度逐渐增强，且分布不均匀。测量完果肉后将水果切片，并将其暴露在生物成像分析仪系统的成像板上。合成的图像显示了C-11活性在果实内的定位，并表明光合作用同化物在果实内的转移不均匀。通过对PETERS数据的分析，估计了光合作用产物在花序梗中的运转速度和在果实中的光同化产物运转速率的变化。光合作用物质通过花梗的转运速度估计为1.17 cm·min(-1)。开始摄食(CO2)-C-11约60min后，果实的C-11活性开始升高，到120min时已达到摄食(CO2)-C-11的8%左右。这些结果表明，第一批[C-11]光合作用产物到达果实大约需要60min。光合作用在果实内转运的实时观察尚未见报道。花柄可能是揭示果实发育和成熟机制的有力工具。
A recently developed positron-emitting tracer imaging system (PETIS) noninvasively produces quantitative real-time images of the movement of various compounds in plants. To clarify the mechanism of the growth and development of the fruit of eggplant (Solanum melongena L.), we fed (CO2)-C-11 to a leaf and monitored the translocation of C-11-labeled photoassimilate into the fruit by PETIS. Continuous images of the translocation of [C-11]photoassimilate from the leaf to the fruit and inside the fruit were produced, with a shorter time resolution than reported previously. C-11 signal intensity in the fruit increased gradually, and its distribution was not uniform. The fruits were sliced after PETIS measurement and exposed to the imaging plates of a bio-imaging analyzer system. The resultant images showed the localization of C-11 activity inside the fruit, and indicated that translocation of photoassimilate within the fruit was not uniform. The velocity of photoassimilate translocation in the peduncle and changes in the rate of translocation of photoassimilate in the fruit were estimated by analysis of PETIS data. The velocity of photoassimilate translocation through the peduncle was estimated as 1.17 cm.min(-1). About 60 min after the start Of (CO2)-C-11 feeding, the C-11 activity of the fruit began to increase, and by 120 min it had reached about 8% of feeding (CO2)-C-11. These results indicate that it took about 60 min for the first [C-11]photoassimilates to reach the fruit. Real time observation of photoassimilate translocation within a fruit has never been reported. PETIS may be a powerful tool for revealing the mechanisms of fruit development and maturity.