Department of Molecular Plant Biology, University of California, Berkeley, California 90720.
Plant Physiol. 1986 May;81(1):30-5. doi: 10.1104/pp.81.1.30.
In vitro culture of pericarp segments from fruit of Citrus sinensis (L.) Osbeck cv Valencia was used to determine the temporal sequence in development of chloroplasts from chromoplasts during regreening of the epicarp. Regreening of chromoplasts closely resembled greening of etioplasts, except that regreening proceeded much more slowly. Chlorophyll, the light-harvesting chlorophyll a/b binding protein of photosystem II, the chlorophyll a binding protein of reaction center P-700 of photosystem I, thylakoid membranes, and adenosine triphosphate synthetase were all detected at very low levels in degreened epicarp. All of these increased in parallel during regreening of the epicarp. Ribulose 1,5-bisphosphate carboxylase (RuBPCase) levels were high in degreened epicarp and declined for the first 10 days of culture before reaccumulating in the regreening segments. Light was necessary for the accumulation of all of the chloroplastic components. A lack of exogenous nitrogen did not prevent the accumulation of any chloroplastic component except Ru-BPCase, although accumulation of the other components was reduced. Sucrose at 150 millimolar in media lacking nitrogen markedly inhibited the accumulation of chlorophyll and light-harvesting chlorophyll a/b-protein.
采用柑橘果皮段的离体培养来确定在橘红色果皮脱绿过程中质体叶绿体从有色体中的发育的时间顺序。有色体的复绿与黄化质体的绿化非常相似，只是复绿的速度要慢得多。叶绿素、光系统 II 的捕光叶绿素 a/b 结合蛋白、光系统 I 的反应中心 P-700 的叶绿素 a 结合蛋白、类囊体膜和三磷酸腺苷合酶在脱绿果皮中均以非常低的水平检测到。在果皮复绿过程中，所有这些物质都平行增加。在脱绿果皮中，1,5-二磷酸核酮糖羧化酶（RuBPCase）的水平较高，在培养的前 10 天下降，然后在重新积累的复绿果皮中再次积累。所有叶绿体成分的积累都需要光照。缺乏外源氮不会阻止除 RuBPCase 之外的任何叶绿体成分的积累，尽管其他成分的积累减少了。在缺乏氮的培养基中，150 毫摩尔的蔗糖显著抑制了叶绿素和捕光叶绿素 a/b 蛋白的积累。
