Kusnetsov V, Herrmann R G, Kulaeva O N, Oelmüller R
K.A. Timiriazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow.
Mol Gen Genet. 1998 Jul;259(1):21-8. doi: 10.1007/pl00008626.
Plastid biogenesis in etiolated lupine (Lupinus luteus L.) cotyledons is highly sensitive to cytokinins and abscisic acid. In the presence of the synthetic cytokinin N6-benzylaminopurine, greening and plastid biogenesis is substantially promoted as compared to untreated controls, whereas abscisic acid has an inhibitory effect. Faster greening in cytokinin-treated cotyledons is accompanied by a higher level and slower degradation of the light-sensitive protochlorophyllide-oxidoreductase (POR); while ABA has the opposite effect. The phytohormones appear to modulate POR gene expression, since the steady-state levels of POR mRNA, as well as transcripts of other nuclear genes for plastid proteins, are strongly increased by cytokinin and reduced by abscisic acid treatment. When etiolated lupine cotyledons were illuminated with far-red light prior to phytohormone application, the POR level substantially decreased; this was accompanied by the loss of the phytohormone's effect on greening. Based on these findings it is concluded that the level of POR and the integrity of the prolamellar body is crucial for cytokinin- and abscisic acid-controlled greening following transfer of etiolated lupine cotyledons into the light.
黄化羽扇豆（Lupinus luteus L.）子叶中的质体生物发生对细胞分裂素和脱落酸高度敏感。与未处理的对照相比，在合成细胞分裂素N6-苄基腺嘌呤存在的情况下，绿化和质体生物发生得到显著促进，而脱落酸则具有抑制作用。细胞分裂素处理的子叶中更快的绿化伴随着光敏感原叶绿素酸酯氧化还原酶（POR）水平的升高和降解速度的减慢；而脱落酸则具有相反的效果。植物激素似乎调节POR基因的表达，因为细胞分裂素强烈增加POR mRNA以及其他质体蛋白核基因转录本的稳态水平，而脱落酸处理则使其降低。当在施加植物激素之前用远红光照射黄化羽扇豆的子叶时，POR水平大幅下降；这伴随着植物激素对绿化作用的丧失。基于这些发现可以得出结论，POR的水平和原片层体的完整性对于黄化羽扇豆的子叶转移到光照后细胞分裂素和脱落酸控制的绿化至关重要。
