LIGHT-DEPENDENT CHLOROPLAST DEVELOPMENT AND EXPRESSION OF A LIGHT-HARVESTING CHLOROPHYLL A/B-BINDING PROTEIN GENE IN THE GYMNOSPERM GINKGO-BILOBA
LIGHT-DEPENDENT CHLOROPLAST DEVELOPMENT AND EXPRESSION OF A LIGHT-HARVESTING CHLOROPHYLL A/B-BINDING PROTEIN GENE IN THE GYMNOSPERM GINKGO-BILOBA
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DOI：
10.1104/pp.103.3.727
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发表时间：
1993-11-01
期刊：
影响因子：
7.4
通讯作者：
SILVERTHORNE, J
中科院分区：
文献类型：
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作者：
CHINN, E;SILVERTHORNE, J
与针叶树不同，裸子植物银杏依赖于光来合成叶绿素和叶绿体发育。深色生长的幼苗显示完全黄化，包括没有检测到Chl积累，没有叶片扩张，下胚轴伸长增加。当黑暗生长的幼苗置于白光下时，Chl合成和叶片扩张开始，但与被子植物开始快速光形态形成不同，银杏至少需要1周才能转变为正常的光调节生长模式。一个编码银杏光收集复合物II Chl A /b结合蛋白的cDNA克隆（pLhcb*Gb1）被用作该mRNA家族表达的探针。我们发现，与被子植物相同，但与松树形成鲜明对比的是，Lhcb mRNA以高度依赖光的方式表达。除了在光照下生长的叶片中表达外，该序列也在未成熟种子的绿色组织中表达。Lhcb mRNA在绿化过程中与Chl合成的开始平行出现。通过与被子植物和裸子植物的特征序列比较，确定了pLhcb*Gb1的完整序列，推断出的氨基酸序列为I型。
Unlike conifers, the gymnosperm Ginkgo biloba is dependent on light for chlorophyll (Chl) synthesis and initiation of chloroplast development. Dark-grown seedlings show complete etiolation, including no detectable Chl accumulation, no leaf expansion, and increased hypocotyl elongation. When dark-grown seedlings are placed in white light, Chl synthesis and leaf expansion are initiated, but unlike angiosperms, which initiate rapid photomorphogenesis, Ginkgo takes at least 1 week to change to a normal light-regulated pattern of growth. A cDNA clone (pLhcb*Gb1) encoding a Chl a/b-binding protein of light-harvesting complex II from Ginkgo mRNA has been used as a probe for the expression of this family of mRNAs. We have found that, in common with angiosperms but in marked contrast to pines, Lhcb mRNA is expressed in a highly light-dependent manner. In addition to being expressed in light-grown leaves, this sequence is also expressed in the green tissues of immature seeds. The Lhcb mRNA appears during greening in parallel with the onset of Chl synthesis. The complete sequence of pLhcb*Gb1 has been determined and the deduced amino acid sequence was found to be of type I based on comparison with signature sequences of angiosperm and gymnosperm sequences.