Photomorphogenic responses in maize seedling development
Photomorphogenic responses in maize seedling development
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DOI：
10.1104/pp.103.029694
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发表时间：
2003-12-01
期刊：
影响因子：
7.4
通讯作者：
Brutnell, TP
中科院分区：
文献类型：
--
作者：
Markelz, NH;Costich, DE;Brutnell, TP
当玉米幼苗感受到光时，中胚轴伸长的速率降低，诱导根生长，并且叶片展开。在叶组织中，叶肉细胞和维管束鞘细胞的命运是确定的，并且每个的前质体分化成每个细胞类型典型的二型叶绿体。虽然它已推断从最近的研究中，在几个模式植物物种，多个感光系统介导的这一过程中，令人惊讶的是，很少有人知道在玉米的光信号转导。在这里，我们研究了两个光形态建成反应在玉米：抑制中胚轴伸长和C4光合分化。通过广泛的调查白色，红色，远红光，蓝光反应之间的种质资源，包括光敏色素缺乏突变株elm1，我们表明，光响应是一个高度可变的性状在玉米。虽然所有的自交系检查似乎有一个功能光敏色素信号转导途径，几个线显示降低蓝光的敏感性。光反应和亚群之间存在显著相关性，表明光反应可能是人工选择的目标。在标准W22近交系和榆树1的各种光制度下的C4基因表达模式的检查表明，细胞特异性模式的C4基因表达保持在完全分化的组织独立的光质量。据我们所知，这些研究结果代表了第一次全面调查的光响应玉米和玉米育种策略进行了讨论。
As an emerging maize (Zea mays) seedling senses light, there is a decrease in the rate of mesocotyl elongation, an induction of root growth, and an expansion of leaves. In leaf tissues, mesophyll and bundle sheath cell fate is determined, and the proplastids of each differentiate into the dimorphic chloroplasts typical of each cell type. Although it has been inferred from recent studies in several model plant species that multiple photoreceptor systems mediate this process, surprisingly little is known of light signal transduction in maize. Here, we examine two photomorphogenic responses in maize: inhibition of mesocotyl elongation and C4 photosynthetic differentiation. Through an extensive survey of white, red, far-red, and blue light responses among a diverse collection of germplasm, including a phytochrome-deficient mutant elm1, we show that light response is a highly variable trait in maize. Although all inbreds examined appear to have a functional phytochrome signal transduction pathway, several lines showed reduced sensitivity to blue light. A significant correlation was observed between light response and subpopulation, suggesting that light responsiveness may be a target of artificial selection. An examination of C4 gene expression patterns under various light regimes in the standard W22 inbred and elm1 indicate that cell-specific patterns of C4 gene expression are maintained in fully differentiated tissues independent of light quality. To our knowledge, these findings represent the first comprehensive survey of light response in maize and are discussed in relation to maize breeding strategies.