Molecular basis of brassinosteroid-promoted growth

BR最明显的作用是促进生长。细胞壁的疏松、水分运输的控制和纤维素生物合成的控制被认为是潜在的生理机制。BR对碳同化和分配、蛋白质合成以及为细胞壁合成提供前体的影响也可能是涉及的机制。然而，尽管已发表了大量的研究，但BR的主要作用模式仍然不清楚，现有的数据也没有揭示生理过程与相对研究得较好的基因组事件之间的因果关系。目前的提案打算通过代谢组、转录组、形态和超微结构分析对BR促进拟南芥叶片生长的基础进行综合分析。对时间进程实验的统计分析，以及对具有不同内源BR水平的植物的比较，将允许建立剂量-反应关系，并将初级和次级BR效应分开。这些实验有可能确定调节植物生长的过程。

The most obvious role of BR is growth promotion. Cell wall loosening, control of water transport, and control of cellulose biosynthesis have been suggested as underlying physiological mechanisms. BR effects on carbon assimilation and allocation, protein synthesis, and provision of precursors for cell wall synthesis may also represent involved mechanisms. However, in spite of a large number of published studies the primary mode of action of BR is still unclear, and the available data do not disclose causal relationships between physiological processes and the relatively well-studied genomic events. The proposal at hand intends an integrated analysis of the bases of BR-promoted growth in Arabidopsis leaves by means of metabolome, transcriptome, morphology, and ultrastructure analyses. Statistical analyses of time course experiments, and comparisons of plants with different endogenous BR levels will allow establishing dose-response relationships and separating primary and secondary BR effects. The experiments have the potential to identify the processes that mediate plant growth.