Instituto de Bioingeniería, Centro de Investigación Operativa, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Alicante, Spain.
Plant Cell Environ. 2011 Dec;34(12):2200-11. doi: 10.1111/j.1365-3040.2011.02415.x. Epub 2011 Sep 22.
Despite the large number of genes known to affect leaf shape or size, we still have a relatively poor understanding of how leaf morphology is established. For example, little is known about how cell division and cell expansion are controlled and coordinated within a growing leaf to eventually develop into a laminar organ of a definite size. To obtain a global perspective of the cellular basis of variations in leaf morphology at the organ, tissue and cell levels, we studied a collection of 111 non-allelic mutants with abnormally shaped and/or sized leaves, which broadly represent the mutational variations in Arabidopsis thaliana leaf morphology not associated with lethality. We used image-processing techniques on these mutants to quantify morphological parameters running the gamut from the palisade mesophyll and epidermal cells to the venation, whole leaf and rosette levels. We found positive correlations between epidermal cell size and leaf area, which is consistent with long-standing Avery's hypothesis that the epidermis drives leaf growth. In addition, venation parameters were positively correlated with leaf area, suggesting that leaf growth and vein patterning share some genetic controls. Positional cloning of the genes affected by the studied mutations will eventually establish functional links between genotypes, molecular functions, cellular parameters and leaf phenotypes.
尽管有大量已知的基因会影响叶片的形状或大小，但我们对叶片形态是如何建立的仍然知之甚少。例如，对于细胞分裂和细胞扩张是如何在不断生长的叶片内被控制和协调，最终发育成具有一定大小的片状器官，我们知之甚少。为了从器官、组织和细胞水平上获得叶片形态变化的细胞基础的整体视角，我们研究了 111 个非等位突变体的集合，这些突变体的叶片形状异常，或大小异常，它们广泛代表了拟南芥叶片形态的突变变化，而这些变化与致死性无关。我们对这些突变体使用图像处理技术来量化从栅栏状叶肉和表皮细胞到叶脉、整个叶片和莲座丛水平的各种形态参数。我们发现表皮细胞大小与叶片面积之间存在正相关，这与长期存在的 Avery 假说一致，即表皮驱动叶片生长。此外，叶脉参数与叶片面积呈正相关，这表明叶片生长和叶脉模式共享一些遗传控制。受研究突变影响的基因的定位克隆最终将在基因型、分子功能、细胞参数和叶片表型之间建立功能联系。
