Plant Biology Division, Samuel Roberts Noble Foundation, Ardmore, OK, USA.
Plant Signal Behav. 2011 Oct;6(10):1537-44. doi: 10.4161/psb.6.10.17326. Epub 2011 Oct 1.
Plant diversity in nature is to a large extent reflected by morphological diversity of their leaves. Both simple and dissected (with multiple blades or leaflets) leaves are initiated from shoot apical meristem (SAM) in a highly ordered fashion. Similarly, development of leaflets from leaf marginal meristem (marginal blastozone) is also highly ordered. How morphological diversity of plant leaves is regulated remains an important topic of studies on plant form evolution. Here, we describe isolation and characterization of loss-of-function mutants of auxin efflux transporter MtPIN10 of a legume species, Medicago truncatula. Mtpin10 mutants exhibit defects in diverse developmental processes including leaf and leaflet development. Cross species genetic complementation demonstrates that MtPIN10 and Arabidopsis PIN1 are functional orthologs. Double mutant analyses reveal complex genetic interactions between MtPIN10 and Medicago SINGLE LEAFLET1 (SGL1), and CUP-SHAPED COTYLEDON2 (MtCUC2), three regulatory genes involved in developmental processes including dissected leaf and flower development.
植物的多样性在很大程度上反映在它们叶子的形态多样性上。无论是简单的叶子还是分裂的叶子（具有多个叶片或小叶），都是从茎尖分生组织（SAM）以高度有序的方式产生的。同样，从叶缘分生组织（边缘分生区）发育出的小叶也是高度有序的。植物叶子的形态多样性是如何被调节的，仍然是植物形态进化研究的一个重要课题。在这里，我们描述了豆科植物蒺藜苜蓿生长素外排转运蛋白 MtPIN10 的功能丧失突变体的分离和鉴定。Mtpin10 突变体在包括叶片和小叶发育在内的各种发育过程中表现出缺陷。种间遗传互补实验表明，MtPIN10 和拟南芥 PIN1 是功能上的同源物。双突变体分析揭示了 MtPIN10 与蒺藜苜蓿单小叶 1 （SGL1）和杯状子叶 2 （MtCUC2）之间复杂的遗传相互作用，这三个调控基因参与包括分裂叶和花发育在内的发育过程。
