Control of Leaf and Vein Development by Auxin

Abstract

Leaves are the main photosynthetic organs of vascular plants and show considerable diversity in their geometries, ranging from simple spoonlike forms to complex shapes with individual leaflets, as in compound leaves. Leaf vascular tissues, which act as conduits of both nutrients and signaling information, are organized in networks of different architectures that usually mirror the surrounding leaf shape. Understanding the processes that endow leaves and vein networks with ordered and closely aligned shapes has captured the attention of biologists and mathematicians since antiquity. Recent work has suggested that the growth regulator auxin has a key role in both initiation and elaboration of final morphology of both leaves and vascular networks. A key feature of auxin action is the existence of feedback loops through which auxin regulates its own transport. These feedbacks may facilitate the iterative generation of basic modules that underlies morphogenesis of both leaves and vasculature.

Developmentally based scaling of leaf venation architecture explains global ecological patterns

“…We developed a new synthetic model for the development of vein hierarchy from apical, marginal and plate meristems, based on previously published information for vein development in model species Arabidopsis [21][22][23][24][25][26][27][28] ( Fig. 3), which we further confirmed for 27 other dicotyledon species of a wide range of leaf form on the basis of 25 earlier studies (Supplementary Table S2).…”

Indole-3-acetic acid: A widespread physiological code in interactions of fungi with other organisms

“…In addition, IAA plays a major role in leaf morphogenesis and vasculature network development. 49 Furthermore, IAA is involved in plant -pathogen interactions such as pathogenesis and defense mechanisms. 44 The roles of fungalproduced IAA in different plant -fungus interaction systems suggests that fungi may use IAA and related compounds to interact with plants for pathogenesis or symbiotic strategies, leading to plant growth promotion and basal plant defense mechanism modification.…”

Mapping shape quantitative trait loci using a radius-centroid-contour model

“…Genes are thought to have an important role in controlling phenotypic variation in shape (van der Knapp et al, 2002;Tanksley, 2004;Scarpella et al, 2010); according to quantitative genetic analyses in animals, shape may have a heritability of 0.60-0.70 Monteiro et al, 2002;Klingenberg, 2003;Gilchrist and Crisafulli, 2006). With the development of genotyping techniques, genetic mapping that dissects phenotypic variation into individual quantitative trait loci (QTLs) (Lander and Botstein, 1989) has been used to detect specific QTLs for morphological shape in the mouse, Drosophila and tomato, providing many promising results (Weber et al, 1999;Klingenberg et al, , 2004Klingenberg et al, , 2012van der Knapp et al, 2002;Leamy et al, 2008).…”