Faculty Publications

Vein Pattern Development in Adult Leaves of Arabidopsis thaliana

Document Type

Article

Keywords

Arabidopsis thaliana, AtHB‐8, leaf development, procambium, vein pattern, xylem

Journal/Book/Conference Title

International Journal of Plant Science

Volume

165

Issue

2

Abstract

Vein pattern development in the leaves of higher plants requires that a continuous system with hierarchical vein size classes and regular spacing be formed de novo from ground meristem precursors. In this study, we use a molecular marker of procambium identity, AtHB‐8::GUS, to investigate the procambial stage of vein pattern formation in adult rosette leaves of Arabidopsis thaliana and to compare the elaboration of AtHB‐8‐marked vein pattern with that expressed by xylem differentiation. While the well‐studied juvenile leaves of Arabidopsis have a relatively simple brochidodromous vein pattern with the simultaneous appearance of the looped secondary veins, adult leaves have a complex semicraspedodromous vein pattern, and a majority of the straight secondary veins develop progressively. Late‐formed secondary veins either arise in the basal portions of the leaf or are intercalated between earlier‐formed secondary veins. Smaller “connector” veins become enhanced during development to form the subterminal loops of the semicraspedodromous secondary vein pattern. Higher‐order veins, especially freely ending veinlets, are formed throughout leaf expansion, maintaining a stable vein density. These unique features of adult leaf vein pattern are strongly correlated with the presence of marginal serrations and a protracted period of leaf expansion. In early leaf development, AtHB‐8::GUS expression precedes any of the hallmark anatomical features of procambial cells in presumptive procambial strands, defining a “preprocambial” stage. In contrast, AtHB‐8::GUS expression was not detected during the late formation of higher‐order veins, indicating that functionally redundant mechanisms guide the development of leaf vascular pattern.

Department

Department of Biology

Original Publication Date

12-1-2003

DOI of published version

10.1086/382794

Link to Full Text

Comments?

Share

COinS