Tracheary Element Differentiation

Abstract

Tracheary elements (TEs) are cells in the xylem that are highly specialized for transporting water and solutes up the plant. TEs undergo a very well-defined process of differentiation that involves specification, enlargement, patterned cell wall deposition, programmed cell death and cell wall removal. This process is coordinated such that adjacent TEs are joined together to form a continuous network. Expression studies on model systems as diverse as trees and cell cultures have contributed to providing a flood of candidate genes with potential roles in TE differentiation. Analysis of some of these genes has yielded important information on processes such as patterned secondary cell wall deposition. The current challenge is to continue this functional analysis and to use these data and build an integrated model of TE development.

Patterning of plant cell wall deposition by cortical microtubules

“…Like in primary (expanding) cell walls, cortical microtubules recruit cellulose synthase complexes to the plasma membrane 39,40,52 that synthesize the cellulose microfibrils which are incorporated in the existing cell wall matrix 42 . Cortical microtubule arrays in developing xylem cells resemble the secondary cell wall patterns 52,78 . Therefore, the cortical microtubule array is involved in directing the patterned secondary cell wall deposition during xylem formation (chapter 2).…”

“…initial vessel elements differentiating in elongating young plant tissues, consist of periodically spaced bands and spirals enabling cells to stretch with the surrounding tissue as plant tissues elongates, even after programmed cell death. During protoxylem differentiation cortical microtubule arrays are located in similar patterns as the secondary cell wall patterns typical for the protoxylem 78 (chapter 2). In metaxylem, i.e.…”

“…4.2B; chapter 2 & 3). The banded microtubule array underlies periodic cell wall thickenings 78 and when the microtubule dynamics are changed by drugs during xylem differentiation, the patterned deposition of these cell wall thickenings is affected (chapter 2 & 3). Therefore, the microtubule array is considered to act as a template for patterned deposition of cell wall thickenings.…”

Formation of plant tracheary elements in vitro – a review

“…It is a cost-effective and renewable resource for industry and energy demands. The understanding of the underlying processes of wood formation (xylogenesis) is imperative for improving the quantity and quality of wood produced considering the important roles of wood currently and in the future (Bollhöner et al 2012;Oda and Fukuda 2012;Fukuda 2010;Turner et al 2007). …”

Cultura de células em suspensão como ferramenta para estudos em parede celular secundária em gramí­neas C4

“…Assim, diversos estudos tem demonstrado que hormônios vegetais são fatores importantes na regulação da transdiferenciação de elementos traqueais, em espécies vegetais distintas (Fukuda, 1997;Yamamoto et al, 1997;Ogita et al, 2012). O papel da auxina na diferenciação vascular durante o desenvolvimento normal da planta já foi muito bem documentada (Turner et al, 2007). Em bambu, Ogita e colaboradores (2012) Posteriormente esse tempo foi reduzido para 15 dias a fim de minimizar o processo de oxidação das culturas.…”