De-Esterified Homogalacturonan Enrichment of the Cell Wall Region Adjoining the Preprophase Cortical Cytoplasmic Zone in Some Protodermal Cell Types of Three Land Plants.

Eleni Giannoutsou,Basil Galatis,Panagiotis Apostolakos

doi:10.3390/ijms21010081

Abstract

The distribution of highly de-esterified homogalacturonans (HGs) in dividing protodermal cells of the monocotyledon Zea mays, the dicotyledon Vigna sinensis, and the fern Asplenium nidus was investigated in order to examine whether the cell wall region adjoining the preprophase band (PPB) is locally diversified. Application of immunofluorescence revealed that de-esterified HGs were accumulated selectively in the cell wall adjacent to the PPB in: (a) symmetrically dividing cells of stomatal rows of Z. mays, (b) the asymmetrically dividing protodermal cells of Z. mays, (c) the symmetrically dividing guard cell mother cells (GMCs) of Z. mays and V. sinensis, and (d) the symmetrically dividing protodermal cells of A. nidus. A common feature of the above cell types is that the cell division plane is defined by extrinsic cues. The presented data suggest that the PPB cortical zone-plasmalemma and the adjacent cell wall region function in a coordinated fashion in the determination/accomplishment of the cell division plane, behaving as a continuum. The de-esterified HGs, among other possible functions, might be involved in the perception and the transduction of the extrinsic cues determining cell division plane in the examined cells.

Highlights

The appearance of the cell wall during plant evolution triggered a wide range of adaptations in the plant cell function, completely deviating from the respective processes of animal cells
The cell divisions that occurred in them are: (a) symmetrical divisions that multiply the protodermal cells (Figure 1a), (b) asymmetrical divisions of the stomatal row cells that produce the guard cell mother cells (GMCs) (Figure 1a,b), (c) asymmetrical divisions of the SMCs, which generate the subsidiary cells of the stomatal complexes (Figure 1c,d), and (d) symmetrical division of the GMCs, which gives rise to the guard cell pair (Figure 1d)
The data presented in this work show that in the (a) symmetrically dividing cells of the protodermal rows of Z. mays, (b) asymmetrically dividing protodermal cells forming the GMCs in Z. mays, (c) SMCs of Z. mays, (d) GMCs of Z. mays and V. sinensis, and (e) symmetrically dividing protodermal cells of A. nidus, the cell wall on the cell division plane becomes locally differentiated by the local accumulation of highly de-esterified HGs in the cell wall adjoining the preprophase band (PPB) cortical zone

Summary

Introduction

The appearance of the cell wall during plant evolution triggered a wide range of adaptations in the plant cell function, completely deviating from the respective processes of animal cells. Land plants have developed a unique interphase mechanism to define their division plane, a process not completely understood so far. This mechanism becomes evident by the organization of the preprophase band (PPB), a polarized cortical cytoplasmic zone, where the future cell plate fuses with the parent cell wall [1,2,3,4]. This is traversed by overlapping closed rings of microtubules (MT-PPB) [5], actin filaments (AF-PPB), [6] and, in some cases, tubular endoplasmic reticulum (ER-PPB) [7,8,9,10]. In the PPB cortical zone a mechanism functions, which either attracts or guides the cell plate at late cytokinesis to be anchored on the parent cell walls at predetermined sites [1,4,11,12,13]

Methods

Results

Conclusion