scholarly journals Dynamic Apical-Basal Enrichment of the F-Actin during Cytokinesis in Arabidopsis Cells Embedded in Their Tissues

2021 ◽  
Author(s):  
Alexis Lebecq ◽  
Aurelie Fangain ◽  
Alice Boussaroque ◽  
Marie-Cecile Caillaud
Keyword(s):  
Cell Division ◽  
Tracking System ◽  
Preprophase Band ◽  
Cell Plate ◽  
Tumor Formation ◽  
Actin Dynamics ◽  
Root Cells ◽  
Developmental Defects ◽  
Plant Cell Division ◽  
Dividing Cells

During the life cycle of any multicellular organism, cell division contributes to the proliferation of the cell in the tissues as well as the generation of specialized cells, both necessary to form a functional organism. Therefore, the mechanisms of cell division need to be tightly regulated, as malfunctions in their control can lead to tumor formation or developmental defects. This is particularly true in land plants, where cells cannot relocate and therefore cytokinesis is key for morphogenesis. In the green lineage, cell division is executed in radically different manners than animals, with the appearance of new structures (the preprophase band (PPB), cytokinetic the cell plate and phragmoplast), and the disappearance of ancestral mechanisms (cleavage, centrosomes). While F-actin and microtubules closely co-exist to allow the orientation and the progression of the plant cell division, recent studies mainly focused on the involvement of microtubules in this key process. Here, we used our recently developed root tracking system to follow actin dynamics in dividing Arabidopsis meristematic root cells. In this study, we imaged in time and space the fluorescent-tagged F-actin reporter Lifeact together with cell division markers in dividing cells embedded in their tissues. In addition to the F-actin accumulation in the phragmoplasts, we observed and quantified a dynamic apical-basal enrichment of the F-actin during cytokinesis. The role and the possible actors responsible for F-actin dynamics during cytokinesis are discussed.

A role for preprophase bands of microtubules in maturation of new cell walls, and a general proposal on the function of preprophase band sites in cell division in higher plants

1990 ◽  
Vol 97 (3) ◽  
pp. 527-537
Author(s):  
Y. MINEYUKI ◽  
B. E. S. GUNNING
Keyword(s):  
Cell Division ◽  
Hair Cells ◽  
Cell Walls ◽  
Higher Plants ◽  
Preprophase Band ◽  
Cell Plate ◽  
Time Lapse ◽  
Spatial Regulation ◽  
Plant Cell Division ◽  
Drug Treatments

Time-lapse video microscopy of dividing Tradescantia stamen hair cells that are undergoing cytokinesis has revealed that the maturation of the new cell wall is aided by factors at the site where the preprophase band of microtubules forms before mitosis. The wall changes from being fluid and wrinkled before it is inserted into the parental wall at the end of cytokinesis, to being stiff and flat by about 20 min after the time of attachment. This change occurs only if the new wall is inserted at the site formerly occupied by the preprophase band. The cell plate does not flatten when it is caused to insert elsewhere by drug treatments or by centrifugal displacement. If insertion at the correct site is delayed locally by centrifugation against the direction of expansion of the cell plate, then flattening is delayed at the same locality. In combination with a number of points from the literature of plant cell division, some of them very long-standing, our observations lead to a general proposal regarding the nature of the preprophase band site, its mode of action and timing of its operations, and how its role in spatial regulation of histogenesis is achieved.

discordia mutations specifically misorient asymmetric cell divisions during development of the maize leaf epidermis

Development ◽  
1999 ◽  
Vol 126 (20) ◽  
pp. 4623-4633 ◽  
Author(s):  
K. Gallagher ◽  
L.G. Smith
Keyword(s):  
Cell Division ◽  
Preprophase Band ◽  
Cytochalasin D ◽  
Leaf Epidermis ◽  
Asymmetric Cell Divisions ◽  
Maize Leaf ◽  
Cell Divisions ◽  
Cytoskeletal Structure ◽  
Dividing Cells ◽  
Preprophase Bands

In plant cells, cytokinesis depends on a cytoskeletal structure called a phragmoplast, which directs the formation of a new cell wall between daughter nuclei after mitosis. The orientation of cell division depends on guidance of the phragmoplast during cytokinesis to a cortical site marked throughout prophase by another cytoskeletal structure called a preprophase band. Asymmetrically dividing cells become polarized and form asymmetric preprophase bands prior to mitosis; phragmoplasts are subsequently guided to these asymmetric cortical sites to form daughter cells of different shapes and/or sizes. Here we describe two new recessive mutations, discordia1 (dcd1) and discordia2 (dcd2), which disrupt the spatial regulation of cytokinesis during asymmetric cell divisions. Both mutations disrupt four classes of asymmetric cell divisions during the development of the maize leaf epidermis, without affecting the symmetric divisions through which most epidermal cells arise. The effects of dcd mutations on asymmetric cell division can be mimicked by cytochalasin D treatment, and divisions affected by dcd1 are hypersensitive to the effects of cytochalasin D. Analysis of actin and microtubule organization in these mutants showed no effect of either mutation on cell polarity, or on formation and localization of preprophase bands and spindles. In mutant cells, phragmoplasts in asymmetrically dividing cells are structurally normal and are initiated in the correct location, but often fail to move to the position formerly occupied by the preprophase band. We propose that dcd mutations disrupt an actin-dependent process necessary for the guidance of phragmoplasts during cytokinesis in asymmetrically dividing cells.

Relationship between preprophase band organization, F-actin and the division site in Allium

1990 ◽  
Vol 97 (2) ◽  
pp. 283-295
Author(s):  
Y. MINEYUKI ◽  
B. A. PALEVITZ
Keyword(s):  
Higher Plants ◽  
Preprophase Band ◽  
Cell Plate ◽  
Mitotic Apparatus ◽  
Division Plane ◽  
Division Site ◽  
Dividing Cells ◽  
G2 Phase

The preprophase band (PPB) of microtubules (Mts), which appears in the G2 phase of the cell cycle in higher plants but disappears well before the end of karyokinesis, is implicated in the determination of the division plane because its location marks the site at which the phragmoplast/cell plate will fuse with the parental plasmalemma during cytokinesis. The PPB first appears as a rather wide array, which progressively narrows before or during prophase. Actin-containing microfilaments (Mfs) have recently been reported in the PPB, but the role of these elements in PPB organization and/or function remains unclear. The present study employed fluorescence and pharmacological methods in symmetrically and asymmetrically dividing epidermal cells of Allium to probe this problem. Our results show that PPBs in cells treated with 2–200μM cytochalasin D (CD) are still transversely aligned but remain two to three times wider than mature bands in control cells. Treatment for 0.5 h at 20 μM is sufficient to make the PPBs abnormally widel Premitotic nuclear migration in asymmetrically dividing cells is also inhibited by CD, as is the positioning of the mitotic apparatus and the new cell plate. The plate is still transverse, however. Band-like arrays of cortical Mfs become evident in most interphase cells by prophase. The band remains quite wide compared to the final dimensions of the Mt PPB, and clearly encompasses it. Levels of CD as high as 200μM decrease the number of cells with transverse actin bands, although a majority still retain them. Other F-actin arrays are disrupted by the drug. Thus, while CD does not inhibit the formation of an initial, broad, transverse PPB in most cells, it does prevent the narrowing process that defines the precise division site. The role of actin in this effect is discussed.

Microtubule and F-actin dynamics at the division site in living Tradescantia stamen hair cells

1992 ◽  
Vol 103 (4) ◽  
pp. 977-988 ◽  
Author(s):  
A.L. Cleary ◽  
B.E.S. Gunning ◽  
G.O. Wasteneys ◽  
P.K. Hepler
Keyword(s):  
Hair Cells ◽  
Preprophase Band ◽  
Cell Plate ◽  
Laser Scanning Microscopy ◽  
Actin Dynamics ◽  
Cell Cortex ◽  
Living Plant ◽  
Rhodamine Phalloidin ◽  
Division Site ◽  
The Future

We have visualised F-actin and microtubules in living Tradescantia virginiana stamen hair cells by confocal laser scanning microscopy after microinjecting rhodamine-phalloidin or carboxyfluorescein-labelled brain tubulin. We monitored these components of the cytoskeleton as the cells prepared for division at preprophase and progressed through mitosis to cytokinesis. Reorganisation of the interphase cortical cytoskeleton results in preprophase bands of both F-actin and microtubules that coexist in the cell cortex, centred on the site at which the future cell plate will fuse with the parent cell wall. The preprophase band of microtubules is formed from microtubules that polymerise and incorporate tubulin during prophase. The preprophase band of actin may form either by reorganisation of pre-existing filaments or by de novo polymerisation. Both cytoskeletal components disappear from the future division site approximately five minutes prior to the breakdown of the nuclear envelope. Cortical microtubules are undetectable throughout mitosis and cytokinesis, whereas cortical F-actin remains abundant, although it is notably excluded from the division site. The phragmoplast, containing both F-actin and microtubules, expands towards the cortical actin exclusion-zone through a region that has no detectable microtubules or F-actin. The phragmoplast comes to rest in the predefined region of the cortex that is devoid of F-actin. It is proposed that cortical F-actin may act as a “negative” template which could position the phragmoplast and cell plate correctly. This is the first in vivo documentation of F- actin dynamics at the division site in living plant cells.

A role for katanin in plant cell division: Microtubule organization in dividing root cells of fra2 and lue1Arabidopsis thaliana mutants

Cytoskeleton ◽  
2011 ◽  
Vol 68 (7) ◽  
pp. 401-413 ◽  
Author(s):  
Emmanuel Panteris ◽  
Ioannis-Dimosthenis S. Adamakis ◽  
Georgia Voulgari ◽  
Galini Papadopoulou
Keyword(s):  
Cell Division ◽  
Plant Cell ◽  
Microtubule Organization ◽  
Root Cells ◽  
Plant Cell Division

scholarly journals Myosin VIII associates with microtubule ends and together with actin plays a role in guiding plant cell division

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Shu-Zon Wu ◽  
Magdalena Bezanilla
Keyword(s):  
Cell Division ◽  
Motor Activity ◽  
Molecular Mechanism ◽  
Plant Cell ◽  
Actin Filaments ◽  
Plant Cells ◽  
Cell Plate ◽  
Cell Periphery ◽  
Division Site ◽  
Plant Cell Division

Plant cells divide using the phragmoplast, a microtubule-based structure that directs vesicles secretion to the nascent cell plate. The phragmoplast forms at the cell center and expands to reach a specified site at the cell periphery, tens or hundreds of microns distant. The mechanism responsible for guiding the phragmoplast remains largely unknown. Here, using both moss and tobacco, we show that myosin VIII associates with the ends of phragmoplast microtubules and together with actin plays a role in guiding phragmoplast expansion to the cortical division site. Our data lead to a model whereby myosin VIII links phragmoplast microtubules to the cortical division site via actin filaments. Myosin VIII's motor activity along actin provides a molecular mechanism for steering phragmoplast expansion.

Confocal microscopy of the cytoskeleton in living plant cells following microinjection of fluorescent probes

1993 ◽  
Vol 51 ◽  
pp. 130-131
Author(s):  
Ann Cleary
Keyword(s):  
Cell Division ◽  
Fluorescent Probes ◽  
Actin Filaments ◽  
Intracellular Transport ◽  
Cell Structure ◽  
Plant Cells ◽  
Cell Plate ◽  
Cell Cortex ◽  
Living Plant ◽  
Rhodamine Phalloidin

Microinjection of fluorescent probes into living plant cells reveals new aspects of cell structure and function. Microtubules and actin filaments are dynamic components of the cytoskeleton and are involved in cell growth, division and intracellular transport. To date, cytoskeletal probes used in microinjection studies have included rhodamine-phalloidin for labelling actin filaments and fluorescently labelled animal tubulin for incorporation into microtubules. From a recent study of Tradescantia stamen hair cells it appears that actin may have a role in defining the plane of cell division. Unlike microtubules, actin is present in the cell cortex and delimits the division site throughout mitosis. Herein, I shall describe actin, its arrangement and putative role in cell plate placement, in another material, living cells of Tradescantia leaf epidermis.The epidermis is peeled from the abaxial surface of young leaves usually without disruption to cytoplasmic streaming or cell division. The peel is stuck to the base of a well slide using 0.1% polyethylenimine and bathed in a solution of 1% mannitol +/− 1 mM probenecid.

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