Glycyrrhiza uralensis Nodules: Histological and Ultrastructural Organization and Tubulin Cytoskeleton Dynamics

Chinese liquorice (Glycyrrhiza uralensis Fisch. ex DC.) is widely used in the food industry and as a medicine. Like other legumes, G. uralensis forms symbiotic nodules. However, the structural organization of G. uralensis nodules is poorly understood. In this study, we analyzed the histological and ultrastructural organization and dynamics of the tubulin cytoskeleton in various cells from different histological zones of indeterminate nodules formed by two strains of Mesorhizobium sp. The unusual walls of infection threads and formation of multiple symbiosomes with several swollen bacteroids were observed. A large amount of poly-β-hydroxybutyrate accumulated in the bacteroids, while the vacuoles of meristematic and uninfected cells contained drop-shaped osmiophilic inclusions. Immunolocalization of the tubulin cytoskeleton and quantitative analysis of cytoskeletal elements revealed patterns of cortical microtubules in meristematic, infected and uninfected cells, and of endoplasmic microtubules associated with infection structures, typical of indeterminate nodules. The intermediate pattern of endoplasmic microtubules in infected cells was correlated with disordered arrangement of symbiosomes. Thus, analysis of the structural organization of G. uralensis nodules revealed some ancestral features more characteristic of determinate nodules, demonstrating the evolutionary closeness of G. uralensis nodulation to more ancient members of the legume family.

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Influence of mutation in pea (Pisum sativum L.) cdt (cadmium tolerance) gene on histological and ultrastructural nodule organization

Ecological genetics ◽

10.17816/ecogen17171-80 ◽

2019 ◽

Vol 17 (1) ◽

pp. 71-80 ◽

Cited By ~ 2

Author(s):

Anna V. Tsyganova ◽

Elena V. Seliverstova ◽

Viktor E. Tsyganov

Keyword(s):

Structural Organization ◽

Ultrastructural Organization ◽

Pisum Sativum L ◽

Transmission Electron ◽

Infected Cells ◽

Peribacteroid Space ◽

Tolerance Gene ◽

Tolerance To Cadmium ◽

Initial Line ◽

Partial Destruction

Background. A comparative analysis out of the structural organization of the symbiotic nodules of the pea initial line SGE and the mutant line SGECdt, characterized by increased tolerance to cadmium and increased its accumulation, was carried out. Materials and methods.Nodules of initial line SGE and mutant SGECdt were analyzed using light and transmission electron microscopy. Results. The non-treated nodules of SGE and SGECdt were characterized by a similar histological and ultrastructural organization. In the nodules of SGE exposed to 100 M CdCl2 in infected cells, the following abnormalities were observed: expansion of the peribacteroid space, destruction of the symbiosome membrane, fusion of symbiosomes and, as a result, the formation of symbiosomes containing several bacteroids. In the nodules of SGECdt, infected cells did not undergo pronounced changes. In the nodules of SGE exposed to 1 mM CdCl2, at the base of the nodule, senescent infected cells with completely destroyed cytoplasm and degrading bacteroids appeared. Also there were present cells in which the contents of symbiosomes were lysing, and only the ghosts of the bacteroids remained in them. In SGECdt, in some infected cells, abnormalities were manifested in an increase in the peribacteroid space, partial destruction of symbiosome membranes, fusion of symbiosomes, and release of bacteroids into the vacuole. Conclusions. The tolerance of pea nodules to cadmium can be significantly increased due to a single recessive cdt mutation.

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Root nodule structure in Chamaecytisus podolicus

Acta Agrobotanica ◽

10.5586/aa.1716 ◽

2017 ◽

Vol 70 (2) ◽

Cited By ~ 3

Author(s):

Monika Skawińska ◽

Barbara Łotocka ◽

Tomasz Ruszkowski ◽

Piotr Banaszczak ◽

Ewa Znojek

Keyword(s):

Root Nodule ◽

Root Nodules ◽

Structural Features ◽

Meristematic Cells ◽

Indeterminate Nodules ◽

Infection Threads ◽

Root Nodule Structure ◽

Infected Cells ◽

First Time ◽

Sister Cells

By means of microscopic analyses, it was shown that root nodules formed by Chamaecytisus podolicus exhibited all structural features typical for indeterminate nodules of temperate genistean shrubs: (i) apical nodule meristem composed of infected and non-infected domains, (ii) parenchymatous bacteroid-containing tissue with infected cells only resulting from mitotic activity of infected meristematic cells, (iii) absence of infection threads, and (iv) convoluted bacteroids singly enclosed in a symbiosome membrane. For the first time, it was shown that the nodule meristem is organized into longitudinal files of sister cells.

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Ontogenèse des nodules caulinaires du Sesbania rostrata (légumineuses)

Canadian Journal of Botany ◽

10.1139/b84-137 ◽

1984 ◽

Vol 62 (5) ◽

pp. 982-994 ◽

Cited By ~ 40

Author(s):

E. Duhoux

Keyword(s):

Sesbania Rostrata ◽

Cortical Cells ◽

Root Cortex ◽

Central Mass ◽

Intracellular Release ◽

Infection Threads ◽

Bacterial Penetration ◽

Infected Cells ◽

Determinate Growth

Stem nodules of the legume Sesbania rostrata are ovoids, contain chlorophyll and have determinate growth. They possess a large central mass of infected cells. Stem mamillae are regularly arranged in vertical files along the stem and develop into nodules when they are infected by a specific Rhizobium. Each nodule arises from the development of an infected region of the incipient root cortex. The infection in S. rostrata has been shown to proceed in four sequential stages. Some of them have never been shown to occur in other legumes: (i) bacterial penetration takes place in degenerated (dead) cortical cells; (ii) proliferation of the bacteria occurs in the intercellular cavities and initiates a meristematic nodule; (iii) protusion of infection threads at first occurs intercellularly and then intracellularly from the cavities; (iv) finally there is an intracellular release of Rhizobia by an endocytotic process.

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MicroRNA Regulatory Pathways in the Control of the Actin–Myosin Cytoskeleton

Cells ◽

10.3390/cells9071649 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1649 ◽

Cited By ~ 1

Author(s):

Karen Uray ◽

Evelin Major ◽

Beata Lontay

Keyword(s):

Gene Regulation ◽

Cardiovascular Function ◽

Signaling Cascades ◽

Regulatory Pathways ◽

Physiological Processes ◽

Human Disorders ◽

Huge Impact ◽

Transcriptional Gene Regulation ◽

Cytoskeletal Elements ◽

Cytoskeleton Dynamics

MicroRNAs (miRNAs) are key modulators of post-transcriptional gene regulation in a plethora of processes, including actin–myosin cytoskeleton dynamics. Recent evidence points to the widespread effects of miRNAs on actin–myosin cytoskeleton dynamics, either directly on the expression of actin and myosin genes or indirectly on the diverse signaling cascades modulating cytoskeletal arrangement. Furthermore, studies from various human models indicate that miRNAs contribute to the development of various human disorders. The potentially huge impact of miRNA-based mechanisms on cytoskeletal elements is just starting to be recognized. In this review, we summarize recent knowledge about the importance of microRNA modulation of the actin–myosin cytoskeleton affecting physiological processes, including cardiovascular function, hematopoiesis, podocyte physiology, and osteogenesis.

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Structure and Assembly of Intracellular Mature Vaccinia Virus: Thin-Section Analyses

Journal of Virology ◽

10.1128/jvi.75.22.11056-11070.2001 ◽

2001 ◽

Vol 75 (22) ◽

pp. 11056-11070 ◽

Cited By ~ 51

Author(s):

Gareth Griffiths ◽

Norbert Roos ◽

Sybille Schleich ◽

Jacomine Krijnse Locker

Keyword(s):

Vaccinia Virus ◽

Thin Section ◽

Structural Organization ◽

Integral Membrane Proteins ◽

Thin Sections ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Infected Cells ◽

Preceding Study ◽

Section Electron Microscopy

ABSTRACT In the preceding study (see accompanying paper), we showed by a variety of different techniques that intracellular mature vaccinia virus (vaccinia IMV) is unexpectedly complex in its structural organization and that this complexity also extends to the underlying viral core, which is highly folded. With that analysis as a foundation, we now present different thin-section electron microscopy approaches for analyzing the IMV and the processes by which it is assembled in infected HeLa cells. We focus on conventional epoxy resin thin sections as well as cryosections to describe key intermediates in the assembly process. We took advantage of streptolysin O's ability to selectively permeabilize the plasma membrane of infected cells to improve membrane contrast, and we used antibodies against bone fide integral membrane proteins of the virus to unequivocally identify membrane profiles in thin sections. All of the images presented here can be rationalized with respect to the model put forward for the assembly of the IMV in the accompanying paper.

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Comparison of microtubules and microfilaments in Tipula iridescent virus-infected and uninfected cells

Canadian Journal of Biochemistry and Cell Biology ◽

10.1139/o85-073 ◽

1985 ◽

Vol 63 (6) ◽

pp. 543-552 ◽

Cited By ~ 5

Author(s):

Robert W. Seagull ◽

Peter E. Lee ◽

Monica Frosch

Keyword(s):

Virus Assembly ◽

Electron Microscopic ◽

Iridescent Virus ◽

Initial Stage ◽

Large Virus ◽

Infected Cells ◽

Specific Association ◽

Globular Cells ◽

Cytoskeletal Elements ◽

Microscopic Techniques

Microfilaments and microtubules were detected in Estigmene acrea virus-infected cells using fluorescent immunochemistry and in sections by electron microscopy. Twelve hours following infection of cells with Tipula iridescent virus, large virus assembly sites developed in the cytoplasm. The majority of infected cells exhibit no detectable changes in the cytoskeleton during the initial stage of infection, when virus assembly sites are forming. Actin was localized either in cytoplasmic spikes or in patches at the cell surface. Microtubules were parallel to the long axis of elongate cells or randomly distributed in globular cells. Intermediate filaments were not detected using either immunofluorscent or electron microscopic techniques. In later stages of infection some cells exhibit a specific association between actin and the virus assembly site. The significance of this observation remains unclear since only a portion of the population exhibits this change. From this study, it does not appear that cytoskeletal elements are of importance in the formation or maintenance of the membrane-free cytoplasmic virus assembly sites.

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Formation and structure of root nodules induced on Macroptilium atropurpureum inoculated with various species of Rhizobium

Canadian Journal of Botany ◽

10.1139/b91-196 ◽

1991 ◽

Vol 69 (7) ◽

pp. 1520-1532 ◽

Cited By ~ 11

Author(s):

Michael J. Trinick ◽

Celia Miller ◽

Paul A. Hadobas

Keyword(s):

Rhizobium Leguminosarum ◽

Rhizobium Meliloti ◽

Root Nodules ◽

Matrix Material ◽

Immunogold Labelling ◽

Infection Threads ◽

Glass Tubes ◽

Infected Cells ◽

Macroptilium Atropurpureum ◽

Nodule Tissue

Fifteen strains of Rhizobium leguminosarum biovar trifolii formed ineffective nodules and (or) nodule-like structures (rhizobia were re-isolated from both structures) on Macroptilium atropurpureum grown in enclosed glass tubes. Bacteria were observed among the parenchyma cells surrounding the nodule-like structures. One variant of R. leguminosarum biovar trifolii (NGR66/ST) isolated from M. atropurpureum formed nodules on this host that exhibited abnormal intercellular and intracellular infection. The bacteria (NGR66/ST) were contained within threadlike structures, surrounded by matrix material. The identities of the Rhizobium strains were confirmed serologically after reisolation and in sections of nodule tissue using immunogold labelling. Rhizobium leguminosarum biovar phaseoli strain NGR76 isolated from Phaseolus vulgaris formed nodules on M. atropurpureum resembling those formed by effective Bradyrhizobium strains. The association was partially effective in nitrogen fixation, and this was reflected in the nodule structure. The percentage of cells infected was lower than that in fully effective nodules. There was a high frequency of infected cells showing degeneration; these were located throughout the nodule tissue and were often adjacent to healthy infected cells. The rhizobia appeared to infect new nodule cells via infection threads, which were abundant both intercellularly and intracellularly in young, mature, and degenerating host nodule cells. Strains of R. leguminosarum biovar viceae and Rhizobium meliloti were unable to induce nodule-like structures on M. atropurpureum. Key words: Macroptilium, Bradyrhizobium, Rhizobium, microscopy, nodule, structure.

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Histochemical evidence for the presence of a suberinlike compound in Rhizobium-induced nodules of the nonlegume Parasponia rigida

Canadian Journal of Botany ◽

10.1139/b86-200 ◽

1986 ◽

Vol 64 (7) ◽

pp. 1474-1483 ◽

Cited By ~ 15

Author(s):

Carol A. Smith ◽

Rachel C. Skvirsky ◽

Ann M. Hirsch

Keyword(s):

Periodic Acid ◽

Chemical Extraction ◽

Invasive Infection ◽

Cell Cytoplasm ◽

Sudan Black B ◽

Host Cell Cytoplasm ◽

Indeterminate Nodules ◽

Infection Threads ◽

Histochemical Evidence ◽

Nodule Tissue

Parasponia rigida (Ulmaceae) nodules, like nodules of pea and alfalfa, are elongate and cylindrical and of indeterminate morphology. However, unlike other indeterminate nodules, the Rhizobium (Rp501) endosymbiont is not released into the host cell cytoplasm and remains confined to threads. Two types of threads are found: invasive infection threads that traverse the nodule tissue intracellularly and intercellularly; and threads confined to the nodule cell, proliferating intracellularly, which are the presumed sites of nitrogen fixation. The thread walls contain pectic and cellulosic components as evidenced by periodic acid – Schiff’s staining and digestion with pectinase and cellulase. Using histochemical analyses coupled with enzymatic and chemical extraction, we determined that the walls of the intracellularly confined threads also contain a suberinlike compound. The thread walls stain positively with Sudan black B and other lipid stains. In contrast, the invasive infection threads appear to be lignified as well as suberized.

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Morphology of root nodules and nodule-like structures formed by Rhizobium and Agrobacterium strains containing a Rhizobium meliloti megaplasmid.

The Journal of Cell Biology ◽

10.1083/jcb.97.3.787 ◽

1983 ◽

Vol 97 (3) ◽

pp. 787-794 ◽

Cited By ~ 38

Author(s):

C H Wong ◽

C E Pankhurst ◽

A Kondorosi ◽

W J Broughton

Keyword(s):

Normal Development ◽

Rhizobium Meliloti ◽

Root Nodules ◽

Root Hairs ◽

Host Cells ◽

Donor Strain ◽

Intercellular Spaces ◽

Infection Threads ◽

Infected Cells ◽

Rhizobium Sp

We examined expression of the megaplasmid pRme41b of Rhizobium meliloti in two different Rhizobium sp. Strains and in Agrobacterium tumefaciens. Transfer of pRme41b into these bacteria was facilitated by insertion of a recombinant plasmid coding for mobilization functions of RP4 into the nif region (Kondorosi, A., E. Kondorosi, C.E. Pankhurst, W. J. Broughton, and Z. Banfalvi, 1982, Mol. Gen. Genet., 188:433-439). In all cases, transconjugants formed nodule-like structures on the roots of Medicago sativa. These structures were largely composed of meristematic cells but they were not invaded by bacteria. Bacteria were found only within infection threads in root hairs, and within intercellular spaces of the outermost cells of the structures. The donor strain of R. meliloti containing pAK11 or pAK12 in pRme41b initially produced nodules on M. sativa that did not fix nitrogen (Fix-). In these nodules, bacteria were released from infection threads into the host cells but they did not multiply appreciably. Any bacteroids formed degenerated prematurely. In some cases, however, reversion to a Fix+ phenotype occurred after 4 to 6 wk. Bacteria released into newly infected cells in these nodules showed normal development into bacteriods.

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Comparative cytochemical analysis of hydrogen peroxide distribution in pea ineffective mutant SGEFix--1 (sym40) and initial line SGE

Ecological genetics ◽

10.17816/ecogen733-9 ◽

2009 ◽

Vol 7 (3) ◽

pp. 3-9 ◽

Cited By ~ 4

Author(s):

Anna V Tsyganova ◽

Viktor E Tsyganov ◽

Aleksey U Borisov ◽

Igor A Tikhonovich ◽

Nicholas Brewin

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Cytochemical Analysis ◽

Infection Threads ◽

The Matrix ◽

Infected Cells ◽

Initial Line

Comparative cytochemical analysis has revealed differences in hydrogen peroxide distribution in symbiotic nodules of pea initial line SGE and mutant SGEFix--1 (sym40). In the initial line SGE, precipitates of cerium perhydroxide were deposited in the walls of infection threads and in adjacent material in the luminal matrix. In mutant SGEFix--1, an increased deposition of cerium perhydroxide precipitates was observed in the matrix of hypertrophied infection droplets, round bacteria contained in infection threads and also around juvenile bacteroids. The observed pattern of hydrogen peroxide distribution indicates that bacteria in infected cells of mutant nodules are exposed to a stronger oxidative stress compared with nodules of the initial line.

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