A plant plasma-membrane H+-ATPase promotes yeast TORC1 activation via its carboxy-terminal tail

AbstractThe Target of Rapamycin Complex 1 (TORC1) involved in coordination of cell growth and metabolism is highly conserved among eukaryotes. Yet the signals and mechanisms controlling its activity differ among taxa, according to their biological specificities. A common feature of fungal and plant cells, distinguishing them from animal cells, is that their plasma membrane contains a highly abundant H+-ATPase which establishes an electrochemical H+ gradient driving active nutrient transport. We have previously reported that in yeast, nutrient-uptake-coupled H+ influx elicits transient TORC1 activation and that the plasma-membrane H+-ATPase Pma1 plays an important role in this activation, involving more than just establishment of the H+ gradient. We show here that the PMA2 H+-ATPase from the plant Nicotiana plumbaginifolia can substitute for Pma1 in yeast, to promote H+-elicited TORC1 activation. This H+-ATPase is highly similar to Pma1 but has a longer carboxy-terminal tail binding 14–3–3 proteins. We report that a C-terminally truncated PMA2, which remains fully active, fails to promote H+-elicited TORC1 activation. Activation is also impaired when binding of PMA2 to 14–3–3 s is hindered. Our results show that at least some plant plasma-membrane H+-ATPases share with yeast Pma1 the ability to promote TORC1 activation in yeast upon H+-coupled nutrient uptake.

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Experimental Investigation of Effects of Extrusion Pressure on Cell Growth of Bioprinted Algae Cells in Green Bioprinting

Volume 1: Additive Manufacturing; Advanced Materials Manufacturing; Biomanufacturing; Life Cycle Engineering; Manufacturing Equipment and Automation ◽

10.1115/msec2020-8481 ◽

2020 ◽

Author(s):

Laura Jerpseth ◽

Ketan Thakare ◽

Zhijian Pei ◽

Hongmin Qin

Keyword(s):

Cell Growth ◽

Cell Count ◽

Plant Cells ◽

Extrusion Pressure ◽

Layer By Layer ◽

Animal Cells ◽

Physical Damage ◽

The Third ◽

Cell Counts ◽

The Difference

Abstract In bioprinting, biomaterials are deposited layer-by-layer to fabricate structures. Bioprinting has many potential applications in drug screening, tissue engineering, and regenerative medicine. Both animal cells and plant cells can be used to synthesize bioinks. Green bioprinting uses bioinks that have been synthesized using plant cells. Constructs fabricated via green bioprinting contain immobilized plant cells, with these cells arranged at desired locations. The constructs provide scaffolds for cell growth. Printing parameters affecting the growth of cells in green bioprinted constructs include print speed, needle diameter, extrusion temperature, and extrusion pressure. This paper reports a study to examine effects of extrusion pressure on cell growth (measured by cell count) in bioprinted constructs, using bioink containing Chlamydomonas reinhardtii algae cells. Three levels of extrusion pressure were used: 3, 5, and 7 bar. Cell counts in the bioprinted constructs were measured on the third and sixth days after bioprinting. It was found that, as extrusion pressure increased, cell count decreased on both the third and sixth days after bioprinting. Furthermore, the difference in cell counts between the third and the sixth days decreased as extrusion pressure increased. These trends suggest that increasing extrusion pressure during green bioprinting negatively affects cell growth. A possible reason for these trends is physical damage to or death of cells in the bioprinted constructs when extrusion pressure became higher.

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The Cell's Biological Rods and Ropes

MRS Bulletin ◽

10.1557/s0883769400053239 ◽

1999 ◽

Vol 24 (10) ◽

pp. 27-31 ◽

Cited By ~ 2

Author(s):

David Boal

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Chemical Composition ◽

Intermediate Filaments ◽

Plant Cells ◽

Cell Type ◽

Animal Cells ◽

Limited Variation ◽

A Cell ◽

Mechanical Elements

Despite a variety of shapes and sizes, the generic mechanical structure of cells is remarkably similar from one cell type to the next. All cells are bounded by a plasma membrane, a fluid sheet that controls the passage of materials into and out of the cell. Plant cells and bacteria reinforce this membrane with a cell wall, permitting the cell to operate at an elevated osmotic pressure. Simple cells, such as the bacterium shown in Figure 1a, possess a fairly homogeneous interior containing the cell's genetic blueprint and protein workhorses, but no mechanical elements. In contrast, as can be seen in Figure 1b, plant and animal cells contain internal compartments and a filamentous cytoskeleton—a network of biological ropes, cables, and poles that helps maintain the cell's shape and organize its contents.Four principal types of filaments are found in the cytoskeleton: spectrin, actin, microtubules, and a family of intermediate filaments. Not all filaments are present in all cells. The chemical composition of the filaments shows only limited variation from one cell to another, even in organisms as diverse as humans and yeasts. Membranes have a more variable composition, consisting of a bi-layer of dual-chain lipid molecules in which are embedded various proteins and frequently a moderate concentration of cholesterol. The similarity of the cell's mechanical elements in chemical composition and physical characteristics encourages us to search for universal strategies that have developed in nature for the engineering specifications of the cell. In this article, we concentrate on the cytoskeleton and its filaments.

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iDePP: a genetically encoded system for the inducible depletion of PI(4,5)P2 in Arabidopsis thaliana

10.1101/2020.05.13.091470 ◽

2020 ◽

Cited By ~ 1

Author(s):

Mehdi Doumane ◽

Léia Colin ◽

Alexis Lebecq ◽

Aurélie Fangain ◽

Joseph Bareille ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Plasma Membrane ◽

Protein Localization ◽

Cortical Microtubule ◽

Plant Cells ◽

Actin Dynamics ◽

Animal Cells ◽

Compensatory Mechanisms ◽

Microtubule Organization ◽

Membrane Contact Sites

ABSTRACTPhosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] is a low abundant lipid present at the plasma membrane of eukaryotic cells. Extensive studies in animal cells revealed the pleiotropic functions of PI(4,5)P2. In plant cells, PI(4,5)P2 is involved in various cellular processes including the regulation of cell polarity and tip growth, clathrin-mediated endocytosis, polar auxin transport, actin dynamics or membrane-contact sites. To date, most studies investigating the role of PI(4,5)P2 in plants have relied on mutants lacking enzymes responsible for PI(4,5)P2 synthesis and degradation. However, such genetic perturbations only allow steady-state analysis of plants undergoing their life cycle in PI(4,5)P2 deficient conditions and the corresponding mutants are likely to induce a range of non-causal (untargeted) effects driven by compensatory mechanisms. In addition, there are no small molecule inhibitors that are available in plants to specifically block the production of this lipid. Thus, there is currently no system to fine tune PI(4,5)P2 content in plant cells. Here we report a genetically encoded and inducible synthetic system, iDePP (Inducible Depletion of PI(4,5)P2 in Plants), that efficiently removes PI(4,5)P2 from the plasma membrane in different organs of Arabidopsis thaliana, including root meristem, root hair and shoot apical meristem. We show that iDePP allows the inducible depletion of PI(4,5)P2 in less than three hours. Using this strategy, we reveal that PI(4,5)P2 is critical for cortical microtubule organization. Together, we propose that iDePP is a simple and efficient genetic tool to test the importance of PI(4,5)P2 in given cellular or developmental responses but also to evaluate the importance of this lipid in protein localization.Research OrganismA. thaliana

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Faculty Opinions recommendation of A plant plasma-membrane H+-ATPase promotes yeast TORC1 activation via its carboxy-terminal tail.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.739637629.793585537 ◽

2021 ◽

Author(s):

Ramón Serrano

Keyword(s):

Plasma Membrane ◽

Carboxy Terminal ◽

Plant Plasma Membrane

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Experimental Investigation of Effects of Needle Diameter on Algae Cell Growth in Green Bioprinting

Volume 1: Additive Manufacturing; Advanced Materials Manufacturing; Biomanufacturing; Life Cycle Engineering; Manufacturing Equipment and Automation ◽

10.1115/msec2020-8480 ◽

2020 ◽

Author(s):

Ketan Thakare ◽

Laura Jerpseth ◽

Hongmin Qin ◽

Zhijian Pei

Keyword(s):

Cell Growth ◽

Chlamydomonas Reinhardtii ◽

Cell Count ◽

Plant Cells ◽

Future Research ◽

Great Promise ◽

Layer By Layer ◽

Animal Cells ◽

Plant Matter ◽

Needle Diameter

Abstract Bioprinting can fabricate structures based on layer-by-layer deposition of biomaterials. Bioprinting of animal cells shows great promise for tissue regeneration and tissue research. Plant cells can also be used when synthesizing bioink. Bioprinting with bioink that has been synthesized with plant cells instead of animal cells is called green bioprinting. Green bioprinting offers greater spatial control over the growth of plant matter by immobilizing cells. It is known that certain variables affect the growth and propagation (cellular reproduction) of cells in green bioprinted constructs post bioprinting. These variables include accessibility to components required for photosynthesis, such as nutrients, moisture and light. However, multiple parameters can also vary during the extrusion of bioink in the bioprinting process, including extrusion pressure, extrusion temperature, needle diameter, and printing speed. This paper reports a study to examine the effects of needle diameter during bioprinting on the growth of Chlamydomonas reinhardtii algae cells in green bioprinted constructs. Growth of Chlamydomonas reinhardtii algae cells was quantified by measuring cell count. The constructs were bioprinted with needle diameters of 22 gauge, 25 gauge, and 27 gauge. It was found that decreasing needle diameter was correlated with decreased cell count on the second and fifth days post bioprinting. Furthermore, the magnitude of cell count increase between the second and the fifth days post bioprinting decreased with decreasing needle diameter. Future research is needed to examine the effects of other printing parameters on cell growth.

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The yeast H+-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H+-coupled nutrient uptake

eLife ◽

10.7554/elife.31981 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 12

Author(s):

Elie Saliba ◽

Minoas Evangelinos ◽

Christos Gournas ◽

Florent Corrillon ◽

Isabelle Georis ◽

...

Keyword(s):

Amino Acids ◽

Plasma Membrane ◽

Amino Acid ◽

Nutrient Uptake ◽

Amino Acid Uptake ◽

Target Of Rapamycin ◽

Acid Uptake ◽

Export Activity

The yeast Target of Rapamycin Complex 1 (TORC1) plays a central role in controlling growth. How amino acids and other nutrients stimulate its activity via the Rag/Gtr GTPases remains poorly understood. We here report that the signal triggering Rag/Gtr-dependent TORC1 activation upon amino-acid uptake is the coupled H+ influx catalyzed by amino-acid/H+ symporters. H+-dependent uptake of other nutrients, ionophore-mediated H+ diffusion, and inhibition of the vacuolar V-ATPase also activate TORC1. As the increase in cytosolic H+ elicited by these processes stimulates the compensating H+-export activity of the plasma membrane H+-ATPase (Pma1), we have examined whether this major ATP-consuming enzyme might be involved in TORC1 control. We find that when the endogenous Pma1 is replaced with a plant H+-ATPase, H+ influx or increase fails to activate TORC1. Our results show that H+ influx coupled to nutrient uptake stimulates TORC1 activity and that Pma1 is a key actor in this mechanism.

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Localization of Adenosine Triphosphatase Activity in the Phleom of Nicotiana Tabacum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094401 ◽

1972 ◽

Vol 30 ◽

pp. 230-231

Author(s):

James Cronshaw ◽

Jamison E. Gilder

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Adenosine Triphosphatase ◽

Higher Plants ◽

High Surface ◽

Root Tip ◽

Animal Cells ◽

Physiological Processes ◽

Tip Cells ◽

Atpase Localization

Adenosine triphosphatase (ATPase) activity has been shown to be associated with numerous physiological processes in both plants and animal cells. Biochemical studies have shown that in higher plants ATPase activity is high in cell wall preparations and is associated with the plasma membrane, nuclei, mitochondria, chloroplasts and lysosomes. However, there have been only a few ATPase localization studies of higher plants at the electron microscope level. Poux (1967) demonstrated ATPase activity associated with most cellular organelles in the protoderm cells of Cucumis roots. Hall (1971) has demonstrated ATPase activity in root tip cells of Zea mays. There was high surface activity largely associated with the plasma membrane and plasmodesmata. ATPase activity was also demonstrated in mitochondria, dictyosomes, endoplasmic reticulum and plastids.

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