Mesosomes, Unique Membranous Structures in Bacteria

Mesosomes are unique membranous bacterial structures that actively function in cell injury and physiological cellular processes, such as replication and separation of nucleoids and oxidative phosphorylation. The structures and functions of mesosomes have been studied and identified, but the regulation of their functional properties remains still unclear. Our previous studies confirmed that hydrogen peroxide (H2O2) is involved in mesosome formation during cell injury and cell division processes. The quantity of excess H2O2accumulation is associated with the mesosome size. This observation has provided great significance in elucidating the mechanisms of maintainance of the functional performance of mesosomes. This article describes the bacterial mesosome and its functions as well as the involvement of H2O2in mediating these functions.

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Nothing Regular about the Regulins: Distinct Functional Properties of SERCA Transmembrane Peptide Regulatory Subunits

International Journal of Molecular Sciences ◽

10.3390/ijms22168891 ◽

2021 ◽

Vol 22 (16) ◽

pp. 8891

Author(s):

Nishadh Rathod ◽

Jessi J. Bak ◽

Joseph O. Primeau ◽

M’Lynn E. Fisher ◽

Lennane Michel Espinoza-Fonseca ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Functional Properties ◽

Transmembrane Helices ◽

Regulatory Subunits ◽

Reading Frame ◽

Endoplasmic Reticulum Calcium ◽

Cellular Processes ◽

Functional Consequences ◽

Differential Binding ◽

Dynamics Simulations

The sarco-endoplasmic reticulum calcium ATPase (SERCA) is responsible for maintaining calcium homeostasis in all eukaryotic cells by actively transporting calcium from the cytosol into the sarco-endoplasmic reticulum (SR/ER) lumen. Calcium is an important signaling ion, and the activity of SERCA is critical for a variety of cellular processes such as muscle contraction, neuronal activity, and energy metabolism. SERCA is regulated by several small transmembrane peptide subunits that are collectively known as the “regulins”. Phospholamban (PLN) and sarcolipin (SLN) are the original and most extensively studied members of the regulin family. PLN and SLN inhibit the calcium transport properties of SERCA and they are required for the proper functioning of cardiac and skeletal muscles, respectively. Myoregulin (MLN), dwarf open reading frame (DWORF), endoregulin (ELN), and another-regulin (ALN) are newly discovered tissue-specific regulators of SERCA. Herein, we compare the functional properties of the regulin family of SERCA transmembrane peptide subunits and consider their regulatory mechanisms in the context of the physiological and pathophysiological roles of these peptides. We present new functional data for human MLN, ELN, and ALN, demonstrating that they are inhibitors of SERCA with distinct functional consequences. Molecular modeling and molecular dynamics simulations of SERCA in complex with the transmembrane domains of MLN and ALN provide insights into how differential binding to the so-called inhibitory groove of SERCA—formed by transmembrane helices M2, M6, and M9—can result in distinct functional outcomes.

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Doping by Design: Finding New n-type Dopable ABX4 Zintl Phases for Thermoelectrics

10.26434/chemrxiv.12844655.v1 ◽

2020 ◽

Author(s):

Jiaxing Qu ◽

Vladan Stevanovic ◽

Elif Ertekin ◽

Prashun Gorai

Keyword(s):

Functional Properties ◽

Functional Performance ◽

Functional Materials ◽

Design Strategy ◽

Computational Approach ◽

New Materials ◽

Zintl Phases ◽

Prototype Structure ◽

New Compounds

Doping remains a bottleneck in discovering novel functional materials for applications such as thermoelectrics (TE) and photovoltaics. The current computational approach to materials discovery is to identify candidates by predicting the functional properties of a pool of known materials, and hope that the candidates can be appropriately doped. What if we could "design" new materials that have the desired functionalities and doping properties? In this work, we use an approach, wherein we perform chemical replacements in a prototype structure, to realize doping by design. We hypothesize that the doping characteristics and functional performance of the prototype structure are translated to the new compounds created by chemical replacements. Discovery of new n-type Zintl phases is desirable for TE; however, n-type Zintl phases are a rarity. We demonstrate our doping design strategy by discovering 7 new, previously-unreported ABX4 Zintl phases that adopt the prototypical KGaSb4 structure. Among the new phases, we computationally confirm that NaAlSb4, NaGaSb4 and CsInSb4 are n-type dopable and potentially exhibit high n-type TE performance, even exceeding that of KGaSb4. Our structure prototyping approach offers a promising route to discover new materials with designed doping and functional properties.

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Regulation of morphological and functional properties of astrocytes by hydrogen peroxide

Cell and Tissue Biology ◽

10.1134/s1990519x07010026 ◽

2007 ◽

Vol 1 (1) ◽

pp. 8-13 ◽

Cited By ~ 1

Author(s):

T. A. Kulahava ◽

G. N. Semenkova ◽

Z. B. Kvacheva ◽

S. N. Cherenkevich

Keyword(s):

Hydrogen Peroxide ◽

Functional Properties

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Lipid Cell Biology: A Focus on Lipids in Cell Division

Annual Review of Biochemistry ◽

10.1146/annurev-biochem-062917-012448 ◽

2018 ◽

Vol 87 (1) ◽

pp. 839-869 ◽

Cited By ~ 24

Author(s):

Elisabeth M. Storck ◽

Cagakan Özbalci ◽

Ulrike S. Eggert

Keyword(s):

Mass Spectrometry ◽

Cell Division ◽

Cell Biology ◽

Chemical Biology ◽

Structural Integrity ◽

Advanced Imaging ◽

Functional Roles ◽

Lipid Interactions ◽

Cellular Processes ◽

Alkyl Side Chains

Cells depend on hugely diverse lipidomes for many functions. The actions and structural integrity of the plasma membrane and most organelles also critically depend on membranes and their lipid components. Despite the biological importance of lipids, our understanding of lipid engagement, especially the roles of lipid hydrophobic alkyl side chains, in key cellular processes is still developing. Emerging research has begun to dissect the importance of lipids in intricate events such as cell division. This review discusses how these structurally diverse biomolecules are spatially and temporally regulated during cell division, with a focus on cytokinesis. We analyze how lipids facilitate changes in cellular morphology during division and how they participate in key signaling events. We identify which cytokinesis proteins are associated with membranes, suggesting lipid interactions. More broadly, we highlight key unaddressed questions in lipid cell biology and techniques, including mass spectrometry, advanced imaging, and chemical biology, which will help us gain insights into the functional roles of lipids.

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Thermal cycling protects SH-SY5Y cells against hydrogen peroxide and β-amyloid-induced cell injury through stress response mechanisms involving Akt pathway

PLoS ONE ◽

10.1371/journal.pone.0240022 ◽

2020 ◽

Vol 15 (10) ◽

pp. e0240022

Author(s):

Wei-Ting Chen ◽

Yu-Yi Kuo ◽

Guan-Bo Lin ◽

Chueh-Hsuan Lu ◽

Hao-Ping Hsu ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Stress Response ◽

Thermal Cycling ◽

Cell Injury ◽

Akt Pathway ◽

Β Amyloid

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Structure and functional properties of protein from defatted Camellia oleifera seed cake: Effect of hydrogen peroxide decolorization

International Journal of Food Properties ◽

10.1080/10942912.2019.1642355 ◽

2019 ◽

Vol 22 (1) ◽

pp. 1283-1295 ◽

Cited By ~ 3

Author(s):

Guang-Long Yao ◽

Wei He ◽

You-Gen Wu ◽

Jian Chen ◽

Xin-Wen Hu ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Functional Properties ◽

Camellia Oleifera ◽

Seed Cake

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Regulation of cell cycle drivers by Cullin-RING ubiquitin ligases

Experimental & Molecular Medicine ◽

10.1038/s12276-020-00508-4 ◽

2020 ◽

Vol 52 (10) ◽

pp. 1637-1651 ◽

Cited By ~ 1

Author(s):

Sang-Min Jang ◽

Christophe E. Redon ◽

Bhushan L. Thakur ◽

Meriam K. Bahta ◽

Mirit I. Aladjem

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Cell Cycle Progression ◽

Ubiquitin Ligases ◽

Anaphase Promoting Complex ◽

Cycle Progression ◽

Cellular Processes ◽

Cellular Pathways ◽

Regulation Of Cell Cycle ◽

F Box Protein

Abstract The last decade has revealed new roles for Cullin-RING ubiquitin ligases (CRLs) in a myriad of cellular processes, including cell cycle progression. In addition to CRL1, also named SCF (SKP1-Cullin 1-F box protein), which has been known for decades as an important factor in the regulation of the cell cycle, it is now evident that all eight CRL family members are involved in the intricate cellular pathways driving cell cycle progression. In this review, we summarize the structure of CRLs and their functions in driving the cell cycle. We focus on how CRLs target key proteins for degradation or otherwise alter their functions to control the progression over the various cell cycle phases leading to cell division. We also summarize how CRLs and the anaphase-promoting complex/cyclosome (APC/C) ligase complex closely cooperate to govern efficient cell cycle progression.

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A novel landscape of nuclear human CDK2 substrates revealed by in situ phosphorylation

Science Advances ◽

10.1126/sciadv.aaz9899 ◽

2020 ◽

Vol 6 (16) ◽

pp. eaaz9899

Author(s):

Yong Chi ◽

John H. Carter ◽

Jherek Swanger ◽

Alexander V. Mazin ◽

Robert L. Moritz ◽

...

Keyword(s):

Cell Division ◽

Protein Complexes ◽

Nuclear Architecture ◽

Cyclin Dependent Kinase ◽

Oncogenic Signaling ◽

Cellular Processes ◽

Validation Rate ◽

Associated Proteins ◽

Epigenetic Regulators

Cyclin-dependent kinase 2 (CDK2) controls cell division and is central to oncogenic signaling. We used an “in situ” approach to identify CDK2 substrates within nuclei isolated from cells expressing CDK2 engineered to use adenosine 5′-triphosphate analogs. We identified 117 candidate substrates, ~40% of which are known CDK substrates. Previously unknown candidates were validated to be CDK2 substrates, including LSD1, DOT1L, and Rad54. The identification of many chromatin-associated proteins may have been facilitated by labeling conditions that preserved nuclear architecture and physiologic CDK2 regulation by endogenous cyclins. Candidate substrates include proteins that regulate histone modifications, chromatin, transcription, and RNA/DNA metabolism. Many of these proteins also coexist in multi-protein complexes, including epigenetic regulators, that may provide new links between cell division and other cellular processes mediated by CDK2. In situ phosphorylation thus revealed candidate substrates with a high validation rate and should be readily applicable to other nuclear kinases.

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