Mitochondrial temperature homeostasis resists external metabolic stresses

eLife, Journal Year: 2023, Volume and Issue: 12

Published: July 4, 2023

Based on studies with a fluorescent reporter dye, Mito Thermo Yellow (MTY), and the genetically encoded gTEMP ratiometric temperature indicator targeted to mitochondria, of active mitochondria in four mammalian one insect cell line was estimated be up 15°C above that external environment which cells were exposed. High mitochondrial maintained face variety metabolic stresses, including substrate starvation or modification, decreased ATP demand due inhibition cytosolic protein synthesis, adenine nucleotide transporter and, if an auxiliary pathway for electron transfer available via alternative oxidase, even respiratory poisons acting downstream oxidative phosphorylation (OXPHOS) complex I. We propose high is inescapable consequence biochemistry OXPHOS homeostatically as primary feature metabolism.

Language: Английский

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Infrared laser–induced gene expression in single cells characterized by quantitative imaging in Physcomitrium patens

Communications Biology, Journal Year: 2024, Volume and Issue: 7(1)

Published: Nov. 6, 2024

A spatiotemporal understanding of gene function requires the precise control expression in each cell. Here, we use an infrared laser–evoked operator (IR-LEGO) system to induce at single-cell level moss Physcomitrium patens by heating a living cell with IR laser and thereby activating heat shock response. We identify irradiation conditions that provide higher inducibility lower invasiveness changing power duration. Furthermore, quantitatively characterize induction profile response using heat-induced fluorescence reporter after single cells under different conditions. Our data indicate long duration leads according increase but not vice versa, even without conferring apparent damage decelerates and/or delayed induction. define temporal shift as onset This study contributes versatile application IR-LEGO plants improves our shock-induced expression. optimizes effectively inducing characterizes through quantitative imaging analysis patens.

Language: Английский

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Real-Time Temperature Sensing Using a Ratiometric Dual Fluorescent Protein Biosensor

Biosensors, Journal Year: 2023, Volume and Issue: 13(3), P. 338 - 338

Published: March 3, 2023

Accurate temperature control within biological and chemical reaction samples instrument calibration are essential to the diagnostic, pharmaceutical industries. This is particularly challenging for microlitre-scale reactions typically used in real-time PCR applications differential scanning fluorometry. Here, we describe development of a simple, inexpensive ratiometric dual fluorescent protein biosensor (DFPTB). A combination cycle three green monomeric red enabled quantification relative changes identification discrepancies across wide range 4-70 °C. The maximal sensitivity 6.7% °C-1 precision 0.1 °C were achieved biologically relevant 25-42 standard phosphate-buffered saline conditions at pH 7.2. Good was variety buffers ranging from 4.8 9.1. DFPTB can be either purified or mixed bacteria-encapsulated formats, paving way vitro vivo topologically precise measurements.

Language: Английский

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Neural Networks Push the Limits of Luminescence Lifetime Nanosensing

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(52)

Published: Oct. 3, 2023

Abstract Luminescence lifetime‐based sensing is ideally suited to monitor biological systems due its minimal invasiveness and remote working principle. Yet, applicability limited in conditions of low signal‐to‐noise ratio (SNR) induced by, e.g., short exposure times presence opaque tissues. Herein this limitation overcome by applying a U‐shaped convolutional neural network (U‐NET) improve luminescence lifetime estimation under extremely SNR. Specifically, the prowess U‐NET showcased context thermometry, achieving more precise thermal readouts using Ag 2 S nanothermometers. Compared traditional analysis methods decay curve fitting integration, can extract average lifetimes precisely consistently regardless SNR value. The improvement achieved performance demonstrated with two experiments characterized extreme measurement conditions: monitoring free‐falling droplets, transients suspended droplets through an medium. These results broaden fields including vivo experimentation microfluidics, while, hopefully, spurring further research on implementation machine learning (ML) sensing.

Language: Английский

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Quantum nanodiamonds for sensing of biological quantities: Angle, temperature, and thermal conductivity

Biophysics and Physicobiology, Journal Year: 2022, Volume and Issue: 19(0), P. n/a - n/a

Published: Jan. 1, 2022

Measuring physical quantities in the nanometric region inside single cells is of great importance for understanding cellular activity. Thus, development biocompatible, sensitive, and reliable nanobiosensors essential progress biological research. Diamond nanoparticles containing nitrogen-vacancy centers (NVCs), referred to as fluorescent nanodiamonds (FNDs), have recently emerged sensors that show promise ultrasensitive nanosensing quantities. FNDs emit stable fluorescence without photobleaching. Additionally, their distinctive magneto-optical properties enable an optical readout quantum states electron spin NVC under ambient conditions. These quantitative sensing parameters (temperature, magnetic field, electric pH, etc.) vicinity FND; hence, are often described "quantum sensors". In this review, recent advancements biosensing applications summarized. First, principles orientation temperature using FND explained. Next, we introduce surface coating techniques indispensable controlling physicochemical FNDs. The achievements practical surface-coated FNDs, including orientation, temperature, thermal conductivity, then highlighted. Finally, advantages, challenges, perspectives discussed. This review article extended version Japanese article, Situ Measurement Intracellular Thermal Conductivity Using Nanoparticle, published SEIBUTSU BUTSURI Vol. 62, p. 122-124 (2022).

Language: Английский

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Cardiomyocyte Heat Production Measured In Vitro with Temperature Probes and by Means of Differential Isothermal Calorimetry Indicates a Role of the ABA/LANCL1-2 Hormone/Receptors System in Thermogenesis

Published: Feb. 20, 2024

Abscisic acid (ABA) is a conserved “stress hormone” in unicellular organisms, plants and animals. In mammals, ABA its receptors LANCL1 LANCL2 stimulate insulin-independent cell glucose uptake oxidative metabolism: overexpression of LANCL1/2 increases, their si-lencing conversely reduces, mitochondrial number, respiration proton gradient dissipation muscle cells brown adipocytes. We hypothesized that the ABA/LANCL hor-mone/receptors system could be involved thermogenesis. Heat production by LANCL1/2-overexpressing vs. double-silenced was compared rat H9c2 cardiomyocytes with two different methods: differential temperature measurements using sensitive thermistor probes, isothermal calorimetry. Results indicate overexpressing generate an approx. double amount thermal power cells, addition further doubles heat cells. With we find time-scale 4 min for thermogenesis to “turn on” after nutrient addition. These results identify hormone as hitherto unknown regu-lator Pharmacologic means increasing metabolic energy are considered promising strategy reduce stress lipid accumulation at cellular organismic level: from this study, LANCL1-2 proteins emerge targetable controllers ther-mogenesis through natural ligand ABA.

Language: Английский

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Fluorescent Microscopy of Hot Spots Induced by Laser Heating of Iron Oxide Nanoparticles

Photonics, Journal Year: 2023, Volume and Issue: 10(7), P. 705 - 705

Published: June 21, 2023

Determination of the iron oxide nanoparticles (IONPs) local temperature during laser heating is important in aspect phototherapy. We have carried out theoretical modeling IONPs electromagnetic (EM) field enhancement and under action near individual ensembles with different sizes, shapes chemical phases. For experimental determination temperature, we used fluorescence thermometry rhodamine B (RhB) based on its lifetime. Depending shape their location space, a significant change spatial distribution EM surface observed. The an ensemble reaches sufficiently high values; relative about 35 °C for Fe2O3 NPs. Nevertheless, all studied water colloids showed by no more than 10 °C. depends thermal conductivity medium, which heat dissipation depends. During scanning cell culture incubated types IONPs, increase, estimated from shortening RhB lifetime, 100 Such “hot spots” within lysosomes, where predominantly reside, lead to severe cellular stress can be therapy.

Language: Английский

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Energy Transfer Characteristics of Lipid Bilayer Membranes of Liposomes Examined with Picosecond Time-Resolved Raman Spectroscopy

The Journal of Physical Chemistry B, Journal Year: 2023, Volume and Issue: 127(30), P. 6684 - 6693

Published: July 23, 2023

A number of biochemical reactions proceed inside biomembranes. Since the rate a chemical reaction is influenced by properties surrounding environment, it important to examine environment Although energy transfer characteristics are basic and property medium, experimental investigation thermal conducting capabilities biomembranes challenging task. We have examined lipid bilayer membranes liposomes, good model system for biomembrane, with picosecond time-resolved Raman spectroscopy. The cooling kinetics first excited singlet (S1) state trans-stilbene solubilized within observed as peak shift 1570 cm–1 band S1 trans-stilbene. constant obtained in six formed phospholipids different hydrocarbon chains, DSPC, DPPC, DMPC, DLPC, DOPC, egg-PC. estimate diffusivity known correlation between solvent. estimated liquid-crystal-phase 8.9 × 10–8 9.4 m2 s–1, while that gel-phase 8.4 8.5 s–1. difference two phases explained one-dimensional diffusion equation heat.

Language: Английский

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Mitochondrial temperature homeostasis resists external metabolic stresses

Published: July 4, 2023

Based on studies with a fluorescent reporter dye, Mito Thermo Yellow, and the genetically encoded gTEMP ratiometric temperature indicator targeted to mitochondria, of active mitochondria in four mammalian one insect cell-line was estimated be up 15 °C above that external environment which cells were exposed. High mitochondrial maintained face variety metabolic stresses, including substrate starvation or modification, decreased ATP demand due inhibition cytosolic protein synthesis, adenine nucleotide transporter and, if an auxiliary pathway for electron transfer available via alternative oxidase, even respiratory poisons acting downstream complex I. We propose high is inescapable consequence biochemistry oxidative phosphorylation homeostatically as primary feature metabolism.Mitochondria are at least hotter than their living cells. In response diverse re-adjusts this value whenever possible.

Language: Английский

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Mitochondrial temperature homeostasis resists external metabolic stresses

Published: Nov. 13, 2023

Based on studies with a fluorescent reporter dye, Mito Thermo Yellow, and the genetically encoded gTEMP ratiometric temperature indicator targeted to mitochondria, of active mitochondria in four mammalian one insect cell-line was estimated be up 15 °C above that external environment which cells were exposed. High mitochondrial maintained face variety metabolic stresses, including substrate starvation or modification, decreased ATP demand due inhibition cytosolic protein synthesis, adenine nucleotide transporter and, if an auxiliary pathway for electron transfer available via alternative oxidase, even respiratory poisons acting downstream OXPHOS complex I. We propose high is inescapable consequence biochemistry oxidative phosphorylation homeostatically as primary feature metabolism.Mitochondria are hotter than their living cells. In response diverse re-adjusts this value whenever possible.

Language: Английский

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