1
|
Zhou W, Xiao RY, Yang YX, Wang X, Wang DH, Wang ZZ. Clock protein LHY targets SNAT1 and negatively regulates the biosynthesis of melatonin in Hypericum perforatum. SCIENCE ADVANCES 2024; 10:eadq6505. [PMID: 39292789 PMCID: PMC11409971 DOI: 10.1126/sciadv.adq6505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Accepted: 08/12/2024] [Indexed: 09/20/2024]
Abstract
Hypericum perforatum, also known as "natural fluoxetine," is a commonly used herbal remedy for treating depression. It is unclear whether melatonin in plants regulated by the endogenous circadian clock system is like in vertebrates. In this work, we found that the melatonin signal and melatonin biosynthesis gene, serotonin N-acetyltransferase HpSNAT1, oscillates in a 24-hour cycle in H. perforatum. First, we constructed a yeast complementary DNA library of H. perforatum and found a clock protein HpLHY that can directly bind to the HpSNAT1 promoter. Second, it was confirmed that HpLHY inhibits the expression of HpSNAT1 by targeting the Evening Element. Last, it indicated that HpLHY-overexpressing plants had reduced levels of melatonin in 12-hour light/12-hour dark cycle photoperiod, while loss-of-function mutants exhibited high levels, but this rhythm seems to disappear as well. The results revealed the regulatory role of LHY in melatonin biosynthesis, which may make an important contribution to the field of melatonin synthesis regulation.
Collapse
Affiliation(s)
- Wen Zhou
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| | - Ru-Yi Xiao
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| | - Yi-Xiao Yang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| | - Xue Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| | - Dong-hao Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| | - Zhe-zhi Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Shaanxi Normal University, Xi’ an 710062, China
| |
Collapse
|
2
|
Lledos M, Calatayud DG, Cortezon-Tamarit F, Ge H, Pourzand C, Botchway SW, Sodupe M, Lledós A, Eggleston IM, Pascu SI. Tripodal BODIPY-Tagged and Functional Molecular Probes: Synthesis, Computational Investigations and Explorations by Multiphoton Fluorescence Lifetime Imaging Microscopy. Chemistry 2024; 30:e202400858. [PMID: 38887133 DOI: 10.1002/chem.202400858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 06/15/2024] [Accepted: 06/17/2024] [Indexed: 06/20/2024]
Abstract
A range of novel BODIPY derivatives with a tripodal aromatic core was synthesized and characterized spectroscopically. These new fluorophores showed promising features as probes for in vitro assays in live cells and offer strategic routes for further functionalization towards hybrid nanomaterials. Incorporation of biotin tags facilitated proof-of-concept access to targeted bioconjugates as molecular probes. Computational explorations using DFT and TD-DFT calculations identified the most stable tripodal linker conformations and predicted their absorption and emission behavior. The uptake and speciation of these molecules in living prostate cancer cells was imaged by single- and two-photon excitation techniques coupled with two-photon fluorescence lifetime imaging (2P FLIM).
Collapse
Affiliation(s)
- Marina Lledos
- Department of Chemistry, University of Bath, Bath, BA2 7AY, U.K
| | - David G Calatayud
- Department of Inorganic Chemistry, Universidad Autonoma de Madrid, Francisco Tomas y Valiente 7, 28049, Madrid, Spain
| | | | - Haobo Ge
- Department of Chemistry, University of Bath, Bath, BA2 7AY, U.K
- Department of Life Sciences, University of Bath, BA2 7AY, Bath, UK
| | - Charareh Pourzand
- Department of Life Sciences, University of Bath, BA2 7AY, Bath, UK
- Centre for Therapeutic Innovation, University of Bath, BA2 7AY, Bath, UK
| | - Stanley W Botchway
- STFC Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell, Science and Innovation Campus, Harwell, Oxfordshire, OX11 0QX, UK
| | - Mariona Sodupe
- Departament de Química, Universitat Autònoma de Barcelona Cerdanyola del Vallès, 08193, Barcelona, Spain
| | - Agustí Lledós
- Departament de Química, Universitat Autònoma de Barcelona Cerdanyola del Vallès, 08193, Barcelona, Spain
| | - Ian M Eggleston
- Department of Life Sciences, University of Bath, BA2 7AY, Bath, UK
- Centre for Therapeutic Innovation, University of Bath, BA2 7AY, Bath, UK
| | - Sofia I Pascu
- Department of Chemistry, University of Bath, Bath, BA2 7AY, U.K
- Centre for Therapeutic Innovation, University of Bath, BA2 7AY, Bath, UK
| |
Collapse
|
3
|
Smith HE, Mackenzie AM, Seddon C, Mould R, Kalampouka I, Malakar P, Needham SR, Beis K, Bell JD, Nunn A, Botchway SW. The use of NADH anisotropy to investigate mitochondrial cristae alignment. Sci Rep 2024; 14:5980. [PMID: 38472304 DOI: 10.1038/s41598-024-55780-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
Life may be expressed as the flow of electrons, protons, and other ions, resulting in large potential difference. It is also highly photo-sensitive, as a large proportion of the redox capable molecules it relies on are chromophoric. It is thus suggestive that a key organelle in eukaryotes, the mitochondrion, constantly adapt their morphology as part of the homeostatic process. Studying unstained in vivo nano-scale structure in live cells is technically very challenging. One option is to study a central electron carrier in metabolism, reduced nicotinamide adenine dinucleotide (NADH), which is fluorescent and mostly located within mitochondria. Using one and two-photon absorption (340-360 nm and 730 nm, respectively), fluorescence lifetime imaging and anisotropy spectroscopy of NADH in solution and in live cells, we show that mitochondria do indeed appear to be aligned and exhibit high anisotropy (asymmetric directionality). Aqueous solution of NADH showed an anisotropy of ~ 0.20 compared to fluorescein or coumarin of < 0.1 and 0.04 in water respectively and as expected for small organic molecules. The anisotropy of NADH also increased further to 0.30 in the presence of proteins and 0.42 in glycerol (restricted environment) following two-photon excitation, suggesting more ordered structures. Two-photon NADH fluorescence imaging of Michigan Cancer Foundation-7 (MCF7) also showed strong anisotropy of 0.25 to 0.45. NADH has a quantum yield of fluorescence of 2% compared to more than 40% for photoionisation (electron generation), when exposed to light at 360 nm and below. The consequence of such highly ordered and directional NADH patterns with respect to electron ejection upon ultra-violet (UV) excitation could be very informative-especially in relation to ascertaining the extent of quantum effects in biology, including electron and photonic cascade, communication and modulation of effects such as spin and tunnelling.
Collapse
Affiliation(s)
- Holly E Smith
- UKRI, STFC, Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK
| | - Alasdair M Mackenzie
- UKRI, STFC, Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK
| | - Chloe Seddon
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
- Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, Oxfordshire, OX11 0FA, UK
| | - Rhys Mould
- School of Life Sciences, Research Centre for Optimal Health, University of Westminster, London, W1W 6UW, UK
| | - Ifi Kalampouka
- School of Life Sciences, Research Centre for Optimal Health, University of Westminster, London, W1W 6UW, UK
| | - Partha Malakar
- UKRI, STFC, Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK
| | - Sarah R Needham
- UKRI, STFC, Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK
| | - Konstantinos Beis
- Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
- Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, Oxfordshire, OX11 0FA, UK
| | - Jimmy D Bell
- School of Life Sciences, Research Centre for Optimal Health, University of Westminster, London, W1W 6UW, UK
| | - Alistair Nunn
- School of Life Sciences, Research Centre for Optimal Health, University of Westminster, London, W1W 6UW, UK
| | - Stanley W Botchway
- UKRI, STFC, Central Laser Facility, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK.
| |
Collapse
|
4
|
Kriechbaumer V, Botchway SW. Immunoprecipitation and FRET-FLIM to Determine Metabolons on the Plant ER. Methods Mol Biol 2024; 2772:169-177. [PMID: 38411813 DOI: 10.1007/978-1-0716-3710-4_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Metabolons are protein complexes that contain all the enzymes necessary for a metabolic pathway but also scaffolding proteins. Such a structure allows efficient channeling of intermediate metabolites form one active site to the next and is highly advantageous for labile or toxic intermediates. Here we describe two methods currently used to identify metabolons via protein-protein interaction methodology: immunoprecipitations using GFP-Trap®_A beads to find novel interaction partners and potential metabolon components and FRET-FLIM to test for and quantify protein-protein interactions in planta.
Collapse
Affiliation(s)
- Verena Kriechbaumer
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, UK
| |
Collapse
|
5
|
Spatola Rossi T, Tolmie AF, Nichol T, Pain C, Harrison P, Smith TJ, Fricker M, Kriechbaumer V. Recombinant expression and subcellular targeting of the particulate methane monooxygenase (pMMO) protein components in plants. Sci Rep 2023; 13:15337. [PMID: 37714899 PMCID: PMC10504283 DOI: 10.1038/s41598-023-42224-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 09/07/2023] [Indexed: 09/17/2023] Open
Abstract
Methane is a potent greenhouse gas, which has contributed to approximately a fifth of global warming since pre-industrial times. The agricultural sector produces significant methane emissions, especially from livestock, waste management and rice cultivation. Rice fields alone generate around 9% of total anthropogenic emissions. Methane is produced in waterlogged paddy fields by methanogenic archaea, and transported to the atmosphere through the aerenchyma tissue of rice plants. Thus, bioengineering rice with catalysts to detoxify methane en route could contribute to an efficient emission mitigation strategy. Particulate methane monooxygenase (pMMO) is the predominant methane catalyst found in nature, and is an enzyme complex expressed by methanotrophic bacteria. Recombinant expression of pMMO has been challenging, potentially due to its membrane localization, multimeric structure, and polycistronic operon. Here we show the first steps towards the engineering of plants for methane detoxification with the three pMMO subunits expressed in the model systems tobacco and Arabidopsis. Membrane topology and protein-protein interactions were consistent with correct folding and assembly of the pMMO subunits on the plant ER. Moreover, a synthetic self-cleaving polypeptide resulted in simultaneous expression of all three subunits, although low expression levels precluded more detailed structural investigation. The work presents plant cells as a novel heterologous system for pMMO allowing for protein expression and modification.
Collapse
Affiliation(s)
- Tatiana Spatola Rossi
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - A Frances Tolmie
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - Tim Nichol
- Molecular Microbiology Research Group, Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, S1 1WB, UK
| | - Charlotte Pain
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - Patrick Harrison
- Department of Biological and Marine Sciences, University of Hull, Hull, HU6 7RX, UK
| | - Thomas J Smith
- Molecular Microbiology Research Group, Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, S1 1WB, UK
| | - Mark Fricker
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK
| | - Verena Kriechbaumer
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK.
- Centre for Bioimaging, Oxford Brookes University, Oxford, UK.
| |
Collapse
|
6
|
Eastwood TA, Baker K, Streather BR, Allen N, Wang L, Botchway SW, Brown IR, Hiscock JR, Lennon C, Mulvihill DP. High-yield vesicle-packaged recombinant protein production from E. coli. CELL REPORTS METHODS 2023; 3:100396. [PMID: 36936078 PMCID: PMC10014274 DOI: 10.1016/j.crmeth.2023.100396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/08/2022] [Accepted: 01/09/2023] [Indexed: 02/05/2023]
Abstract
We describe an innovative system that exports diverse recombinant proteins in membrane-bound vesicles from E. coli. These recombinant vesicles compartmentalize proteins within a micro-environment that enables production of otherwise challenging insoluble, toxic, or disulfide-bond containing proteins from bacteria. The release of vesicle-packaged proteins supports isolation from the culture and allows long-term storage of active protein. This technology results in high yields of vesicle-packaged, functional proteins for efficient downstream processing for a wide range of applications from discovery science to applied biotechnology and medicine.
Collapse
Affiliation(s)
- Tara A. Eastwood
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Karen Baker
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Bree R. Streather
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Nyasha Allen
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
- School of Chemistry and Forensics, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Lin Wang
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell, Didcot, Oxford OX11 0QX, UK
| | - Stanley W. Botchway
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell, Didcot, Oxford OX11 0QX, UK
| | - Ian R. Brown
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Jennifer R. Hiscock
- School of Chemistry and Forensics, University of Kent, Canterbury, Kent CT2 7NJ, UK
| | - Christopher Lennon
- Fujifilm-Diosynth Biotechnologies UK, Ltd., Belasis Avenue, Billingham TS23 1LH, UK
| | | |
Collapse
|
7
|
Fluorescence and phosphorescence lifetime imaging reveals a significant cell nuclear viscosity and refractive index changes upon DNA damage. Sci Rep 2023; 13:422. [PMID: 36624137 PMCID: PMC9829731 DOI: 10.1038/s41598-022-26880-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/20/2022] [Indexed: 01/11/2023] Open
Abstract
Cytoplasmic viscosity is a crucial parameter in determining rates of diffusion-limited reactions. Changes in viscosity are associated with several diseases, whilst nuclear viscosity determines gene integrity, regulation and expression. Yet how drugs including DNA-damaging agents affect viscosity is unknown. We demonstrate the use of a platinum complex, Pt[L]Cl, that localizes efficiently mostly in the nucleus as a probe for nuclear viscosity. The phosphorescence lifetime of Pt[L]Cl is sensitive to viscosity and provides an excellent tool to investigate the impact of DNA damage. We show using Fluorescence Lifetime Imaging (FLIM) that the lifetime of both green and red fluorescent proteins (FP) are also sensitive to changes in cellular viscosity and refractive index. However, Pt[L]Cl proved to be a more sensitive viscosity probe, by virtue of microsecond phosphorescence lifetime versus nanosecond fluorescence lifetime of FP, hence greater sensitivity to bimolecular reactions. DNA damage was inflicted by either a two-photon excitation, one-photon excitation microbeam and X-rays. DNA damage of live cells causes significant increase in the lifetime of either Pt[L]Cl (HeLa cells, 12.5-14.1 µs) or intracellularly expressed mCherry (HEK293 cells, 1.54-1.67 ns), but a decrease in fluorescence lifetime of GFP from 2.65 to 2.29 ns (in V15B cells). These values represent a viscosity change from 8.59 to 20.56 cP as well as significant changes in the refractive index (RI), according to independent calibration. Interestingly DNA damage localized to a submicron region following a laser microbeam induction showed a whole cell viscosity change, with those in the nucleus being greater than the cytoplasm. We also found evidence of a by-stander effect, whereby adjacent un-irradiated cells also showed nuclear viscosity change. Finally, an increase in viscosity following DNA damage was also observed in bacterial cells with an over-expressed mNeonGreen FP, evidenced by the change in its lifetime from 2.8 to 2.4 ns.
Collapse
|
8
|
Spatola Rossi T, Pain C, Botchway SW, Kriechbaumer V. FRET-FLIM to Determine Protein Interactions and Membrane Topology of Enzyme Complexes. Curr Protoc 2022; 2:e598. [PMID: 36300920 DOI: 10.1002/cpz1.598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Determining protein-protein interactions is vital for gaining knowledge on cellular and metabolic processes including enzyme complexes and metabolons. Förster resonance energy transfer with fluorescence lifetime imaging microscopy (FRET-FLIM) is an advanced imaging methodology that allows for the quantitative detection of protein-protein interactions. In this method, proteins of interest for interaction studies are fused to different fluorophores such as enhanced green fluorescent protein (eGFP; donor molecule) and monomeric red fluorescent protein (mRFP; acceptor molecule). Energy transfer between the two fluorophore groups can only occur efficiently when the proteins of interest are in close physical proximity, around ≤10 nm, and therefore are most likely interacting. FRET-FLIM measures the decrease in excited-state lifetime of the donor fluorophore (eGFP) with and without the presence of the acceptor (mRFP) and can therefore give information on protein-protein interactions and the membrane topology of the tested protein. Here we describe the production of fluorescent protein fusions for FRET-FLIM analysis in tobacco leaf epidermal cells using Agrobacterium-mediated plant transformation and a FRET-FLIM data acquisition and analysis protocol in plant cells. These protocols are applicable and can be adapted for both membrane and soluble proteins in different cellular localizations. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Protein expression in tobacco leaf cells via transient Agrobacterium-mediated plant transformation Basic Protocol 2: FRET-FLIM data acquisition and analysis.
Collapse
Affiliation(s)
- Tatiana Spatola Rossi
- Endomembrane Structure and Function Research Group, Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Charlotte Pain
- Endomembrane Structure and Function Research Group, Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, UK
| | - Verena Kriechbaumer
- Endomembrane Structure and Function Research Group, Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| |
Collapse
|
9
|
Kriechbaumer V, Botchway SW. Methods for Detection of Protein Interactions with Plasmodesmata-Localized Reticulons. Methods Mol Biol 2022; 2457:209-218. [PMID: 35349142 DOI: 10.1007/978-1-0716-2132-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Plant reticulon family proteins (RTN) tubulate the ER by dimerization and oligomerization, creating localized ER membrane tensions that result in membrane curvature. Two RTN ER-shaping proteins have been found in the plasmodesmata (PD) proteome which could potentially contribute to the formation of the desmotubule, an ER-derived structure that crosses primary PD and physically connects the ER of two cells. Here we describe two methods used to identify partners of two PD-resident reticulon proteins, RTN3 and RTN6 that are located in primary PD at cytokinesis in tobacco (Nicotiana tabacum): immunoprecipitations using GFP-Trap®_A beads to find novel interaction partners and FRET-FLIM to test for and quantify direct protein-protein interactions in planta.
Collapse
Affiliation(s)
- Verena Kriechbaumer
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC), Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, UK
| |
Collapse
|
10
|
Mould RR, Botchway SW, Parkinson JRC, Thomas EL, Guy GW, Bell JD, Nunn AVW. Cannabidiol Modulates Mitochondrial Redox and Dynamics in MCF7 Cancer Cells: A Study Using Fluorescence Lifetime Imaging Microscopy of NAD(P)H. Front Mol Biosci 2021; 8:630107. [PMID: 34046425 PMCID: PMC8144465 DOI: 10.3389/fmolb.2021.630107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/16/2021] [Indexed: 12/23/2022] Open
Abstract
The cannabinoid, cannabidiol (CBD), is part of the plant's natural defense system that when given to animals has many useful medicinal properties, including activity against cancer cells, modulation of the immune system, and efficacy in epilepsy. Although there is no consensus on its precise mode of action as it affects many cellular targets, CBD does appear to influence mitochondrial function. This would suggest that there is a cross-kingdom ability to modulate stress resistance systems that enhance homeostasis. As NAD(P)H autofluorescence can be used as both a metabolic sensor and mitochondrial imaging modality, we assessed the potential of this technique to study the in vitro effects of CBD using 2-photon excitation and fluorescence lifetime imaging microscopy (2P-FLIM) of NAD(P)H against more traditional markers of mitochondrial morphology and cellular stress in MCF7 breast cancer cells. 2P-FLIM analysis revealed that the addition of CBD induced a dose-dependent decrease in bound NAD(P)H, with 20 µM treatments significantly decreased the contribution of bound NAD(P)H by 14.6% relative to the control (p < 0.001). CBD also increased mitochondrial concentrations of reactive oxygen species (ROS) (160 ± 53 vs. 97.6 ± 4.8%, 20 µM CBD vs. control, respectively, p < 0.001) and Ca2+ (187 ± 78 vs. 105 ± 10%, 20 µM CBD vs. the control, respectively, p < 0.001); this was associated with a significantly decreased mitochondrial branch length and increased fission. These are all suggestive of mitochondrial stress. Our results support the use of NAD(P)H autofluorescence as an investigative tool and provide further evidence that CBD can modulate mitochondrial function and morphology in a dose-dependent manner, with clear evidence of it inducing oxidative stress at higher concentrations. This continues to support emerging data in the literature and may provide further insight into its overall mode of action, not only in cancer, but potentially its function in the plant and why it can act as a medicine.
Collapse
Affiliation(s)
- Rhys Richard Mould
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Stanley W. Botchway
- Central Laser Facility, Science and Technology Facilities Council, UKRI, Rutherford Appleton Laboratory, Harwell Campus, Oxford, United Kingdom
| | - James R. C. Parkinson
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Elizabeth Louise Thomas
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | | | - Jimmy D. Bell
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Alistair V. W. Nunn
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| |
Collapse
|
11
|
Abstract
The need to describe and understand signaling pathways in live cell is seen as a primary route to identifying and developing targeted medicines. Signaling cascade is also seen as a complex communication and involves interactions between multiple interconnecting proteins. Where subcellularly and how different proteins interact need to be preserved during investigation. Furthermore, these complex events occurring simultaneously may lead to a single or multiple end point or cell function such as protein synthesis, cell cytoskeleton formation, DNA damage repair, or autophagy. There is therefore a need of real-time noninvasive methods for protein assays to enable direct visualization of the interactions in their natural environment and hence overcome the limitations of methods that rely on invasive cell disruption techniques. Förster resonance energy transfer (FRET) coupled with fluorescence lifetime imaging microscopy (FLIM) is an advanced imaging method to observe protein-protein interactions at nanometer scale inside single living cells in real-time. Here we describe the development and use of two-channel pulsed interleave excitation (PIE) for multiple protein interactions in the mTORC1 pathway. The proteins were first tagged with multiple color fluorescent protein derivatives. The FRET-FLIM combination means that the information gained from using standard steady-state FRET between interacting proteins is considerably improved by monitoring changes in the excited-state lifetime of the donor fluorophore where its quenching in the presence of the acceptor is evidence for a direct physical interaction.
Collapse
|
12
|
Bhartiya A, Robinson I, Yusuf M, Botchway SW. Combining Multicolor FISH with Fluorescence Lifetime Imaging for Chromosomal Identification and Chromosomal Sub Structure Investigation. Front Mol Biosci 2021; 8:631774. [PMID: 33816553 PMCID: PMC8010142 DOI: 10.3389/fmolb.2021.631774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 02/02/2021] [Indexed: 11/25/2022] Open
Abstract
Understanding the structure of chromatin in chromosomes during normal and diseased state of cells is still one of the key challenges in structural biology. Using DAPI staining alone together with Fluorescence lifetime imaging (FLIM), the environment of chromatin in chromosomes can be explored. Fluorescence lifetime can be used to probe the environment of a fluorophore such as energy transfer, pH and viscosity. Multicolor FISH (M-FISH) is a technique that allows individual chromosome identification, classification as well as assessment of the entire genome. Here we describe a combined approach using DAPI as a DNA environment sensor together with FLIM and M-FISH to understand the nanometer structure of all 46 chromosomes in the nucleus covering the entire human genome at the single cell level. Upon DAPI binding to DNA minor groove followed by fluorescence lifetime measurement and imaging by multiphoton excitation, structural differences in the chromosomes can be studied and observed. This manuscript provides a blow by blow account of the protocol required to perform M-FISH-FLIM of whole chromosomes.
Collapse
Affiliation(s)
- Archana Bhartiya
- London Centre for Nanotechnology, University College London, London, United Kingdom.,Research Complex at Harwell Rutherford Appleton Laboratory, Didcot, United Kingdom
| | - Ian Robinson
- London Centre for Nanotechnology, University College London, London, United Kingdom.,Condensed Matter Physics and Materials Science Division, Brookhaven National Lab, Upton, NY, United States
| | - Mohammed Yusuf
- London Centre for Nanotechnology, University College London, London, United Kingdom.,Research Complex at Harwell Rutherford Appleton Laboratory, Didcot, United Kingdom.,Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University, Karachi, Pakistan
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Oxon, United Kingdom
| |
Collapse
|
13
|
Botchway SW, Farooq S, Sajid A, Robinson IK, Yusuf M. Contribution of advanced fluorescence nano microscopy towards revealing mitotic chromosome structure. Chromosome Res 2021; 29:19-36. [PMID: 33686484 DOI: 10.1007/s10577-021-09654-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 01/07/2023]
Abstract
The organization of chromatin into higher-order structures and its condensation process represent one of the key challenges in structural biology. This is important for elucidating several disease states. To address this long-standing problem, development of advanced imaging methods has played an essential role in providing understanding into mitotic chromosome structure and compaction. Amongst these are two fast evolving fluorescence imaging technologies, specifically fluorescence lifetime imaging (FLIM) and super-resolution microscopy (SRM). FLIM in particular has been lacking in the application of chromosome research while SRM has been successfully applied although not widely. Both these techniques are capable of providing fluorescence imaging with nanometer information. SRM or "nanoscopy" is capable of generating images of DNA with less than 50 nm resolution while FLIM when coupled with energy transfer may provide less than 20 nm information. Here, we discuss the advantages and limitations of both methods followed by their contribution to mitotic chromosome studies. Furthermore, we highlight the future prospects of how advancements in new technologies can contribute in the field of chromosome science.
Collapse
Affiliation(s)
- S W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Oxford, UK
| | - S Farooq
- Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University, P.O.Box 3500, Karachi, 74800, Pakistan
| | - A Sajid
- Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University, P.O.Box 3500, Karachi, 74800, Pakistan
| | - I K Robinson
- London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK.,Brookhaven National Lab, Upton, NY, 11973, USA
| | - M Yusuf
- Centre for Regenerative Medicine and Stem Cell Research, Aga Khan University, P.O.Box 3500, Karachi, 74800, Pakistan. .,London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK.
| |
Collapse
|
14
|
Yang Y, Sun M, Yu Z, Liu J, Yan W, Liu Z, Wei M, Wang H. Designing high affinity target-binding peptides to HLA-E: a key membrane antigen of multiple myeloma. Aging (Albany NY) 2020; 12:20457-20470. [PMID: 33115963 PMCID: PMC7655190 DOI: 10.18632/aging.103858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/21/2020] [Indexed: 01/10/2023]
Abstract
Multiple myeloma (MM) is a plasma cell malignancy that is currently incurable. Finding new targets and designing drugs are crucial for the treatment of MM. The two datasets (GSE6691 and GSE39754) are used to screen highly expressed antigen on MM cells. HLA-E was an ideal target for it was a hub gene, and also located in one of the key clusters. Highly expression of HLA-E mRNA on MM cells was also confirmed by real-time qPCR testing the MM patients' samples in Shengjing hospital. Crystal structure of HLA-E was obtained from Protein Data Bank (PDB ID: 3CDG) which was used to design targeting peptides with Molecular Operating Environment software. By analyzing interaction between CD94/NKG2A and HLA-E, a peptide with twelve amino acids was screened as a model peptide. Peptides library was constructed by randomly replaced non-key amino acid. Peptide-protein docking method was used to identify high affinity peptides. PEPTIDE 1-3 and model peptide were synthesized and identified the affinity to HLA-E by flow cytometer and confocal laser microscopy. At last, PEPTIDE3 (NALDEYCEDKNR) was found with the highest affinity. Taking all, HLA-E is a new treatment target, and PEPTIDE 3 is an ideal high affinity target-binding peptide candidate.
Collapse
Affiliation(s)
- Ying Yang
- Department of Hematology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China
| | - Mingli Sun
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China
| | - Zhaojin Yu
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China
| | - Jinwei Liu
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China
- Department of Pharmacy, Chifeng Municipal Hospital, Chifeng Inner Mongolia, China
| | - Wei Yan
- Department of Hematology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Zhuogang Liu
- Department of Hematology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Minjie Wei
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China
| | - Hongtao Wang
- Department of Hematology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| |
Collapse
|
15
|
Blignaut M, Loos B, Botchway SW, Parker AW, Huisamen B. Ataxia-Telangiectasia Mutated is located in cardiac mitochondria and impacts oxidative phosphorylation. Sci Rep 2019; 9:4782. [PMID: 30886180 PMCID: PMC6423017 DOI: 10.1038/s41598-019-41108-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 02/26/2019] [Indexed: 01/16/2023] Open
Abstract
The absence of Ataxia-Telangiectasia mutated protein kinase (ATM) is associated with neurological, metabolic and cardiovascular defects. The protein has been associated with mitochondria and its absence results in mitochondrial dysfunction. Furthermore, it can be activated in the cytosol by mitochondrial oxidative stress and mediates a cellular anti-oxidant response through the pentose phosphate pathway (PPP). However, the precise location and function of ATM within mitochondria and its role in oxidative phosphorylation is still unknown. We show that ATM is found endogenously within cardiac myocyte mitochondria under normoxic conditions and is consistently associated with the inner mitochondrial membrane. Acute ex vivo inhibition of ATM protein kinase significantly decreased mitochondrial electron transfer chain complex I-mediated oxidative phosphorylation rate but did not decrease coupling efficiency or oxygen consumption rate during β-oxidation. Chemical inhibition of ATM in rat cardiomyoblast cells (H9c2) significantly decreased the excited-state autofluorescence lifetime of enzyme-bound reduced NADH and its phosphorylated form, NADPH (NAD(P)H; 2.77 ± 0.26 ns compared to 2.57 ± 0.14 ns in KU60019-treated cells). This suggests an interaction between ATM and the electron transfer chain in the mitochondria, and hence may have an important role in oxidative phosphorylation in terminally differentiated cells such as cardiomyocytes.
Collapse
Affiliation(s)
- Marguerite Blignaut
- Division of Medical Physiology, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, 7505, South Africa.
| | - Ben Loos
- Department of Physiological Sciences, Faculty of Sciences, Stellenbosch University, Stellenbosch, 7602, South Africa
| | - Stanley W Botchway
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
- Oxford Brookes University, Department of Biological and Medical Sciences, Oxford, OX3 0BP, UK
| | - Anthony W Parker
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
- Department of Physics, Faculty of Science, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - Barbara Huisamen
- Division of Medical Physiology, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, 7505, South Africa
- Biomedical, Research and Innovation Platform, South African Medical Research Council, Tygerberg, 7505, South Africa
| |
Collapse
|
16
|
Label-free imaging of neurotransmitters in live brain tissue by multi-photon ultraviolet microscopy. Neuronal Signal 2018; 2:NS20180132. [PMID: 32714595 PMCID: PMC7373235 DOI: 10.1042/ns20180132] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/20/2018] [Accepted: 10/29/2018] [Indexed: 12/20/2022] Open
Abstract
Visualizing small biomolecules in living cells remains a difficult challenge. Neurotransmitters provide one of the most frustrating examples of this difficulty, as our understanding of signaling in the brain critically depends on our ability to follow the neurotransmitter traffic. Last two decades have seen considerable progress in probing some of the neurotransmitters, e.g. by using false neurotransmitter mimics, chemical labeling techniques, or direct fluorescence imaging. Direct imaging harnesses the weak UV fluorescence of monoamines, which are some of the most important neurotransmitters controlling mood, memory, appetite, and learning. Here we describe the progress in imaging of these molecules using the least toxic direct excitation route found so far, namely multi-photon (MP) imaging. MP imaging of serotonin, and more recently that of dopamine, has allowed researchers to determine the location of the vesicles, follow their intracellular dynamics, probe their content, and monitor their release. Recent developments have even allowed ratiometric quantitation of the vesicular content. This review shows that MP ultraviolet (MP-UV) microscopy is an effective but underutilized method for imaging monoamine neurotransmitters in neurones and brain tissue.
Collapse
|
17
|
Kriechbaumer V, Maneta-Peyret L, Fouillen L, Botchway SW, Upson J, Hughes L, Richardson J, Kittelmann M, Moreau P, Hawes C. The odd one out: Arabidopsis reticulon 20 does not bend ER membranes but has a role in lipid regulation. Sci Rep 2018; 8:2310. [PMID: 29396477 PMCID: PMC5797236 DOI: 10.1038/s41598-018-20840-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 01/22/2018] [Indexed: 12/19/2022] Open
Abstract
Reticulons are integral ER membrane proteins characterised by a reticulon homology domain comprising four transmembrane domains which results in the proteins sitting in the membrane in a W-topology. Here we report on a novel subgroup of reticulons with an extended N-terminal domain and in particular on arabidopsis reticulon 20. Using high resolution confocal microscopy we show that reticulon 20 is located in a unique punctate pattern on the ER membrane. Its closest homologue reticulon 19 labels the whole ER. Other than demonstrated for the other members of the reticulon protein family RTN20 and 19 do not display ER constriction phenotypes on over expression. We show that mutants in RTN20 or RTN19, respectively, display a significant change in sterol composition in roots indicating a role in lipid regulation. A third homologue in this family -3BETAHSD/D1- is unexpectedly localised to ER exit sites resulting in an intriguing location difference for the three proteins.
Collapse
Affiliation(s)
- Verena Kriechbaumer
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom.
| | - Lilly Maneta-Peyret
- Laboratoire Biogenèse Membranaire, UMR 5200 CNRS-Université de Bordeaux, Villenave d'Ornon, France
| | - Laetitia Fouillen
- Laboratoire Biogenèse Membranaire, UMR 5200 CNRS-Université de Bordeaux, Villenave d'Ornon, France.,MetaboHub-Metabolome Facility of Bordeaux, Functional Genomics Center, Bordeaux, France
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, OX11 0QX, United Kingdom
| | - Jessica Upson
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom.,J.U.: The Sainsbury Laboratory, Norwich, United Kingdom
| | - Louise Hughes
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom
| | - Jake Richardson
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom
| | - Maike Kittelmann
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom
| | - Patrick Moreau
- Laboratoire Biogenèse Membranaire, UMR 5200 CNRS-Université de Bordeaux, Villenave d'Ornon, France
| | - Chris Hawes
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, United Kingdom
| |
Collapse
|
18
|
Abstract
Metabolons are protein complexes that contain all the enzymes necessary for a metabolic pathway but also scaffolding proteins. Such a structure allows efficient channeling of intermediate metabolites from one active site to the next and is highly advantageous for labile or toxic intermediates. Here we describe two methods currently used to identify metabolons via protein-protein interaction methodology: immunoprecipitations using GFP-Trap®_A beads to find novel interaction partners and potential metabolon components and FRET-FLIM to test for and quantify protein-protein interactions in planta.
Collapse
|
19
|
Estandarte AK, Botchway S, Lynch C, Yusuf M, Robinson I. The use of DAPI fluorescence lifetime imaging for investigating chromatin condensation in human chromosomes. Sci Rep 2016; 6:31417. [PMID: 27526631 PMCID: PMC4985626 DOI: 10.1038/srep31417] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 07/19/2016] [Indexed: 12/30/2022] Open
Abstract
Chromatin undergoes dramatic condensation and decondensation as cells transition between the different phases of the cell cycle. The organization of chromatin in chromosomes is still one of the key challenges in structural biology. Fluorescence lifetime imaging (FLIM), a technique which utilizes a fluorophore's fluorescence lifetime to probe changes in its environment, was used to investigate variations in chromatin compaction in fixed human chromosomes. Fixed human metaphase and interphase chromosomes were labeled with the DNA minor groove binder, DAPI, followed by measurement and imaging of the fluorescence lifetime using multiphoton excitation. DAPI lifetime variations in metaphase chromosome spreads allowed mapping of the differentially compacted regions of chromatin along the length of the chromosomes. The heteromorphic regions of chromosomes 1, 9, 15, 16, and Y, which consist of highly condensed constitutive heterochromatin, showed statistically significant shorter DAPI lifetime values than the rest of the chromosomes. Differences in the DAPI lifetimes for the heteromorphic regions suggest differences in the structures of these regions. DAPI lifetime variations across interphase nuclei showed variation in chromatin compaction in interphase and the formation of chromosome territories. The successful probing of differences in chromatin compaction suggests that FLIM has enormous potential for application in structural and diagnostic studies.
Collapse
Affiliation(s)
- Ana Katrina Estandarte
- London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Oxon, OX11 0FA, UK
| | - Stanley Botchway
- Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Oxon, OX11 0QX, UK
| | - Christophe Lynch
- London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Oxon, OX11 0FA, UK
| | - Mohammed Yusuf
- London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Oxon, OX11 0FA, UK
| | - Ian Robinson
- London Centre for Nanotechnology, University College London, London, WC1H 0AH, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Oxon, OX11 0FA, UK
| |
Collapse
|
20
|
Kriechbaumer V, Botchway SW, Hawes C. Localization and interactions between Arabidopsis auxin biosynthetic enzymes in the TAA/YUC-dependent pathway. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:4195-207. [PMID: 27208541 DOI: 10.1093/jxb/erw195] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The growth regulator auxin is involved in all key developmental processes in plants. A complex network of a multiplicity of potential biosynthetic pathways as well as transport, signalling plus conjugation and deconjugation lead to a complex and multifaceted system system for auxin function. This raises the question how such a system can be effectively organized and controlled. Here we report that a subset of auxin biosynthetic enzymes in the TAA/YUC route of auxin biosynthesis is localized to the endoplasmic reticulum (ER). ER microsomal fractions also contain a significant percentage of auxin biosynthetic activity. This could point toward a model of auxin function using ER membrane location and subcellular compartmentation for supplementary layers of regulation. Additionally we show specific protein-protein interactions between some of the enzymes in the TAA/YUC route of auxin biosynthesis.
Collapse
Affiliation(s)
- Verena Kriechbaumer
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Stanley W Botchway
- Central Laser Facility, Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot OX11 0QX, UK
| | - Chris Hawes
- Plant Cell Biology, Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| |
Collapse
|
21
|
Fitzgerald C, Hosny NA, Tong H, Seville PC, Gallimore PJ, Davidson NM, Athanasiadis A, Botchway SW, Ward AD, Kalberer M, Kuimova MK, Pope FD. Fluorescence lifetime imaging of optically levitated aerosol: a technique to quantitatively map the viscosity of suspended aerosol particles. Phys Chem Chem Phys 2016; 18:21710-9. [DOI: 10.1039/c6cp03674k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A technique to measure the viscosity of stably levitated single micron-sized aerosol particles.
Collapse
Affiliation(s)
- C. Fitzgerald
- Department of Chemistry
- University of Cambridge
- Cambridge
- UK
| | - N. A. Hosny
- Department of Chemistry
- Imperial College London
- London
- UK
| | - H. Tong
- Department of Chemistry
- University of Cambridge
- Cambridge
- UK
| | - P. C. Seville
- School of Pharmacy and Biomedical Sciences
- University of Central Lancashire
- Preston
- UK
| | | | - N. M. Davidson
- School of Geography
- Earth and Environmental Sciences
- University of Birmingham
- Birmingham
- UK
| | | | - S. W. Botchway
- The Science and Technology Facilities Council
- Rutherford Appleton Laboratory
- Research Complex at Harwell
- Oxfordshire
- UK
| | - A. D. Ward
- The Science and Technology Facilities Council
- Rutherford Appleton Laboratory
- Research Complex at Harwell
- Oxfordshire
- UK
| | - M. Kalberer
- Department of Chemistry
- University of Cambridge
- Cambridge
- UK
| | - M. K. Kuimova
- Department of Chemistry
- Imperial College London
- London
- UK
| | - F. D. Pope
- School of Geography
- Earth and Environmental Sciences
- University of Birmingham
- Birmingham
- UK
| |
Collapse
|
22
|
Botchway SW, Coulter JA, Currell FJ. Imaging intracellular and systemic in vivo gold nanoparticles to enhance radiotherapy. Br J Radiol 2015; 88:20150170. [PMID: 26118301 PMCID: PMC4730966 DOI: 10.1259/bjr.20150170] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Nanoparticles offer alternative options in cancer therapy both as drug delivery carriers and as direct therapeutic agents for cancer cell inactivation. More recently, gold nanoparticles (AuNPs) have emerged as promising radiosensitizers achieving significantly elevated radiation dose enhancement factors when irradiated with both kilo-electron-volt and mega-electron-volt X-rays. Use of AuNPs in radiobiology is now being intensely driven by the desire to achieve precise energy deposition in tumours. As a consequence, there is a growing demand for efficient and simple techniques for detection, imaging and characterization of AuNPs in both biological and tumour samples. Spatially accurate imaging on the nanoscale poses a serious challenge requiring high- or super-resolution imaging techniques. In this mini review, we discuss the challenges in using AuNPs as radiosensitizers as well as various current and novel imaging techniques designed to validate the uptake, distribution and localization in mammalian cells. In our own work, we have used multiphoton excited plasmon resonance imaging to map the AuNP intracellular distribution. The benefits and limitations of this approach will also be discussed in some detail. In some cases, the same “excitation” mechanism as is used in an imaging modality can be harnessed to make it also a part of therapy modality (e.g. phototherapy)—such examples are discussed in passing as extensions to the imaging modality concerned.
Collapse
Affiliation(s)
- S W Botchway
- 1 Science and Technology Facility Council, Research Complex at Harwell, CLF, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, UK
| | - J A Coulter
- 2 School of Pharmacy, McClay Research Centre, Queen's University Belfast, Belfast, UK
| | - F J Currell
- 3 School of Mathematics and Physics, Queens University Belfast, Belfast, UK
| |
Collapse
|