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Tang SW, Kwok SH, Li X, Tang KH, Kubi JA, Brah AS, Yeung K, Dong M, Lam YW. A new class of antimicrobial therapeutics targeting the envelope stress response of Gram-negative bacteria: abridged secondary publication. Hong Kong Med J 2023; 29 Suppl 4:39-44. [PMID: 37690807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023] Open
Affiliation(s)
- S W Tang
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - S H Kwok
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - X Li
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - K H Tang
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - J A Kubi
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong SAR, China
| | - A S Brah
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong SAR, China
| | - K Yeung
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong SAR, China
| | - M Dong
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Y W Lam
- School of Applied Science, University of Huddersfield, United Kingdom
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2
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Zhou C, Li X, Tang SW, Liu C, Lam MHW, Lam YW. A Dual-Enzyme Amplification Loop for the Sensitive Biosensing of Endopeptidases. ACS Omega 2023; 8:25592-25600. [PMID: 37483190 PMCID: PMC10357553 DOI: 10.1021/acsomega.3c03533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/23/2023] [Indexed: 07/25/2023]
Abstract
A rapid and sensitive approach for the detection of endopeptidases via a new analyte-triggered mutual emancipation of linker-immobilized enzymes (AMELIE) mechanism has been developed and demonstrated using a matrix metallopeptidase, a collagenase, as the model endopeptidase analyte. AMELIE involves an autocatalytic loop created by a pair of selected enzymes immobilized on solid substrates via linkers with specific sites that can be proteolyzed by one another. These bound enzymes are spatially separated so that they cannot act upon their corresponding substrates until the introduction of the target endopeptidase analyte that can also cleave one of the linkers. This triggers the self-sustained loop of enzymatic activities to emancipate all the immobilized enzymes. In this proof of concept, signal transduction was achieved by a colorimetric horseradish peroxidase-tetramethylbenzidine (HRP-TMB-H2O2) reaction with HRP that are also being immobilized by one of the linkers. The pair of immobilized enzymes were collagenase and alginate lyase, and they were immobilized by an alginate linker and a short peptide chain containing the amino acid sequence of Leu-Gly-Pro-Ala for collagenase. A detection limit of 2.5 pg collagenase mL-1 with a wide linear range up to 4 orders of magnitude was achieved. The AMELIE biosensor can detect extracellular collagenase in the supernatant of various bacteria cultures, with a sensitivity as low as 103 cfu mL-1 of E. coli. AMELIE can readily be adapted to provide the sensitive detection of other endopeptidases.
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Affiliation(s)
- Chuanwen Zhou
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Xiaomin Li
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Sze Wing Tang
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Chunxi Liu
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Michael H. W. Lam
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Yun Wah Lam
- Department
of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
- School
of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, U.K.
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3
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Shum J, Lee LCC, Chiang MWL, Lam YW, Lo KKW. A Concerted Enzymatic and Bioorthogonal Approach for Extracellular and Intracellular Activation of Environment-Sensitive Ruthenium(II)-Based Imaging Probes and Photosensitizers. Angew Chem Int Ed Engl 2023:e202303931. [PMID: 37191224 DOI: 10.1002/anie.202303931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 05/17/2023]
Abstract
In this article, we report a novel targeting strategy involving the combination of an enzyme-instructed self-assembly (EISA) moiety and a strained cycloalkyne to generate large accumulation of bioorthogonal sites in cancer cells. These bioorthogonal sites can serve as activation triggers in different regions for transition metal-based probes, which are new ruthenium(II) complexes carrying a tetrazine unit for controllable phosphorescence and singlet-oxygen generation. Importantly, the environment-sensitive emission of the complexes can be further enhanced in the hydrophobic regions offered by the large supramolecular assemblies, which is highly advantageous to biological imaging. Additionally, the (photo)cytotoxicity of the large supramolecular assemblies containing the complexes was investigated, and the results illustrate that cellular localization (extracellular and intracellular) imposes a profound impact on the efficiencies of photosensitizers.
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Affiliation(s)
- Justin Shum
- City University of Hong Kong, Department of Chemistry, HONG KONG
| | | | | | - Yun Wah Lam
- City University of Hong Kong, Department of Chemistry, HONG KONG
| | - Kenneth Kam-Wing Lo
- City University of Hong Kong, Department of Chemistry, Tat Chee Avenue, Kowloon Tong, N. A., Hong Kong, HONG KONG
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4
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Ilyas AO, Alam MK, Musah JD, Yang M, Lam YW, Roy VAL, Lau C. Investigation on the Direct and Bystander Effects in HeLa Cells Exposed to Very Low α-Radiation Using Electrical Impedance Measurement. ACS Omega 2021; 6:13995-14003. [PMID: 34124424 PMCID: PMC8190804 DOI: 10.1021/acsomega.0c05888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
The impact of radiation-induced bystander effect (RIBE) is still not well understood in radiotherapy. RIBEs are biological effects expressed by nonirradiated cells near or far from the irradiated cells. Most radiological studies on cancer cells have been based on biochemical characterization. However, biophysical investigation with label-free techniques to analyze and compare the direct irradiation effect and RIBE has lagged. In this work, we employed an electrical cell-indium tin oxide (ITO) substrate impedance system (ECIIS) as a bioimpedance sensor to evaluate the HeLa cells' response. The bioimpedance of untreated/nonirradiated HeLa (N-HeLa) cells, α-particle (Am-241)-irradiated HeLa (I-HeLa) cells, and bystander HeLa (B-HeLa) cells exposed to media from I-HeLa cells was monitored with a sampling interval of 8 s over a period of 24 h. Also, we imaged the cells at times where impedance changes were observed. Different radiation doses (0.5 cGy, 1.2 cGy, and 1.7 cGy) were used to investigate I-HeLa and B-HeLa cells' radiation-dose-dependence. By analyzing the changes in absolute impedance and cell size/number with time, compared to N-HeLa cells, B-HeLa cells mimicked the I-HeLa cells' damage and modification of proliferation rate. Contrary to the irradiated cells, the bystander cells' damage rate and proliferation rate enhancements have an inverse radiation-dose-response. Also, we report multiple RIBEs in HeLa cells in a single measurement and provide crucial insights into the RIBE mechanism without any labeling procedure. Unambiguously, our results have shown that the time-dependent control of RIBE is important during α-radiation-based radiotherapy of HeLa cells.
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Affiliation(s)
- AbdulMojeed O. Ilyas
- Department
of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong SAR, China
- Department
of Physics, Federal University Oye-Ekiti, Oye-Ekiti, Ekiti State 3600001, Nigeria
| | - Md Kowsar Alam
- Department
of Biomedical Sciences, City University
of Hong Kong, Kowloon 999077, Hong Kong SAR, China
- Department
of Physics, University of Chittagong, Chittagong 4331, Bangladesh
| | - Jamal-Deen Musah
- Department
of Material Science and Engineering and State Key Laboratory of Terahertz
and Millimeter Waves, City University of
Hong Kong, Kowloon 999077, Hong Kong SAR, China
| | - Mengsu Yang
- Department
of Biomedical Sciences, City University
of Hong Kong, Kowloon 999077, Hong Kong SAR, China
| | - Yun Wah Lam
- Department
of Chemistry, City University of Hong Kong, Kowloon 999077, Hong Kong SAR, China
| | - Vellaisamy A. L. Roy
- James
Watt School of Engineering, University of
Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Condon Lau
- Department
of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong SAR, China
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5
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Ilyas AM, Alam MK, Musah JD, Yang M, Roy VAL, Lam YW, Lau C. CHO cell dysfunction due to radiation-induced bystander signals observed by real-time electrical impedance measurement. Biosens Bioelectron 2021; 181:113142. [PMID: 33752028 DOI: 10.1016/j.bios.2021.113142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/22/2021] [Accepted: 03/01/2021] [Indexed: 11/30/2022]
Abstract
Radiation-induced bystander effects (RIBE) have raised many concerns about radiation safety and protection. In RIBE, unirradiated cells receive signals from irradiated cells and exhibit irradiation effects. Until now, most RIBE studies have been based on morphological and biochemical characterization. However, research on the impact of RIBE on biophysical properties of cells has been lagging. Non-invasive indium tin oxide (ITO)-based impedance systems have been used as bioimpedance sensors for monitoring cell behaviors. This powerful technique has not been applied to RIBE research. In this work, we employed an electrical cell-ITO substrate impedance system (ECIIS) to study the RIBE on Chinese hamster ovary (CHO) cells. The bioimpedance of bystander CHO cells (BCHO), alpha(α)-particle (Am-241) irradiated CHO (ICHO), and untreated/unirradiated CHO (UCHO) cells were monitored with a sampling interval of 8 s over a period of 24 h. Media from ICHO cells exposed to different radiation doses (0.3 nGy, 0.5 nGy, and 0.7 nGy) were used to investigate the radiation dose dependence of BCHO cells' impedance. In parallel, we imaged the cells at times where impedance changes were observed. By analyzing the changes in absolute impedance and cell size/cell number with time, we observed that BCHO cells mimicked ICHO cells in terms of modification in cell morphology and proliferation rate. Furthermore, these effects appeared to be time-dependent and inversely proportional to the radiation dose. Hence, this approach allows a label-free study of cellular responses to RIBE with high sensitivity and temporal resolution and can provide crucial insights into the RIBE mechanism.
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Affiliation(s)
- A M Ilyas
- Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong, China; Department of Physics, Federal University Oye-Ekiti, Ekiti State 3600001, Nigeria.
| | - Md Kowsar Alam
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon 999077, Hong Kong, China; Department of Physics, University of Chittagong, Chittagong 4331, Bangladesh
| | - Jamal-Deen Musah
- Department of Material Science and Engineering, State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Mengsu Yang
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Vellaisamy A L Roy
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong, China
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6
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Qiao W, Wong KHM, Shen J, Wang W, Wu J, Li J, Lin Z, Chen Z, Matinlinna JP, Zheng Y, Wu S, Liu X, Lai KP, Chen Z, Lam YW, Cheung KMC, Yeung KWK. TRPM7 kinase-mediated immunomodulation in macrophage plays a central role in magnesium ion-induced bone regeneration. Nat Commun 2021; 12:2885. [PMID: 34001887 PMCID: PMC8128914 DOI: 10.1038/s41467-021-23005-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 04/09/2021] [Indexed: 02/03/2023] Open
Abstract
Despite the widespread observations on the osteogenic effects of magnesium ion (Mg2+), the diverse roles of Mg2+ during bone healing have not been systematically dissected. Here, we reveal a previously unknown, biphasic mode of action of Mg2+ in bone repair. During the early inflammation phase, Mg2+ contributes to an upregulated expression of transient receptor potential cation channel member 7 (TRPM7), and a TRPM7-dependent influx of Mg2+ in the monocyte-macrophage lineage, resulting in the cleavage and nuclear accumulation of TRPM7-cleaved kinase fragments (M7CKs). This then triggers the phosphorylation of Histone H3 at serine 10, in a TRPM7-dependent manner at the promoters of inflammatory cytokines, leading to the formation of a pro-osteogenic immune microenvironment. In the later remodeling phase, however, the continued exposure of Mg2+ not only lead to the over-activation of NF-κB signaling in macrophages and increased number of osteoclastic-like cells but also decelerates bone maturation through the suppression of hydroxyapatite precipitation. Thus, the negative effects of Mg2+ on osteogenesis can override the initial pro-osteogenic benefits of Mg2+. Taken together, this study establishes a paradigm shift in the understanding of the diverse and multifaceted roles of Mg2+ in bone healing.
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Affiliation(s)
- Wei Qiao
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Dental Materials Science, Applied Oral Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR., China
| | - Karen H M Wong
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Jie Shen
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Wenhao Wang
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Jun Wu
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Jinhua Li
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Centre for Translational Bone, Joint and Soft Tissue Research, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Zhengjie Lin
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Zetao Chen
- Department of Oral Implantology, Hospital of Stomatology, Guanghua School of Stomatology, Institute of Stomatological Research, Sun Yat-sen University, Guangzhou, China
- Zhujiang New Town Clinic, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Jukka P Matinlinna
- Dental Materials Science, Applied Oral Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR., China
| | - Yufeng Zheng
- State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, China
| | - Shuilin Wu
- School of Materials Science and Engineering, Tianjin University, Tianjin, China
| | - Xuanyong Liu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China
| | - Keng Po Lai
- Guangxi Key Laboratory of Tumor Immunology and Microenvironmental Regulation, Guilin Medical University, Guilin, China
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
| | - Zhuofan Chen
- Zhujiang New Town Clinic, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China.
| | - Kenneth M C Cheung
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Kelvin W K Yeung
- Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
- Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China.
- China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou, China.
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Lai JCL, Leung MOY, Lee DYH, Lam YW, Berning K. Biomarking Trait Resilience With Salivary Cortisol in Chinese Undergraduates. Front Psychol 2020; 11:536510. [PMID: 33192778 PMCID: PMC7649282 DOI: 10.3389/fpsyg.2020.536510] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/22/2020] [Indexed: 12/19/2022] Open
Abstract
This study aimed to examine the relationship between trait resilience and salivary cortisol in a group of Chinese undergraduates. The Chinese versions of the Brief Resilience Scale and a measure of optimism, the revised Life Orientation Test were administered to 49 Chinese undergraduates who provided self-collected saliva samples six times per day (immediately after waking; 0.5, 3, 6, and 12 h thereafter; and at bedtime) over 3 consecutive weekdays. The cortisol data were aggregated across the 3 days to examine the association between resilience and components of the diurnal rhythm of cortisol using multiple regression. The results showed that higher resilience was associated with a stronger cortisol response to awakening and a steeper diurnal decline in cortisol from waking to bedtime. Resilience was positively associated with cortisol output over the course of the day but this relationship was not significant (p = 0.065). This pattern of diurnal rhythm is consistent with that typically observed in better adjusted individuals. Generated by an intensive protocol with compliance objectively monitored, these findings clearly indicate the important role of the hypothalamic-pituitary-adrenocortical axis in health and adjustment and contribute to the growing literature on resilience and cortisol in humans.
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Affiliation(s)
- Julian C L Lai
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Monique O Y Leung
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Daryl Y H Lee
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Karsten Berning
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
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Li Z, Lam YW, Liu Q, Lau AYK, Yu Au-Yeung H, Chan RHM. Machine Learning-Driven Drug Discovery: Prediction of Structure-Cytotoxicity Correlation Leads to Identification of Potential Anti-Leukemia Compounds. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2020:5464-5467. [PMID: 33019216 DOI: 10.1109/embc44109.2020.9175850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In vitro cytotoxicity screening is a crucial step of anticancer drug discovery. The application of deep learning methodology is gaining increasing attentions in processing drug screening data and studying anticancer mechanisms of chemical compounds. In this work, we explored the utilization of convolutional neural network in modeling the anticancer efficacy of small molecules. In particular, we presented a VGG19 model trained on 2D structural formulae to predict the growth-inhibitory effects of compounds against leukemia cell line CCRF-CEM, without any use of chemical descriptors. The model achieved a normalized RMSE of 15.76% on predicting growth inhibition and a Pearson Correlation Coefficient of 0.72 between predicted and experimental data, demonstrating a strong predictive power in this task. Furthermore, we implemented the Layer-wise Relevance Propagation technique to interpret the network and visualize the chemical groups predicted by the model that contribute to toxicity with human-readable representations.Clinical relevance-This work predicts the cytotoxicity of chemical compounds against human leukemic lymphoblast CCRF-CEM cell lines on a continuous scale, which only requires 2D images of the structural formulae of the compounds as inputs. Knowledge in the structure-toxicity relationship of small molecules will potentially increase the hit rate of primary drug screening assays.
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Tang SW, Tong WY, Pang SW, Voelcker NH, Lam YW. Deconstructing, Replicating, and Engineering Tissue Microenvironment for Stem Cell Differentiation. Tissue Eng Part B Rev 2020; 26:540-554. [PMID: 32242476 DOI: 10.1089/ten.teb.2020.0044] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
One of the most crucial components of regenerative medicine is the controlled differentiation of embryonic or adult stem cells into the desired cell lineage. Although most of the reported protocols of stem cell differentiation involve the use of soluble growth factors, it is increasingly evident that stem cells also undergo differentiation when cultured in the appropriate microenvironment. When cultured in decellularized tissues, for instance, stem cells can recapitulate the morphogenesis and functional specialization of differentiated cell types with speed and efficiency that often surpass the traditional growth factor-driven protocols. This suggests that the tissue microenvironment (TME) provides stem cells with a holistic "instructive niche" that harbors signals for cellular reprogramming. The translation of this into medical applications requires the decoding of these signals, but this has been hampered by the complexity of TME. This problem is often addressed by a reductionist approach, in which cells are exposed to substrates decorated with simple, empirically designed geometries, textures, and chemical compositions ("bottom-up" approach). Although these studies are invaluable in revealing the basic principles of mechanotransduction mechanisms, their physiological relevance is often uncertain. This review examines the recent progress of an alternative, "top-down" approach, in which the TME is treated as a holistic biological entity. This approach is made possible by recent advances in systems biology and fabrication technologies that enable the isolation, characterization, and reconstitution of TME. It is hoped that these new techniques will elucidate the nature of niche signals so that they can be extracted, replicated, and controlled. This review summarizes these emerging techniques and how the data they generated are changing our view on TME. Impact statement This review summarizes the current state of art of the understanding of instructive niche in the field of tissue microenvironment. Not only did we survey the use of different biochemical preparations as stimuli of stem cell differentiation and summarize the recent effort in dissecting the biochemical composition of these preparations, through the application of extracellular matrix (ECM) arrays and proteomics, but we also introduce the use of open-source, high-content immunohistochemistry projects in contributing to the understanding of tissue-specific composition of ECM. We believe this review would be highly useful for our peer researching in the same field. "Mr. Tulkinghorn is always the same… so oddly out of place and yet so perfectly at home." -Charles Dickens, Bleak House.
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Affiliation(s)
- Sze Wing Tang
- Department of Chemistry, City University of Hong Kong, Hong Kong, Hong Kong
| | - Wing Yin Tong
- Melbourne Center for Nanofabrication, Victorian Node of the Australian National Fabrication, Clayton, Australia.,Drug Delivery Disposition & Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Stella W Pang
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong, Hong Kong
| | - Nicolas H Voelcker
- Melbourne Center for Nanofabrication, Victorian Node of the Australian National Fabrication, Clayton, Australia.,Drug Delivery Disposition & Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Hong Kong, Hong Kong
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Abstract
The use of decellularized tissues or organs as cell culture scaffolds has proven to be a promising approach for tissue engineering and regenerative medicine, as these decellularized tissues can provide the instructive niche for cell differentiation and functions. Cartilage is a largely avascular tissue with limited regenerative capacity. Lesions caused by arthritis can lead to severe cartilage degeneration. Previous studies have indicated that decellularized cartilage can be used as scaffolds that support the chondrogenic differentiation of adult stem cells. However, these decellularization protocols all require the use of denaturing agents, such as high salt and detergents, that lead to the artifactual disruption of the chemical and physical integrity of the tissue microenvironment. Here, we established a new decellularization method for cartilage, through a combined effect of freezing-thawing, sectioning, and sonication in water. This protocol achieved the complete removal of cells within minutes, instead of hours or days required by existing procedures, and does not use any detergent. The resulting decellularized cartilage preserved the native ultrastructure and biochemical contents, including glycosaminoglycans, which is typically depleted by traditional decellularization methods. Human mesenchymal stem cells could readily adhere onto the decellularized cartilage. Together, this work unveils a simple new method for decellularizing cartilage, which will be useful in studying how tissue microenvironment supports chondrocyte growth and functions. Impact statement In this study, we develop a simple, fast cartilage decellularization method that does not require any detergent, so that the decellularized cartilage chemistry is preserved. Traditional detergent-based decellularization removes the tissue biochemical contents (i.e., glycosaminoglycans). In this new water decellularization protocol, the biochemical contents of cartilage can be preserved. This allows the study of biochemistry and physical content in extracellular matrix as a whole, and this protocol would definitely be useful for studying the effect of tissue microenvironment in supporting chondrocyte growth and functions.
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Affiliation(s)
- Wei Shen
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Karsten Berning
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Sze Wing Tang
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
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Xu S, Xie F, Tian L, Fallah S, Babaei F, Manno SHC, Manno FAM, Zhu L, Wong KF, Liang Y, Ramalingam R, Sun L, Wang X, Plumb R, Gethings L, Lam YW, Cheng SH. Estrogen accelerates heart regeneration by promoting the inflammatory response in zebrafish. J Endocrinol 2020; 245:39-51. [PMID: 31977314 PMCID: PMC7040496 DOI: 10.1530/joe-19-0413] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 01/24/2020] [Indexed: 12/27/2022]
Abstract
Sexual differences have been observed in the onset and prognosis of human cardiovascular diseases, but the underlying mechanisms are not clear. Here, we found that zebrafish heart regeneration is faster in females, can be accelerated by estrogen and is suppressed by the estrogen-antagonist tamoxifen. Injuries to the zebrafish heart, but not other tissues, increased plasma estrogen levels and the expression of estrogen receptors, especially esr2a. The resulting endocrine disruption induces the expression of the female-specific protein vitellogenin in male zebrafish. Transcriptomic analyses suggested heart injuries triggered pronounced immune and inflammatory responses in females. These responses, previously shown to elicit heart regeneration, could be enhanced by estrogen treatment in males and reduced by tamoxifen in females. Furthermore, a prior exposure to estrogen preconditioned the zebrafish heart for an accelerated regeneration. Altogether, this study reveals that heart regeneration is modulated by an estrogen-inducible inflammatory response to cardiac injury. These findings elucidate a previously unknown layer of control in zebrafish heart regeneration and provide a new model system for the study of sexual differences in human cardiac repair.
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Affiliation(s)
- Shisan Xu
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Fangjing Xie
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Li Tian
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Samane Fallah
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Fatemeh Babaei
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Sinai H C Manno
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Francis A M Manno
- School of Biomedical Engineering, Faculty of Engineering, University of Sydney, Sydney, New South Wales, Australia
| | - Lina Zhu
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Kin Fung Wong
- Department of Biomedical Engineering, Polytechnic University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Yimin Liang
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Rajkumar Ramalingam
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Lei Sun
- Department of Biomedical Engineering, Polytechnic University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Xin Wang
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Robert Plumb
- Waters Technologies Corporation, Milford, Massachusetts, USA
| | - Lee Gethings
- Waters Technologies Corporation, Milford, Massachusetts, USA
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
- Correspondence should be addressed to Y W Lam or S H Cheng: or
| | - Shuk Han Cheng
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
- State Key Laboratory of Marine Pollution (SKLMP) at City University of Hong Kong, Hong Kong SAR, People’s Republic of China
- Department of Materials Science and Engineering, College of Science and Engineering, City University of Hong Kong, Hong Kong SAR, People’s Republic of China
- Correspondence should be addressed to Y W Lam or S H Cheng: or
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12
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Tang SW, Yuen W, Kaur I, Pang SW, Voelcker NH, Lam YW. Capturing instructive cues of tissue microenvironment by silica bioreplication. Acta Biomater 2020; 102:114-126. [PMID: 31756551 DOI: 10.1016/j.actbio.2019.11.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 01/03/2023]
Abstract
Cells in tissues are enveloped by an instructive niche made of the extracellular matrix. These instructive niches contain three general types of information: topographical, biochemical and mechanical. While the combined effects of these three factors are widely studied, the functions of each individual one has not been systematically characterised, because it is impossible to alter a single factor in a tissue microenvironment without simultaneously affecting the other two. Silica BioReplication (SBR) is a process that converts biological samples into silica, faithfully preserving the original topography at the nano-scale. We explored the use of this technique to generate inorganic replicas of intact mammalian tissues, including tendon, cartilage, skeletal muscle and spinal cord. Scanning electron and atomic force microscopy showed that the resulting replicas accurately preserved the three-dimensional ultrastructure of each tissue, while all biochemical components were eradicated by calcination. Such properties allowed the uncoupling the topographical information of a tissue microenvironment from its biochemical and mechanical components. Here, we showed that human mesenchymal stem cells (MSC) cultured on the replicas of different tissues displayed vastly different morphology and focal adhesions, suggesting that the topography of the tissue microenvironment captured by SBR could profoundly affect MSC biology. MSC cultured on tendon replica elongated and expressed tenocytes marker, while MSC on the spinal cord replica developed into spheroids that resembled neurospheres, in morphology and in the expression of neurosphere markers, and could be further differentiated into neuron-like cells. This study reveals the significance of topographical cues in a cell niche, as tissue-specific topography was sufficient in initiating and directing differentiation of MSC, despite the absence of any biochemical signals. SBR is a convenient and versatile method for capturing this topographical information, facilitating the functional characterisation of cell niches. STATEMENT OF SIGNIFICANCE: Various studies have shown that three major factors, topographical, biochemical and mechanical, in a tissue microenvironment (TME) are essential for cellular homeostasis and functions. Current experimental models are too simplistic to represent the complexity of the TME, hindering the detailed understanding of its functions. In particular, the importance each factor in a tissue microenvironment have not been individually characterised, because it is challenging to alter one of these factors without simultaneously affecting the other two. Silica bioreplication (SBR) is a process that converts biological samples into silica replicas with high structural fidelity. SBR is a convenient and versatile method for capturing this topographical information on to a biologically inert material, allowing the functional characterisation of the architecture of a TME.
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Affiliation(s)
- Sze Wing Tang
- Department of Chemistry, City University of Hong Kong, Hong Kong
| | - Wai Yuen
- HealthBaby Biotech (Hong Kong) Co., Ltd, Hong Kong
| | - Ishdeep Kaur
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication, Australia; Monash Institute of Pharmaceutical Sciences, Monash University, Australia
| | - Stella W Pang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong
| | - Nicolas H Voelcker
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication, Australia; Monash Institute of Pharmaceutical Sciences, Monash University, Australia
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Hong Kong.
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13
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Yeo JH, Lam YW, Fraser ST. Cellular dynamics of mammalian red blood cell production in the erythroblastic island niche. Biophys Rev 2019; 11:873-894. [PMID: 31418139 PMCID: PMC6874942 DOI: 10.1007/s12551-019-00579-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022] Open
Abstract
Red blood cells, or erythrocytes, make up approximately a quarter of all cells in the human body with over 2 billion new erythrocytes made each day in a healthy adult human. This massive cellular production system is coupled with a set of cell biological processes unique to mammals, in particular, the elimination of all organelles, and the expulsion and destruction of the condensed erythroid nucleus. Erythrocytes from birds, reptiles, amphibians and fish possess nuclei, mitochondria and other organelles: erythrocytes from mammals lack all of these intracellular components. This review will focus on the dynamic changes that take place in developing erythroid cells that are interacting with specialized macrophages in multicellular clusters termed erythroblastic islands. Proerythroblasts enter the erythroblastic niche as large cells with active nuclei, mitochondria producing heme and energy, and attach to the central macrophage via a range of adhesion molecules. Proerythroblasts then mature into erythroblasts and, following enucleation, in reticulocytes. When reticulocytes exit the erythroblastic island, they are smaller cells, without nuclei and with few mitochondria, possess some polyribosomes and have a profoundly different surface molecule phenotype. Here, we will review, step-by-step, the biophysical mechanisms that regulate the remarkable process of erythropoiesis with a particular focus on the events taking place in the erythroblastic island niche. This is presented from the biological perspective to offer insight into the elements of red blood cell development in the erythroblastic island niche which could be further explored with biophysical modelling systems.
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Affiliation(s)
- Jia Hao Yeo
- Discipline of Anatomy and Histology, School of Medical Sciences, University of Sydney, Sydney, Australia.
- School of Chemistry, University of Sydney, Sydney, Australia.
- Discipline of Physiology, School of Medical Sciences, University of Sydney, Sydney, Australia.
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong
| | - Stuart T Fraser
- Discipline of Anatomy and Histology, School of Medical Sciences, University of Sydney, Sydney, Australia.
- Discipline of Physiology, School of Medical Sciences, University of Sydney, Sydney, Australia.
- Bosch Institute, School of Medical Sciences, University of Sydney, Sydney, Australia.
- University of Sydney Nano Institute, Sydney, Australia.
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14
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Lai JCL, Lee DYH, Leung MOY, Lam YW. Daily hassles, loneliness, and diurnal salivary cortisol in emerging adults. Horm Behav 2019; 115:104558. [PMID: 31310762 DOI: 10.1016/j.yhbeh.2019.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 06/29/2019] [Accepted: 07/12/2019] [Indexed: 11/21/2022]
Abstract
This study used an intensive protocol to examine the effects of daily hassles and loneliness on diurnal salivary cortisol levels. Fifty Chinese undergraduates (28 females) provided six saliva samples each day for two consecutive days (at 0, 0.5, 3, 6, and 12 h after waking and at bedtime) and completed a questionnaire that included scales to measure daily hassles experienced over the previous month, trait loneliness, and depression. Cortisol data were aggregated over two days and used in subsequent analyses, focusing on the cortisol awakening response, diurnal slope, and overall cortisol output operationalized as the area under the curve with reference to the ground (AUCG). Multiple regression analysis showed that an increase in loneliness had a significant association with an increase in the AUCG and with a steeper diurnal slope. Loneliness also showed a significant interaction with daily hassles in that the positive association between daily hassles and AUCG was accentuated in the participants who reported a greater degree of loneliness. Our findings demonstrate for the first time the importance of trait loneliness in modulating the association between daily hassles and diurnal cortisol levels, which has significant clinical implications. Interventions to reduce loneliness should help college students to better cope with daily stressors. Increased attention should also be paid to the health implications of an elevated cortisol level in this relatively young and healthy population.
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Affiliation(s)
- Julian C L Lai
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong.
| | - Daryl Y H Lee
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong; Division of Psychology and Language Sciences, University College London, United Kingdom
| | - Monique O Y Leung
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Hong Kong
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15
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Tang SW, Uddin MH, Tong WY, Pasic P, Yuen W, Thissen H, Lam YW, Voelcker NH. Replication of a Tissue Microenvironment by Thermal Scanning Probe Lithography. ACS Appl Mater Interfaces 2019; 11:18988-18994. [PMID: 31051073 DOI: 10.1021/acsami.9b05553] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Thermal scanning probe lithography (t-SPL) is a nanofabrication technique in which an immobilized thermolabile resist, such as polyphthalaldehyde (PPA), is locally vaporized by a heated atomic force microscope tip. Compared with other nanofabrication techniques, such as soft lithography and nanoimprinting lithography, t-SPL is more efficient and convenient as it does not involve time-consuming mask productions or complicated etching procedures, making it a promising candidate technique for the fast prototyping of nanoscale topographies for biological studies. Here, we established the direct use of PPA-coated surfaces as a cell culture substrate. We showed that PPA is biocompatible and that the deposition of allylamine by plasma polymerization on a silicon wafer before PPA coating can stabilize the immobilization of PPA in aqueous solutions. When seeded on PPA-coated surfaces, human mesenchymal stem cells (MSC) adhered, spread, and proliferated in a manner indistinguishable from cells cultured on glass surfaces. This allowed us to subsequently use t-SPL to generate nanotopographies for cell culture experiments. As a proof of concept, we analyzed the surface topography of bovine tendon sections, previously shown to induce morphogenesis and differentiation of MSC, by means of atomic force microscopy, and then "wrote" topographical data on PPA by means of t-SPL. The resulting substrate, matching the native tissue topography on the nanoscale, was directly used for MSC culture. The t-SPL substrate induced similar changes in cell morphology and focal adhesion formation in the MSC compared to native tendon sections, suggesting that t-SPL can rapidly generate cell culture substrates with complex and spatially accurate topographical signals. This technique may greatly accelerate the prototyping of models for the study of cell-matrix interactions.
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Affiliation(s)
- Sze Wing Tang
- Department of Chemistry , City University of Hong Kong , Tat Chee Avenue , Kowloon , Hong Kong SAR
| | - Md Hemayet Uddin
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility , 151 Wellington Road , Clayton , Victoria 3168 , Australia
| | - Wing Yin Tong
- Commonwealth Scientific and Industrial Research Organization (CSIRO) , Clayton , Victoria 3168 , Australia
| | - Paul Pasic
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility , 151 Wellington Road , Clayton , Victoria 3168 , Australia
| | - Wai Yuen
- HealthBaby Biotech (Hong Kong) Company, Limited , Lakeside 2 West Wing, No. 10 Science Park West Avenue , Sha Tin , Hong Kong SAR
| | - Helmut Thissen
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility , 151 Wellington Road , Clayton , Victoria 3168 , Australia
| | - Yun Wah Lam
- Department of Chemistry , City University of Hong Kong , Tat Chee Avenue , Kowloon , Hong Kong SAR
| | - Nicolas H Voelcker
- Drug Delivery Disposition & Dynamics, Monash Institute of Pharmaceutical Science , Monash University , 381 Royal Parade , Parkville , Victoria 3052 , Australia
- Commonwealth Scientific and Industrial Research Organization (CSIRO) , Clayton , Victoria 3168 , Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility , 151 Wellington Road , Clayton , Victoria 3168 , Australia
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16
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Tuwahatu CA, Yeung CC, Lam YW, Roy VAL. The molecularly imprinted polymer essentials: curation of anticancer, ophthalmic, and projected gene therapy drug delivery systems. J Control Release 2018; 287:24-34. [PMID: 30110614 DOI: 10.1016/j.jconrel.2018.08.023] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 08/10/2018] [Accepted: 08/11/2018] [Indexed: 02/06/2023]
Abstract
The development of polymeric materials as drug delivery systems has advanced from systems that rely on classical passive targeting to carriers that can sustain the precisely controlled release of payloads upon physicochemical triggers in desired microenvironment. Molecularly imprinted polymers (MIP), materials designed to capture specific molecules based on their molecular shape and charge distribution, are attractive candidates for fulfilling these purposes. In particular, drug-imprinted polymers coupled with active targeting mechanisms have been explored as potential drug delivery systems. In this review, we have curated important recent efforts in the development of drug-imprinted polymers in a variety of clinical applications, especially oncology and ophthalmology. MIP possesses properties that may complement the traditional delivery systems of these two disciplines, such as passive enhanced permeability and retention effect (EPR) in cancer tumors, and passive drug diffusion in delivering ophthalmic therapeutics. Furthermore, the prospects of MIP integration with the emerging gene therapies will be discussed.
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Affiliation(s)
- Christian Antonio Tuwahatu
- Department of Materials Science and Engineering and State Key Laboratory of Millimeter Waves, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Chi Chung Yeung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Vellaisamy Arul Lenus Roy
- Department of Materials Science and Engineering and State Key Laboratory of Millimeter Waves, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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17
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Lai JCL, Leung MOY, Lee DYH, Lam YW, Berning K. Loneliness and Diurnal Salivary Cortisol in Emerging Adults. Int J Mol Sci 2018; 19:ijms19071944. [PMID: 29970811 PMCID: PMC6073375 DOI: 10.3390/ijms19071944] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 06/11/2018] [Accepted: 07/02/2018] [Indexed: 11/16/2022] Open
Abstract
This study aimed to examine the relationship between trait loneliness and diurnal rhythms of salivary cortisol. Fifty-One Chinese undergraduates provided six saliva samples on a weekday at immediately, 0.5, 3, 6, and 12 h after waking, and at bedtime. Saliva collection times were monitored using electronic devices (MEMS TrackCaps). Participants were also administered a questionnaire consisting of scales measuring, trait loneliness, depression, and demographics. Relationships between loneliness and the cortisol awakening response (CAR), diurnal slope (DS), and area under the curve with respect to ground (AUCG) were examined using multiple regression analyses. Results showed that a higher loneliness score was associated with an attenuated CAR, a large AUCG, and a steeper DS, with the effects of compliance, waking time, and depression being controlled. As a blunted CAR and a higher diurnal cortisol level have been shown to be associated with poorer health in prior studies, increased attention to the mechanisms translating loneliness into disease endpoints via elevated cortisol is warranted.
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Affiliation(s)
- Julian Chuk Ling Lai
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong, China.
| | - Monique On Yee Leung
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong, China.
| | - Daryl Yu Heng Lee
- Psychophysiology Laboratory, Department of Social and Behavioural Sciences, City University of Hong Kong, Hong Kong, China.
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Hong Kong, China.
| | - Karsten Berning
- Department of Chemistry, City University of Hong Kong, Hong Kong, China.
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18
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Dong M, Seemann F, Humble JL, Liang Y, Peterson DR, Ye R, Ren H, Kim HS, Lee JS, Au DWT, Lam YW. Modification of the plasma complement protein profile by exogenous estrogens is indicative of a compromised immune competence in marine medaka (Oryzias melastigma). Fish Shellfish Immunol 2017; 70:260-269. [PMID: 28882797 DOI: 10.1016/j.fsi.2017.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/30/2017] [Accepted: 09/03/2017] [Indexed: 06/07/2023]
Abstract
Growing evidence suggests that the immune system of teleost is vulnerable to xenoestrogens, which are ubiquitous in the marine environment. This study detected and identified the major circulatory immune proteins deregulated by 17α-ethinylestradiol (EE2), which may be linked to fish susceptibility to pathogens in the marine medaka, Oryzias melastigma. Fish immune competence was determined using a host resistance assay to pathogenic bacteria Edwardsiella tarda. Females were consistently more susceptible to infection-induced mortality than males. Exposure to EE2 could narrow the sex gap of mortality by increasing infection-induced death in male fish. Proteomic analysis revealed that the major plasma immune proteins of adult fish were highly sexually dimorphic. EE2 induced pronounced sex-specific changes in the plasma proteome, with the male plasma composition clearly becoming "feminised". Male plasma was found to contain a higher level of fibrinogens, WAP63 and ependymin-2-like protein, which are involved in coagulation, inflammation and regeneration. For the first time, we demonstrated that expression of C1q subunit B (C1Q), an initiating factor of the classical complement pathway, was higher in males and was suppressed in both sexes in response to EE2 and bacterial challenge. Moreover, cleavage and post-translational modification of C3, the central component of the complement system, could be altered by EE2 treatment in males (C3dg down; C3g up). Multiple regression analysis indicated that C1Q is possibly an indicator of fish survival, which warrants further confirmation. The findings support the potential application of plasma immune proteins for prognosis/diagnosis of fish immune competence. Moreover, this study provides the first biochemical basis of the sex-differences in fish immunity and how these differences might be modified by xenoestrogens.
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Affiliation(s)
- Miao Dong
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Frauke Seemann
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Joseph L Humble
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Yimin Liang
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Drew R Peterson
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Rui Ye
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Honglin Ren
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Xi An Da Lu 5333, Changchun 130062, China
| | - Hui-Su Kim
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jae-Seong Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Doris W T Au
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
| | - Yun Wah Lam
- State Key Laboratory in Marine Pollution, Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
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19
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Tacoma R, Gelsinger SL, Lam YW, Scuderi RA, Ebenstein DB, Heinrichs AJ, Greenwood SL. Exploration of the bovine colostrum proteome and effects of heat treatment time on colostrum protein profile. J Dairy Sci 2017; 100:9392-9401. [PMID: 28918156 PMCID: PMC6350923 DOI: 10.3168/jds.2017-13211] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 07/24/2017] [Indexed: 01/28/2023]
Abstract
Heat treatment of colostrum is performed on modern dairy farms to reduce pathogenic contamination before hand-feeding the colostrum to newborn calves; however, limited data are available concerning effects of heat treatment on biologically active proteins in colostrum. The objective of this exploratory study was to investigate effects of heat treatment and length of heat treatment on colostrum protein profile. Colostrum samples were collected from Holstein cows within 12 h after parturition and assigned to the following groups: heat treatment at 60°C for 0 (untreated control), 30, 60, or 90 min. Samples were fractionated using acid precipitation, followed by ultracentrifugation and ProteoMiner (Bio-Rad Laboratories, Hercules, CA) treatment, and tandem-mass tagging was used to comparatively assess the low abundance protein profile. A total of 162 proteins were identified with more than 2 peptides in the low abundance protein enriched fraction. Of these, 62 differed in abundance by more than 2-fold in heat treated samples compared with the unheated control. The majority of proteins affected by heat treatment were involved in immunity, enzyme function, and transport-related processes; affected proteins included lactadherin, chitinase-3-like protein 1, and complement component C9. These results provide a foundation for further research to determine optimum heat treatment practices to ensure newborn calves are fed colostrum-containing proteins with the highest nutritional and biological value.
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Affiliation(s)
- R Tacoma
- Department of Animal and Veterinary Sciences, The University of Vermont, Burlington 05405
| | - S L Gelsinger
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - Y W Lam
- Vermont Genetics Network Proteomics Facility, The University of Vermont, Burlington 05405
| | - R A Scuderi
- Department of Animal and Veterinary Sciences, The University of Vermont, Burlington 05405
| | - D B Ebenstein
- Department of Animal and Veterinary Sciences, The University of Vermont, Burlington 05405
| | - A J Heinrichs
- Department of Animal Science, The Pennsylvania State University, University Park 16802.
| | - S L Greenwood
- Department of Animal and Veterinary Sciences, The University of Vermont, Burlington 05405
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Zhou SF, Gopalakrishnan S, Xu YH, To SKY, Wong AST, Pang SW, Lam YW. Substrates with patterned topography reveal metastasis of human cancer cells. Biomed Mater 2017; 12:055001. [DOI: 10.1088/1748-605x/aa785d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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21
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Xu Y, Zhou S, Lam YW, Pang SW. Dynamics of Natural Killer Cells Cytotoxicity in Microwell Arrays with Connecting Channels. Front Immunol 2017; 8:998. [PMID: 28861090 PMCID: PMC5562680 DOI: 10.3389/fimmu.2017.00998] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 08/04/2017] [Indexed: 01/22/2023] Open
Abstract
Natural killer (NK) cells serve an important role in immune system by recognizing and killing the potentially malignant cells without antigen sensitization, and could be promising in cancer therapy. We have designed and fabricated microwell arrays with microchannel connections in polydimethylsiloxane (PDMS) substrates to study the interaction dynamics of NK-92MI cells with MCF7 breast cancer cells using time-lapse imaging by fluorescence microscopy for 15 h. Although cell seeding density was the same, NK cell cytotoxicity was found to be higher in larger microwells, which is manifested as increased target death ratio from 13.7 ± 3.1 to 46.3 ± 3.3% and shorter triggering time of first target lysis from 502 ± 49 to 391 ± 63 min in 150 μm × 150 μm microwells comparing to 50 μm × 50 μm wells in 15 h. Mirochannel connection between adjacent microwells of the same size increased the overall target death ratio by >10%, while connection between microwells of different sizes led to significantly increased target death ratio and delayed first target lysis in smaller microwells. Our findings reveal unique cell interaction dynamics, such as initiation and stimulation, of NK cell cytotoxicity in a confined microenvironment, which is different from population-based study, and the results could lead to a better understanding of the dynamics of NK cell cytotoxicity.
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Affiliation(s)
- Yuanhao Xu
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Shufan Zhou
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Yun Wah Lam
- Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong.,Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Stella W Pang
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
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22
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Dong M, Liang Y, Ramalingam R, Tang SW, Shen W, Ye R, Gopalakrishnan S, Au DWT, Lam YW. Proteomic characterization of the interactions between fish serum proteins and waterborne bacteria reveals the suppression of anti-oxidative defense as a serum-mediated antimicrobial mechanism. Fish Shellfish Immunol 2017; 62:96-106. [PMID: 28089893 DOI: 10.1016/j.fsi.2017.01.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 01/06/2017] [Accepted: 01/07/2017] [Indexed: 06/06/2023]
Abstract
Fish blood is one of the crucial tissues of innate immune system, but the full repertoire of fish serum components involved in antibacterial defense is not fully identified. In this study, we demonstrated that turbot serum, but not the heat-inactivated control, significantly reduced the number of Edwardsiella tarda (E. tarda). By conjugating serum proteins with fluorescent dyes, we showed that E. tarda were coated with multiple fish proteins. In order to identify these proteins, we used E. tarda to capture turbot serum proteins and subjected the samples to shotgun proteomic analysis. A total of 76 fish proteins were identified in high confidence, including known antimicrobial proteins such as immunoglobins and complement components. 34 proteins with no previously known immunological functions were also identified. The expression of one of these proteins, IQ motif containing H (IQCH), was exclusively in fish brain and gonads and was induced during bacterial infection. This approach also allowed the study of the corresponding proteomic changes in E. tarda exposed to turbot serum, which is a general decrease of bacterial protein expression except for an upregulation of membrane components after serum treatment. Interestingly, while most other known stresses stimulate bacterial antioxidant enzymes, fish serum induced a rapid suppression of antioxidant proteins and led to an accumulation of reactive oxygen species. Heat treatment of fish serum eliminated this effect, suggesting that heat labile factors in the fish serum overrode bacterial antioxidant defenses. Taken together, this work offers a comprehensive view of the interactions between fish serum proteins and bacteria, and reveals previously unknown factors and mechanisms in fish innate immunity.
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Affiliation(s)
- Miao Dong
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Yimin Liang
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Rajkumar Ramalingam
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Sze Wing Tang
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Wei Shen
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Rui Ye
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Singaram Gopalakrishnan
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Doris Wai Ting Au
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
| | - Yun Wah Lam
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
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23
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Dong M, Lei H, Humble JL, Liang Y, Shen W, Au DW, Sun H, Lam YW. Collection and characterization of potentially novel antimicrobial peptides from Japanese medaka plasma. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.76.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
The excessive use of antibiotics in aquaculture contributes to the uprising of antibiotic resistance that threatens human health. We explore the innate immunity of fish for naturally occurring antimicrobial factors that can be developed into potential antibiotic agents. Antimicrobial peptides (AMPs) have been studied in many organisms but efforts on the systematic identification of AMPs in fish have been lacking. In this study, we systematically identified naturally occurring peptides in medaka plasma. Blood collected from medaka of different gender, age and infection status were combined. Peptides under the molecular weight of 3kDa were fractionated and purified, followed by mass spectrometry analysis. In total, 6483 unique peptides were identified against the medaka genome, constituting a database of circulating peptides in this organism. After evaluation with a combination of web-based prediction tool and conserved physicochemical properties of AMPs, 83 potential antimicrobial peptides were predicted. One of them, a 13-residue peptide named VPS13D3241–3253, showed a broad-spectrum toxicity on fish and human pathogenic bacteria (gram+ or gram−) without significant cytotoxicity on mammalian cell lines. Scanning electron microscopy indicated that VPS13D3241–3253 disrupted the cell wall of both gram+ and gram− bacteria. SOS response assay showed that this peptide efficiently induced DNA damage in bacteria. The identification of VPS13D3241–3253 illustrates the feasibility of the proteomic approach in the discovery of potentially novel AMPs from fish. These AMPs will form an important basis for the development of new antibacterial agents in the fish farming industries.
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Affiliation(s)
| | | | | | | | - Wei Shen
- 1City Univ. of Hong Kong, Hong Kong
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24
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Dong M, Tang SW, Shen W, Au DW, Lam YW. Characterization of the interactions between fish serum proteins and pathogenic bacteria by using label-free quantitative proteomics. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.63.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Fish blood is a valuable source of antimicrobial proteins which form a crucial part of the innate immune system, but the types and functions of these proteins are still not fully understood. The objectives of this study are to systematically characterize the serum proteins from fish that stably bind to bacteria and to investigate how bacteria respond to these interactions. Serum from turbot, but not the heat-inactivated control, significantly decreased the number of E. tarda bacteria. By conjugating fish serum proteins with fluorescent dye, we showed that E.tarda were coated with multiple labeled proteins. In order to systematically identify these bacteria-binding proteins, we used E.tarda cells to capture turbot serum proteins and subjected the samples to shotgun proteomic analysis, followed by label-free quantitation. A total of 76 fish proteins have been identified, including known antimicrobial proteins such as complement components and Wap65-2. 34 proteins with no previously known immunological function were also identified to bind to E.tarda. This approach also allowed the study of the proteomic changes in E.tarda exposed to turbot serum. Our data indicated a rapid decrease of translation factors and an upregulation of membrane components in response to serum treatment. Interestingly, fish serum induced a rapid suppression of the expression of bacterial antioxidant enzymes like catalase and led to an accumulation of reactive oxygen species, suggesting that fish serum can override a bacterial self-defence mechanism. Taken together, this work offers a comprehensive view of the interactions between fish serum proteins and pathogenic bacteria, and reveals previously unknown factors and mechanisms in fish innate immunity.
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Affiliation(s)
| | | | - Wei Shen
- 1City Univ. of Hong Kong, Hong Kong
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25
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Babaei F, Hong TLC, Yeung K, Cheng SH, Lam YW. Contrast-Enhanced X-Ray Micro-Computed Tomography as a Versatile Method for Anatomical Studies of Adult Zebrafish. Zebrafish 2016; 13:310-6. [PMID: 27058023 DOI: 10.1089/zeb.2016.1245] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
One attractive quality of zebrafish as a model organism for biological research is that transparency at early developmental stages allows the optical imaging of cellular and molecular events. However, this advantage cannot be applied to adult zebrafish. In this study, we explored the use of contrast-enhanced X-ray micro-computed tomography (microCT) on adult zebrafish in which the organism was stained with iodine, a simple and economical contrasting agent, after fixation. Tomographic reconstruction of the microCT data allowed the three-dimensional (3D) volumetric analyses of individual organs in adult zebrafish. Adipose tissues showed a higher affinity to iodine and were more strongly contrasted in microCT. As traditional histological techniques often involve dehydration steps that remove tissue lipids, iodine-contrasted microCT offers a convenient method for visualizing fat deposition in fish. Utilizing this advantage, we discovered a transient accumulation of lipids around the heart after ventricular amputation, suggesting a correlation between lipid distribution and heart regeneration. Taken together, microCT is a versatile technique that enables the 3D visualization of zebrafish organs, as well as other fish models, in their anatomical context. This simple method is a valuable new addition to the arsenal of techniques available to this model organism.
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Affiliation(s)
- Fatemeh Babaei
- 1 Department of Biology and Chemistry, City University of Hong Kong , Hong Kong SAR, China .,2 Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Tony Liu Chi Hong
- 3 Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong , Hong Kong SAR, China
| | - Kelvin Yeung
- 3 Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong , Hong Kong SAR, China
| | - Shuk Han Cheng
- 2 Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Yun Wah Lam
- 1 Department of Biology and Chemistry, City University of Hong Kong , Hong Kong SAR, China
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26
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Zhou SF, Gopalakrishnan S, Xu YH, Yang J, Lam YW, Pang SW. A Unidirectional Cell Switching Gate by Engineering Grating Length and Bending Angle. PLoS One 2016; 11:e0147801. [PMID: 26821058 PMCID: PMC4731054 DOI: 10.1371/journal.pone.0147801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/09/2016] [Indexed: 11/18/2022] Open
Abstract
On a microgrooved substrate, cells migrate along the pattern, and at random positions, reverse their directions. Here, we demonstrate that these reversals can be controlled by introducing discontinuities to the pattern. On "V-shaped grating patterns", mouse osteogenic progenitor MC3T3-E1 cells reversed predominately at the bends and the ends. The patterns were engineered in a way that the combined effects of angle- and length-dependence could be examined in addition to their individual effects. Results show that when the bend was placed closer to one end, migration behaviour of cells depends on their direction of approach. At an obtuse bend (135°), more cells reversed when approaching from the long segment than from the short segment. But at an acute bend (45°), this relationship was reversed. Based on this anisotropic behaviour, the designed patterns effectively allowed cells to move in one direction but blocked migrations in the opposing direction. This study demonstrates that by the strategic placement of bends and ends on grating patterns, we can engineer effective unidirectional switching gates that can control the movement of adherent cells. The knowledge developed in this study could be utilised in future cell sorting or filtering platforms without the need for chemotaxis or microfluidic control.
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Affiliation(s)
- Shu Fan Zhou
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Singaram Gopalakrishnan
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yuan Hao Xu
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Jie Yang
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yun Wah Lam
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Stella W Pang
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
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27
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Abstract
The nucleolus is a non-membrane-bound nuclear organelle found in all eukaryotes. It is the quintessential ‘RNA-seeded’ nuclear body, forming around specific chromosomal features called nucleolar organizing regions that contain arrays of ribosomal DNA. Assembly is triggered by activation of RNA polymerase I-mediated transcription and regulated in mammalian cells in a cell cycle-dependent manner. Although the nucleolus is best known for its role in coordinating ribosome biogenesis, biochemical and proteomic analyses have revealed a much wider functional complexity than previously appreciated, including roles in cell cycle regulation, DNA damage sensing and repair, pre-mRNA processing, telomere metabolism, processing of non-coding RNAs, and coordination of the cellular response to various stresses. Despite these advances, much remains to be learned about the full range of biological processes that occur within, or involve, this organelle and how its assembly/disassembly and functional reorganization in response to various stimuli are regulated. Here, we review the impact of recent studies that provide major insights into these fundamental questions, and we highlight the therapeutic potential of targeting nucleolar pathways.
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Affiliation(s)
- Yun Wah Lam
- Department of Biology and Chemistry, City University of Hong KongTat Chee Avenue, KowloonHong Kong
| | - Laura Trinkle-Mulcahy
- Department of Cellular & Molecular Medicine and Ottawa Institute of Systems Biology, University of Ottawa451 Smyth Road, Ottawa, ON, K1H 8M5Canada
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28
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Poon E, Keung W, Liang Y, Ramalingam R, Yan B, Zhang S, Chopra A, Moore J, Herren A, Lieu DK, Wong HS, Weng Z, Wong OT, Lam YW, Tomaselli GF, Chen C, Boheler KR, Li RA. Proteomic Analysis of Human Pluripotent Stem Cell-Derived, Fetal, and Adult Ventricular Cardiomyocytes Reveals Pathways Crucial for Cardiac Metabolism and Maturation. ACTA ACUST UNITED AC 2015; 8:427-36. [PMID: 25759434 DOI: 10.1161/circgenetics.114.000918] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 02/18/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Differentiation of pluripotent human embryonic stem cells (hESCs) to the cardiac lineage represents a potentially unlimited source of ventricular cardiomyocytes (VCMs), but hESC-VCMs are developmentally immature. Previous attempts to profile hESC-VCMs primarily relied on transcriptomic approaches, but the global proteome has not been examined. Furthermore, most hESC-CM studies focus on pathways important for cardiac differentiation, rather than regulatory mechanisms for CM maturation. We hypothesized that gene products and pathways crucial for maturation can be identified by comparing the proteomes of hESCs, hESC-derived VCMs, human fetal and human adult ventricular and atrial CMs. METHODS AND RESULTS Using two-dimensional-differential-in-gel electrophoresis, 121 differentially expressed (>1.5-fold; P<0.05) proteins were detected. The data set implicated a role of the peroxisome proliferator-activated receptor α signaling in cardiac maturation. Consistently, WY-14643, a peroxisome proliferator-activated receptor α agonist, increased fatty oxidative enzyme level, hyperpolarized mitochondrial membrane potential and induced a more organized morphology. Along this line, treatment with the thyroid hormone triiodothyronine increased the dynamic tension developed in engineered human ventricular cardiac microtissue by 3-fold, signifying their maturation. CONCLUSIONS We conclude that the peroxisome proliferator-activated receptor α and thyroid hormone pathways modulate the metabolism and maturation of hESC-VCMs and their engineered tissue constructs. These results may lead to mechanism-based methods for deriving mature chamber-specific CMs.
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Affiliation(s)
- Ellen Poon
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Wendy Keung
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Yimin Liang
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Rajkumar Ramalingam
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Bin Yan
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Shaohong Zhang
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Anant Chopra
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Jennifer Moore
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Anthony Herren
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Deborah K Lieu
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Hau San Wong
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Zhihui Weng
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - On Tik Wong
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Yun Wah Lam
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Gordon F Tomaselli
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Christopher Chen
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Kenneth R Boheler
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.)
| | - Ronald A Li
- From the Stem Cell and Regenerative Medicine Consortium (E.P., W.K., B.Y., Z.W., O.T. W., K.R.B., R.A.L.) and Department of Physiology, LKS Faculty of Medicine (E.P., W.K., B.Y., Z.W., O.T.W., K.R.B., R.A.L.), University of Hong Kong, Hong Kong, P.R. China; Departments of Biology and Chemistry (Y.M.L., R.R., Y.W.L.) and Computer Science (H.S.W.), City University of Hong Kong, Hong Kong, P.R. China; Department of Computer Science, Guangzhou University, Guangzhou, P.R. China (S.Z.); Department of Bioengineering, Boston University, MA (A.C., C.C.); Harvard Wyss Institute for Biologically Inspired Engineering, Boston, MA (A.C., C.C.); Department of Cell Biology and Human Anatomy, University of California, Davis (J.M., A.H., D.K.L.); Cardiovascular Research Center, Mount Sinai School of Medicine, New York (D.K.L., R.A.L.); and Division of Cardiology, Johns Hopkins University, Baltimore, MD (G.F.T., K.R.B.).
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Abstract
The nucleolus was one of the first subcellular organelles to be isolated from the cell. The advent of modern proteomic techniques has resulted in the identification of thousands of proteins in this organelle, and live cell imaging technology has allowed the study of the dynamics of these proteins. However, the limitations of current nucleolar isolation methods hinder the further exploration of this structure. In particular, these methods require the use of a large number of cells and tedious procedures. In this chapter we describe a new and improved nucleolar isolation method for cultured adherent cells. In this method cells are snap-frozen before direct sonication and centrifugation onto a sucrose cushion. The nucleoli can be obtained within a time as short as 20 min, and the high yield allows the use of less starting material. As a result, this method can capture rapid biochemical changes in nucleoli by freezing the cells at a precise time, hence faithfully reflecting the protein composition of nucleoli at the specified time point. This protocol will be useful for proteomic studies of dynamic events in the nucleolus and for better understanding of the biology of mammalian cells.
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Affiliation(s)
- Zhou Fang Li
- Department of Biology, South University of Science and Technology of China, 1088 Xueyuan Blvd., Nanshan, Shenzhen, Guangdong, P.R. China,
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Tang QY, Qian WX, Xu YH, Gopalakrishnan S, Wang JQ, Lam YW, Pang SW. Control of cell migration direction by inducing cell shape asymmetry with patterned topography. J Biomed Mater Res A 2014; 103:2383-93. [PMID: 25430523 DOI: 10.1002/jbm.a.35378] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 11/11/2014] [Accepted: 11/20/2014] [Indexed: 01/23/2023]
Abstract
In this study, we explored the concept of introducing asymmetry to cell shapes by patterned cell culture substrates, and investigated the consequence of this induced asymmetry to cell migration behaviors. Three patterns, named "Squares", "Grating", and "Arcs" were fabricated, representing different levels of rotational asymmetry. Using time-lapse imaging, we systematically compared the motility and directionality of mouse osteoblastic cells MC3T3-E1 cultured on these patterns. Cells were found to move progressively faster on "Arcs" than on "Grating", and cells on "Squares" were the slowest, suggesting that cell motility correlates with the level of rotational asymmetry of the repeating units of the pattern. Among these three patterns, on the "Arcs" pattern, the least symmetrical one, cells not only moved with the highest velocity but also the strongest directional persistence. Although this enhanced motility was not associated with the detected number of focal adhesion sites in the cells, the pattern asymmetry was reflected in the asymmetrical cell spreading. Cells on the "Arcs" pattern consistently displayed larger cytoplasmic protrusion on one side of the cell. This asymmetry in cell shape determined the direction and speed of cell migration. These observations suggest that topographical patterns that enhance the imbalance between the leading and trailing fronts of adherent cells will increase cell speed and control movement directions. Our discovery shows that complex cell behaviors such as the direction of cell movement are influenced by simple geometrical principles, which can be utilized as the design foundation for platforms that guide and sort cultured cells.
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Affiliation(s)
- Q Y Tang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - W X Qian
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,School of Electronic and Optical Engineering, Nanjing University of Science and Technology, China
| | - Y H Xu
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - S Gopalakrishnan
- Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - J Q Wang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,College of Electronic Science and Technology, Dalian University of Technology, China
| | - Y W Lam
- Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - S W Pang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
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Kwan KH, Yeung KW, Liu X, Wong KK, Shum HC, Lam YW, Cheng SH, Cheung KM, To MK. Silver nanoparticles alter proteoglycan expression in the promotion of tendon repair. Nanomedicine: Nanotechnology, Biology and Medicine 2014; 10:1375-83. [DOI: 10.1016/j.nano.2013.11.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 11/03/2013] [Accepted: 11/29/2013] [Indexed: 11/15/2022]
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Lim H, Utyuzhnikov SV, Lam YW, Kelly L. Potential-based methodology for active sound control in three dimensional settings. J Acoust Soc Am 2014; 136:1101. [PMID: 25190385 DOI: 10.1121/1.4892934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This paper extends a potential-based approach to active noise shielding with preservation of wanted sound in three-dimensional settings. The approach, which was described in a previous publication [Lim et al., J. Acoust. Soc. Am. 129(2), 717-725 (2011)], provides several significant advantages over conventional noise control methods. Most significantly, the methodology does not require any information including the characterization of sources, impedance boundary conditions and surrounding medium, and that the methodology automatically differentiates between the wanted and unwanted sound components. The previous publication proved the concept in one-dimensional conditions. In this paper, the approach for more realistic conditions is studied by numerical simulation and experimental validation in three-dimensional cases. The results provide a guideline to the implementation of the active shielding method with practical three-dimensional conditions. Through numerical simulation it is demonstrated that while leaving the wanted sound unchanged, the developed approach offers selective volumetric noise cancellation within a targeted domain. In addition, the method is implemented in a three-dimensional experiment with a white noise source in a semi-anechoic chamber. The experimental study identifies practical difficulties and limitations in the use of the approach for real applications.
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Affiliation(s)
- H Lim
- I-Lab, Centre for Vision, Speech, and Signal Processing, University of Surrey, Guilford, Surrey GU2 7XH, United Kingdom
| | - S V Utyuzhnikov
- School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Y W Lam
- Acoustics Research Centre, University of Salford, Salford, Greater Manchester, M5 4WT, United Kingdom
| | - L Kelly
- Acoustics Research Centre, University of Salford, Salford, Greater Manchester, M5 4WT, United Kingdom
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Tang SW, Tong WY, Shen W, Yeung KWK, Lam YW. Stringent requirement for spatial arrangement of extracellular matrix in supporting cell morphogenesis and differentiation. BMC Cell Biol 2014; 15:10. [PMID: 24661496 PMCID: PMC3987840 DOI: 10.1186/1471-2121-15-10] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 03/19/2014] [Indexed: 01/30/2023] Open
Abstract
Background In vitro experiments on the functional roles of extracellular matrix (ECM) components usually involve the culture of cells on surfaces coated with purified ECM components. These experiments can seldom recuperate the spatial arrangement of ECM found in vivo. In this study, we have overcome this obstacle by using histological sections of bovine Achilles tendon as cell culture substrates. Results We found that tendon sections can be viewed as a pre-formed block of ECM in which the collagen fibrils exhibited a spatial regularity unraveled in any artificially constructed scaffold. By carving the tendon at different angles relative to its main axis, we created different surfaces with distinct spatial arrangements of collagen fibrils. To assess the cellular responses to these surfaces, human mesenchymal stem cells (MSCs) were directly cultured on these sections, hence exposed to the collagen with different spatial orientations. Cells seeded on longitudinal tendon sections adopted a highly elongated and aligned morphology, and expressed an increased level of tenomodulin, suggesting that the collagen fibrils present in this section provide a microenvironment that facilitates cell morphogenesis and differentiation. However, MSC elongation, alignment and induction of tenomodulin diminished dramatically even as the sectioned angle changed slightly. Conclusion Our results suggest that cell functions are influenced not only by the type or concentration of ECM components, but also by the precise spatial arrangements of these molecules. The method developed in this study offers a simple and robust way for the studying of cell-ECM interactions, and opens many research avenues in the field of matrix biology.
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Affiliation(s)
| | | | | | - Kelvin W K Yeung
- Department of Biology & Chemistry, City University of Hong Kong, Hong Kong, China.
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35
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Li ZF, Liang YM, Lau PN, Shen W, Wang DK, Cheung WT, Xue CJ, Poon LM, Lam YW. Dynamic localisation of mature microRNAs in Human nucleoli is influenced by exogenous genetic materials. PLoS One 2013; 8:e70869. [PMID: 23940654 PMCID: PMC3735495 DOI: 10.1371/journal.pone.0070869] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Accepted: 06/26/2013] [Indexed: 11/18/2022] Open
Abstract
Although microRNAs are commonly known to function as a component of RNA-induced silencing complexes in the cytoplasm, they have been detected in other organelles, notably the nucleus and the nucleolus, of mammalian cells. We have conducted a systematic search for miRNAs in HeLa cell nucleoli, and identified 11 abundant miRNAs with a high level of nucleolar accumulation. Through in situ hybridisation, we have localised these miRNAs, including miR-191 and miR-484, in the nucleolus of a diversity of human and rodent cell lines. The nucleolar association of these miRNAs is resistant to various cellular stresses, but highly sensitive to the presence of exogenous nucleic acids. Introduction of both single- and double-stranded DNA as well as double stranded RNA rapidly induce the redistribution of nucleolar miRNAs to the cytoplasm. A similar change in subcellular distribution is also observed in cells infected with the influenza A virus. The partition of miRNAs between the nucleolus and the cytoplasm is affected by Leptomycin B, suggesting a role of Exportin-1 in the intracellular shuttling of miRNAs. This study reveals a previously unknown aspect of miRNA biology, and suggests a possible link between these small noncoding RNAs and the cellular management of foreign genetic materials.
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Affiliation(s)
- Zhou Fang Li
- Departments of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Yi Min Liang
- Departments of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Pui Ngan Lau
- Centre of Influenza Research and School of Public Health, The University of Hong Kong, Hong Kong, China
| | - Wei Shen
- Departments of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Dai Kui Wang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing Tai Cheung
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Chun Jason Xue
- Departments of Computer Science, City University of Hong Kong, Hong Kong, China
| | - Lit Man Poon
- Centre of Influenza Research and School of Public Health, The University of Hong Kong, Hong Kong, China
| | - Yun Wah Lam
- Departments of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
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Dong H, Cheung SH, Liang Y, Wang B, Ramalingam R, Wang P, Sun H, Cheng SH, Lam YW. “Stainomics”: Identification of mitotracker labeled proteins in mammalian cells. Electrophoresis 2013; 34:1957-64. [DOI: 10.1002/elps.201200557] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 03/27/2013] [Accepted: 03/28/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Hongjuan Dong
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Sau Ha Cheung
- Department of Surgery; The Chinese University of Hong Kong; Hong Kong
| | - Yimin Liang
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Baojiang Wang
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Rajkumar Ramalingam
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Ping Wang
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Hongyan Sun
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Shuk Han Cheng
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
| | - Yun Wah Lam
- Department of Biology and Chemistry; City University of Hong Kong; Kowloon; Hong Kong
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Babaei F, Ramalingam R, Tavendale A, Liang Y, Yan LSK, Ajuh P, Cheng SH, Lam YW. Novel Blood Collection Method Allows Plasma Proteome Analysis from Single Zebrafish. J Proteome Res 2013; 12:1580-90. [DOI: 10.1021/pr3009226] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Fatemeh Babaei
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - Rajkumar Ramalingam
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - Amy Tavendale
- Dundee Cell Products, James Lindsay Place, Dundee Technopole, Dundee DD1 5JJ, Scotland,
U.K
| | - Yimin Liang
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - Leo So Kin Yan
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - Paul Ajuh
- Dundee Cell Products, James Lindsay Place, Dundee Technopole, Dundee DD1 5JJ, Scotland,
U.K
| | - Shuk Han Cheng
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - Yun Wah Lam
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
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Liang YM, Wang X, Ramalingam R, So KY, Lam YW, Li ZF. Novel nucleolar isolation method reveals rapid response of human nucleolar proteomes to serum stimulation. J Proteomics 2012; 77:521-30. [DOI: 10.1016/j.jprot.2012.09.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 09/23/2012] [Accepted: 09/24/2012] [Indexed: 12/31/2022]
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Cai X, Ramalingam R, Wong HS, Cheng J, Ajuh P, Cheng SH, Lam YW. Characterization of carbon nanotube protein corona by using quantitative proteomics. Nanomedicine 2012; 9:583-93. [PMID: 23117048 DOI: 10.1016/j.nano.2012.09.004] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 07/02/2012] [Accepted: 09/29/2012] [Indexed: 02/06/2023]
Abstract
UNLABELLED The protein corona of a nanomaterial is a complex layer of proteins spontaneously and stably formed when the material is exposed to body fluids or intracellular environments. In this study, we utilised stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomics to characterise the binding of human cellular proteins to two forms of carbon nanoparticles: namely multi-walled carbon nanotubes (MWCNTs) and carbon black (CB). The relative binding efficiency of over 750 proteins to these materials is measured. The data indicate that MWCNTs and CB bind to vastly different sets of proteins. The molecular basis of selectivity in protein binding is investigated. This study is the first large-scale characterisation of protein corona on CNT, providing the biochemical basis for the assessment of the suitability of CNTs as biomedical tools, and as an emerging pollutant. FROM THE CLINICAL EDITOR This team of investigators performed the first large-scale characterization of protein corona on carbon nanotubes, studying 750 proteins and assessing the suitability of CNTs as biomedical tools and as an emerging pollutant.
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Affiliation(s)
- Xiaoning Cai
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong
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Tong WY, Shen W, Yeung CWF, Zhao Y, Cheng SH, Chu PK, Chan D, Chan GCF, Cheung KMC, Yeung KWK, Lam YW. Functional replication of the tendon tissue microenvironment by a bioimprinted substrate and the support of tenocytic differentiation of mesenchymal stem cells. Biomaterials 2012; 33:7686-98. [PMID: 22818988 DOI: 10.1016/j.biomaterials.2012.07.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 07/01/2012] [Indexed: 10/28/2022]
Abstract
Although many studies have demonstrated that cell phenotype is affected by the surface properties of biomaterials, these materials often fail to mimic the complexity of the native tissue microenvironment (TME). In this study, we have developed a new experimental model that allows the characterisation and functional reconstruction of natural TME. We discovered that mesenchymal stem cells (MSC) cultured on cryostat sections of bovine Achilles tendon adopted an elongated and aligned morphology, and expressed tenocyte marker tenomodulin (TNMD). This suggests that tendon sections contain the signalling cues that guide MSCs to commit to the tenogenic lineage. To reconstruct this instructive niche, we prepared PDMS replica by using tendon sections as template. The resulting bioimprint faithfully copied the physical topography and elasticity of the section. This replica, when coated with collagen 1, supported tenogenesis of MSC without requiring exogenous growth factors. This study illustrates how extracellular biophysical and biochemical features intertwines to form a niche that influences the cell fate and demonstrated that such complex information could be conveniently reconstructed with synthetic materials and purified extracellular matrix proteins.
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Affiliation(s)
- Wing Yin Tong
- Departments of Orthopaedics & Traumatology, The University of Hong Kong, Hong Kong, China
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Hutten S, Prescott A, James J, Riesenberg S, Boulon S, Lam YW, Lamond AI. An intranucleolar body associated with rDNA. Chromosoma 2011; 120:481-99. [PMID: 21698343 PMCID: PMC3232531 DOI: 10.1007/s00412-011-0327-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Revised: 05/16/2011] [Accepted: 05/31/2011] [Indexed: 02/07/2023]
Abstract
The nucleolus is the subnuclear organelle responsible for ribosome subunit biogenesis and can also act as a stress sensor. It forms around clusters of ribosomal DNA (rDNA) and is mainly organised in three subcompartments, i.e. fibrillar centre, dense fibrillar component and granular component. Here, we describe the localisation of 21 protein factors to an intranucleolar region different to these main subcompartments, called the intranucleolar body (INB). These factors include proteins involved in DNA maintenance, protein turnover, RNA metabolism, chromatin organisation and the post-translational modifiers SUMO1 and SUMO2/3. Increase in the size and number of INBs is promoted by specific types of DNA damage and depends on the functional integrity of the nucleolus. INBs are abundant in nucleoli of unstressed cells during S phase and localise in close proximity to rDNA with heterochromatic features. The data suggest the INB is linked with regulation of rDNA transcription and/or maintenance of rDNA.
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Affiliation(s)
- Saskia Hutten
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, UK
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Lim H, Utyuzhnikov SV, Lam YW, Turan A. Multi-domain active sound control and noise shielding. J Acoust Soc Am 2011; 129:717-725. [PMID: 21361431 DOI: 10.1121/1.3531933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper describes an active sound control methodology based on difference potentials. The main feature of this methodology is its ability to automatically preserve "wanted" sound within a domain while cancelling "unwanted" noise from outside the domain. This method of preservation of the wanted sounds by active shielding control is demonstrated with various broadband and realistic sound sources such as human voice and music in multiple domains in a one-dimensional enclosure. Unlike many other conventional active control methods, the proposed approach does not require the explicit characterization of the wanted sound to be preserved. The controls are designed based on the measurements of the total field on the boundaries of the shielded domain only, which is allowed to be multiply connected. The method is tested in a variety of experimental cases. The typical attenuation of the unwanted noise is found to be about 20 dB over a large area of the shielded domain and the original wanted sound field is preserved with errors of around 1 dB and below through a broad frequency range up to 1 kHz.
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Affiliation(s)
- H Lim
- Acoustics Research Centre, University of Salford, Salford, Greater Manchester M5 4WT, United Kingdom.
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Dong H, Shen W, Cheung MTW, Liang Y, Cheung HY, Allmaier G, Kin-Chung Au O, Lam YW. Rapid detection of apoptosis in mammalian cells by using intact cell MALDI mass spectrometry. Analyst 2011; 136:5181-9. [DOI: 10.1039/c1an15750g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Westman BJ, Verheggen C, Hutten S, Lam YW, Bertrand E, Lamond AI. A proteomic screen for nucleolar SUMO targets shows SUMOylation modulates the function of Nop5/Nop58. Mol Cell 2010; 39:618-31. [PMID: 20797632 PMCID: PMC2938476 DOI: 10.1016/j.molcel.2010.07.025] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 04/30/2010] [Accepted: 06/08/2010] [Indexed: 11/23/2022]
Abstract
Posttranslational SUMO modification is an important mechanism of regulating protein function, especially in the cell nucleus. The nucleolus is the subnuclear organelle responsible for rRNA synthesis, processing, and assembly of the large and small ribosome subunits. Here, we have used SILAC-based quantitative proteomics to identify nucleolar SUMOylated proteins. This reveals a role for SUMOylation in the biogenesis and/or function of small nucleolar ribonucleoprotein complexes (snoRNPs) via the targeting of Nhp2 and Nop58. Using combined in vitro and in vivo approaches, both Nhp2 and Nop58 (also known as Nop5) are shown to be substrates for SUMOylation. Mutational analyses revealed the sites of modification on Nhp2 as K5, and on Nop58 as K467 and K497. Unlike Nop58 and Nhp2, the closely related Nop56 and 15.5K proteins appear not to be SUMO targets. SUMOylation is essential for high-affinity Nop58 binding to snoRNAs. This study provides direct evidence linking SUMO modification with snoRNP function.
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Affiliation(s)
- Belinda J Westman
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD15EH, UK
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Tong WY, Liang YM, Tam V, Yip HK, Kao YT, Cheung KMC, Yeung KWK, Lam YW. Biochemical characterization of the cell-biomaterial interface by quantitative proteomics. Mol Cell Proteomics 2010; 9:2089-98. [PMID: 20562470 DOI: 10.1074/mcp.m110.001966] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Surface topography and texture of cell culture substrata can affect the differentiation and growth of adherent cells. The biochemical basis of the transduction of the physical and mechanical signals to cellular responses is not well understood. The lack of a systematic characterization of cell-biomaterial interaction is the major bottleneck. This study demonstrated the use of a novel subcellular fractionation method combined with quantitative MS-based proteomics to enable the robust and high-throughput analysis of proteins at the adherence interface of Madin-Darby canine kidney cells. This method revealed the enrichment of extracellular matrix proteins and membrane and stress fibers proteins at the adherence surface, whereas it shows depletion of extracellular matrix belonging to the cytoplasmic, nucleus, and lateral and apical membranes. The asymmetric distribution of proteins between apical and adherence sides was also profiled. Apart from classical proteins with clear involvement in cell-material interactions, proteins previously not known to be involved in cell attachment were also discovered.
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Affiliation(s)
- W Y Tong
- Department of Orthopaedics and Traumatology, LKS Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Pokfulam, Hong Kong
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Boisvert FM, Lam YW, Lamont D, Lamond AI. A quantitative proteomics analysis of subcellular proteome localization and changes induced by DNA damage. Mol Cell Proteomics 2009; 9:457-70. [PMID: 20026476 PMCID: PMC2849709 DOI: 10.1074/mcp.m900429-mcp200] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A major challenge in cell biology is to identify the subcellular distribution of proteins within cells and to characterize how protein localization changes under different cell growth conditions and in response to stress and other external signals. Protein localization is usually determined either by microscopy or by using cell fractionation combined with protein blotting techniques. Both these approaches are intrinsically low throughput and limited to the analysis of known components. Here we use mass spectrometry-based proteomics to provide an unbiased, quantitative, and high throughput approach for measuring the subcellular distribution of the proteome, termed “spatial proteomics.” The spatial proteomics method analyzes a whole cell extract created by recombining differentially labeled subcellular fractions derived from cells in which proteins have been mass-labeled with heavy isotopes. This was used here to measure the relative distribution between cytoplasm, nucleus, and nucleolus of over 2,000 proteins in HCT116 cells. The data show that, at steady state, the proteome is predominantly partitioned into specific subcellular locations with only a minor subset of proteins equally distributed between two or more compartments. Spatial proteomics also facilitates a proteome-wide comparison of changes in protein localization in response to a wide range of physiological and experimental perturbations, shown here by characterizing dynamic changes in protein localization elicited during the cellular response to DNA damage following treatment of HCT116 cells with etoposide. DNA damage was found to cause dissociation of the proteasome from inhibitory proteins and assembly chaperones in the cytoplasm and relocation to associate with proteasome activators in the nucleus.
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Affiliation(s)
- François-Michel Boisvert
- The Wellcome Trust Centre for Gene Regulation and Expression, University of Dundee, MSI/WTB/JBC Complex, Dow Street, Dundee DD1 5EH, Scotland, United Kingdom
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Wang X, Lau KKK, So LKY, Lam YW. CHD5 is down-regulated through promoter hypermethylation in gastric cancer. J Biomed Sci 2009; 16:95. [PMID: 19840376 PMCID: PMC2770510 DOI: 10.1186/1423-0127-16-95] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2009] [Accepted: 10/19/2009] [Indexed: 01/25/2023] Open
Abstract
Background Nonhistone chromosomal proteins in concert with histones play important roles in the replication and repair of DNA and in the regulation of gene expression. The deregulation of these proteins can contribute to the development of a variety of diseases such as cancer. As a nonhistone chromosomal protein, chromodomain helicase DNA binding protein 5 (CHD5) has recently been identified as the product of a novel tumor suppressor gene (TSG), promoting the transcription of p19ink4a and p16arf. The inactivation of CHD5 was achieved partly through genetic deletion since it is located in 1p36, a region frequently deleted in human tumors. In this study, we aim to study the involvement of CHD5 in gastric cancer, the second most common cancer worldwide. Methods CHD5 expression in a panel of gastric cancer cells were determined by quantitative RT-PCR. The methylation of CHD5 was evaluated by methylation specific PCR and bisulfite genome sequencing. The effect of CHD5 on growth of gastric cancer cells was tested by colony formation assay. Results CHD5 expression was down-regulated in all of gastric cancer cell lines used (100%, 7/7) and significantly restored after pharmacological demethylation. Methylation of CHD5 promoter was detected in all of seven gastric cancer cell lines and in the majority of primary gastric carcinoma tissues examined (73%, 11/15). Finally, ectopic expression of CHD5 in gastric cancer cells led to a significant growth inhibition. Conclusion CHD5 was a TSG epigenetically down-regulated in gastric cancer.
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Affiliation(s)
- Xian Wang
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR, China.
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Gu YJ, Cheng J, Lin CC, Lam YW, Cheng SH, Wong WT. Nuclear penetration of surface functionalized gold nanoparticles. Toxicol Appl Pharmacol 2009; 237:196-204. [DOI: 10.1016/j.taap.2009.03.009] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2009] [Revised: 03/12/2009] [Accepted: 03/19/2009] [Indexed: 10/21/2022]
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Trinkle-Mulcahy L, Boulon S, Lam YW, Urcia R, Boisvert FM, Vandermoere F, Morrice NA, Swift S, Rothbauer U, Leonhardt H, Lamond A. Identifying specific protein interaction partners using quantitative mass spectrometry and bead proteomes. ACTA ACUST UNITED AC 2008; 183:223-39. [PMID: 18936248 PMCID: PMC2568020 DOI: 10.1083/jcb.200805092] [Citation(s) in RCA: 349] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The identification of interaction partners in protein complexes is a major goal in cell biology. Here we present a reliable affinity purification strategy to identify specific interactors that combines quantitative SILAC-based mass spectrometry with characterization of common contaminants binding to affinity matrices (bead proteomes). This strategy can be applied to affinity purification of either tagged fusion protein complexes or endogenous protein complexes, illustrated here using the well-characterized SMN complex as a model. GFP is used as the tag of choice because it shows minimal nonspecific binding to mammalian cell proteins, can be quantitatively depleted from cell extracts, and allows the integration of biochemical protein interaction data with in vivo measurements using fluorescence microscopy. Proteins binding nonspecifically to the most commonly used affinity matrices were determined using quantitative mass spectrometry, revealing important differences that affect experimental design. These data provide a specificity filter to distinguish specific protein binding partners in both quantitative and nonquantitative pull-down and immunoprecipitation experiments.
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Affiliation(s)
- Laura Trinkle-Mulcahy
- Wellcome Trust Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland, UK.
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Moorhead GBG, Trinkle-Mulcahy L, Nimick M, De Wever V, Campbell DG, Gourlay R, Lam YW, Lamond AI. Displacement affinity chromatography of protein phosphatase one (PP1) complexes. BMC Biochem 2008; 9:28. [PMID: 19000314 PMCID: PMC2587467 DOI: 10.1186/1471-2091-9-28] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Accepted: 11/10/2008] [Indexed: 01/21/2023]
Abstract
Background Protein phosphatase one (PP1) is a ubiquitously expressed, highly conserved protein phosphatase that dephosphorylates target protein serine and threonine residues. PP1 is localized to its site of action by interacting with targeting or regulatory proteins, a majority of which contains a primary docking site referred to as the RVXF/W motif. Results We demonstrate that a peptide based on the RVXF/W motif can effectively displace PP1 bound proteins from PP1 retained on the phosphatase affinity matrix microcystin-Sepharose. Subsequent co-immunoprecipitation experiments confirmed that each identified binding protein was either a direct PP1 interactor or was in a complex that contains PP1. Our results have linked PP1 to numerous new nuclear functions and proteins, including Ki-67, Rif-1, topoisomerase IIα, several nuclear helicases, NUP153 and the TRRAP complex. Conclusion This modification of the microcystin-Sepharose technique offers an effective means of purifying novel PP1 regulatory subunits and associated proteins and provides a simple method to uncover a link between PP1 and additional cellular processes.
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Affiliation(s)
- Greg B G Moorhead
- Department of Biological Sciences, University of Calgary, 2500 University Dr, NW Calgary, AB T2N 1N4, Canada.
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