1
|
Cao X, Wang W, Jiang Y, Feng W, Xu S, Xu W, Zhang W. An atomic force microscopy and total internal reflection fluorescence microscopy correlated system (AFM-TIRF) for fluorescence imaging and spectroscopy of a single particle. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:073706. [PMID: 38995931 DOI: 10.1063/5.0210704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024]
Abstract
Combining atomic force microscopy (AFM) with other optical microscopic techniques is pivotal in nanoscale investigations, particularly leveraging the surface-sensitive properties of total internal reflection fluorescence microscopy (TIRF). A novel design that integrates AFM with a multi-wavelength TIRF is displayed, providing simultaneous fluorescence imaging and spectral acquisition capabilities. We elaborate on the considerations in the instrument design process and demonstrate the performance and potential applications of the instrument through fluorescence imaging and spectroscopy testing of individual nanoparticles. This AFM and TIRF correlated system (AFM-TIRF) emerges as a promising option for single-molecule fluorescence studies, enabling simultaneous manipulation and detection of fluorescence from individual molecules.
Collapse
Affiliation(s)
- Xiumian Cao
- College of Physics, Jilin University, Changchun 130012, People's Republic of China
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
| | - Wenquan Wang
- College of Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Yuanfei Jiang
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Wei Feng
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, People's Republic of China
| | - Shuping Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
- Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
| | - Weiqing Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
| | - Wenke Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
- Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China
| |
Collapse
|
2
|
Ros U, Pedrera L, Garcia-Saez AJ. Techniques for studying membrane pores. Curr Opin Struct Biol 2021; 69:108-116. [PMID: 33945958 DOI: 10.1016/j.sbi.2021.03.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 01/30/2023]
Abstract
Pore-forming proteins (PFPs) are of special interest because of the association of their activity with the disruption of the membrane impermeability barrier and cell death. They generally convert from a monomeric, soluble form into transmembrane oligomers that induce the opening of membrane pores. The study of pore formation in membranes with molecular detail remains a challenging endeavor because of its highly dynamic and complex nature, usually involving diverse oligomeric structures with different functionalities. Here we discuss current methods applied for the structural and functional characterization of PFPs at the individual vesicle and cell level. We highlight how the development of high-resolution and single-molecule imaging techniques allows the analysis of the structural organization of protein oligomers and pore entities in lipid membranes.
Collapse
Affiliation(s)
- Uris Ros
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany
| | - Lohans Pedrera
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany
| | - Ana J Garcia-Saez
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany.
| |
Collapse
|
3
|
Alunda BO, Lee YJ. Review: Cantilever-Based Sensors for High Speed Atomic Force Microscopy. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4784. [PMID: 32854193 PMCID: PMC7506678 DOI: 10.3390/s20174784] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/11/2020] [Accepted: 08/12/2020] [Indexed: 12/13/2022]
Abstract
This review critically summarizes the recent advances of the microcantilever-based force sensors for atomic force microscope (AFM) applications. They are one the most common mechanical spring-mass systems and are extremely sensitive to changes in the resonant frequency, thus finding numerous applications especially for molecular sensing. Specifically, we comment on the latest progress in research on the deflection detection systems, fabrication, coating and functionalization of the microcantilevers and their application as bio- and chemical sensors. A trend on the recent breakthroughs on the study of biological samples using high-speed atomic force microscope is also reported in this review.
Collapse
Affiliation(s)
- Bernard Ouma Alunda
- School of Mines and Engineering, Taita Taveta University, P.O. Box 635-80300 Voi, Kenya;
| | - Yong Joong Lee
- School of Mechanical Engineering, Kyungpook National University, Daegu 41566, Korea
| |
Collapse
|
4
|
Viji Babu PK, Radmacher M. Mechanics of Brain Tissues Studied by Atomic Force Microscopy: A Perspective. Front Neurosci 2019; 13:600. [PMID: 31258462 PMCID: PMC6587663 DOI: 10.3389/fnins.2019.00600] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/27/2019] [Indexed: 01/17/2023] Open
Abstract
Tissue morphology and mechanics are crucial to the regulation of organ function. Investigating the exceptionally complex tissue of the brain at the sub-micron scale is challenging due to the complex structure and softness of this tissue, despite the large interest of biologists, medical engineers, biophysicists, and others in this topic. Atomic force microscopy (AFM) both as an imaging and as a mechanical tool provides an excellent opportunity to study soft biological samples such as live brain tissues. Here we review the principles of AFM, the performance of AFM in tissue imaging and mechanical mapping of cells and tissues, and finally opening the prospects and challenges of probing the biophysical properties of brain tissue using AFM.
Collapse
|
5
|
Cosentino K, Ros U, García-Sáez AJ. Assembling the puzzle: Oligomerization of α-pore forming proteins in membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:457-466. [PMID: 26375417 DOI: 10.1016/j.bbamem.2015.09.013] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/26/2015] [Accepted: 09/09/2015] [Indexed: 12/21/2022]
Abstract
Pore forming proteins (PFPs) share the ability of creating pores that allow the passage of ions, proteins or other constituents through a wide variety of target membranes, ranging from bacteria to humans. They often cause cell death, as pore formation disrupts the membrane permeability barrier required for maintaining cell homeostasis. The organization into supramolecular complexes or oligomers that pierce the membrane is a common feature of PFPs. However, the molecular pathway of self-assembly and pore opening remains unclear. Here, we review the most recent discoveries in the mechanism of membrane oligomerization and pore formation of a subset of PFPs, the α-PFPs, whose pore-forming domains are formed by helical segments. Only now we are starting to grasp the molecular details of their function, mainly thanks to the introduction of single molecule microscopy and nanoscopy techniques. This article is part of a Special Issue entitled: Pore-forming toxins edited by Mauro Dalla Serra and Franco Gambale.
Collapse
Affiliation(s)
- Katia Cosentino
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Tübingen, Germany.,Max-Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Uris Ros
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Tübingen, Germany.,Max-Planck Institute for Intelligent Systems, Stuttgart, Germany.,Center for Protein Studies, Havana University, Havana, Cuba
| | - Ana J García-Sáez
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Tübingen, Germany.,Max-Planck Institute for Intelligent Systems, Stuttgart, Germany
| |
Collapse
|
6
|
Meckes B, Ambrosi C, Barnard H, Arce FT, Sosinsky GE, Lal R. Atomic force microscopy shows connexin26 hemichannel clustering in purified membrane fragments. Biochemistry 2014; 53:7407-14. [PMID: 25365227 PMCID: PMC4255643 DOI: 10.1021/bi501265p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
![]()
Connexin
proteins form hexameric assemblies known as hemichannels.
When docked to form gap junction (GJ) channels, hemichannels play
a critical role in cell–cell communication and cellular homeostasis,
but often are functional entities on their own in unapposed cell membranes.
Defects in the Connexin26 (Cx26) gene are the major cause of hereditary
deafness arising from dysfunctional hemichannels in the cochlea. Structural
studies of Cx26 hemichannels properly trafficked and inserted in plasma
membranes, including their clustering that forms a plaque-like feature
in whole gap junctions, are limited. We used atomic force microscopy
(AFM) to study the surface topography of Cx26 hemichannels using two
different membrane preparations. Rat Cx26 containing appended carboxy
terminal V5 and hexahistidine tags were expressed in baculovirus/Sf9
cell systems. The expressed Cx26 proteins form hemichannels in situ
in Sf9 cells that were then purified either as (1) Sf9 membrane fragments
containing Cx26 hemichannels or (2) solubilized hemichannels. The
latter were subsequently reconstituted in liposomes. AFM images of
purified membrane fragments showed clusters of protein macromolecular
structures in the membrane that at higher magnification corresponded
to Cx26 hemichannels. Hemichannels reconstituted into DOPC bilayers
displayed two populations of channel heights likely resulting from
differences in orientations of inserted hemichannels. Hemichannels
in the protein rich portions of purified membranes also showed a reduced
channel height above the bilayer compared to membranes with reconstituted
hemichannels perhaps due to reduced AFM probe access to the lipid
bilayer. These preparations of purified membranes enriched for connexin
hemichannels that have been properly trafficked and inserted in membranes
provide a platform for high-resolution AFM imaging of the structure,
interconnexon interactions, and cooperativity of properly trafficked
and inserted noncrystalline connexin hemichannels.
Collapse
Affiliation(s)
- Brian Meckes
- Department of Bioengineering, ‡National Center for Microscopy and Imaging Research, §Department of Aerospace and Mechanical Engineering, ∥Department of Neurosciences, and ⊥Materials Science Program, University of California San Diego , 9500 Gillman Drive, La Jolla, California 92093, United States
| | | | | | | | | | | |
Collapse
|