scholarly journals Defining the Basis of Cyanine Phototruncation Enables a New Approach to Single Molecule Localization Microscopy

2021 ◽  
Author(s):  
Siddharth Matikonda ◽  
Dominic Helmerich ◽  
Mara Meub ◽  
Gerti Beliu ◽  
Philip Kollmannsberger ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Single Molecule ◽  
Computational Analysis ◽  
Super Resolution ◽  
Underlying Mechanism ◽  
New Approach ◽  
Localization Microscopy ◽  
Order Of Magnitude ◽  
Resolution Single ◽  
Single Molecule Localization Microscopy

<p>The light-promoted conversion of extensively used cyanine dyes to blue-shifted emissive products has been observed in various contexts. However, both the underlying mechanism and the species involved in this photoconversion reaction have remained elusive. Here we report that irradiation of heptamethine cyanines provides pentamethine cyanines, which, in turn, are photoconverted to trimethine cyanines. We detail an examination of the mechanism and substrate scope of this remarkable two-carbon phototruncation reaction. Supported by computational analysis, we propose that this reaction involves a singlet oxygen-initiated multi-step sequence involving a key hydroperoxycyclobutanol intermediate. Building on this mechanistic framework, we identify conditions to improve the yield of photoconversion by over an order of magnitude. We then demonstrate that cyanine phototruncation can be applied to super-resolution single-molecule localization microscopy, leading to improved spatial resolution with shorter imaging times. We anticipate these insights will help transform a common, but previously mechanistically ill-defined, chemical transformation into a valuable optical tool.</p>

scholarly journals Defining the Basis of Cyanine Phototruncation Enables a New Approach to Single Molecule Localization Microscopy

2021 ◽  
Author(s):  
Siddharth Matikonda ◽  
Dominic Helmerich ◽  
Mara Meub ◽  
Gerti Beliu ◽  
Philip Kollmannsberger ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Single Molecule ◽  
Computational Analysis ◽  
Super Resolution ◽  
Underlying Mechanism ◽  
New Approach ◽  
Localization Microscopy ◽  
Order Of Magnitude ◽  
Resolution Single ◽  
Single Molecule Localization Microscopy

<p>The light-promoted conversion of extensively used cyanine dyes to blue-shifted emissive products has been observed in various contexts. However, both the underlying mechanism and the species involved in this photoconversion reaction have remained elusive. Here we report that irradiation of heptamethine cyanines provides pentamethine cyanines, which, in turn, are photoconverted to trimethine cyanines. We detail an examination of the mechanism and substrate scope of this remarkable two-carbon phototruncation reaction. Supported by computational analysis, we propose that this reaction involves a singlet oxygen-initiated multi-step sequence involving a key hydroperoxycyclobutanol intermediate. Building on this mechanistic framework, we identify conditions to improve the yield of photoconversion by over an order of magnitude. We then demonstrate that cyanine phototruncation can be applied to super-resolution single-molecule localization microscopy, leading to improved spatial resolution with shorter imaging times. We anticipate these insights will help transform a common, but previously mechanistically ill-defined, chemical transformation into a valuable optical tool.</p>

scholarly journals Quantitative super-resolution single molecule microscopy dataset of YFP-tagged growth factor receptors

2018 ◽  
Author(s):  
Tomáš Lukeš ◽  
Jakub Pospíšil ◽  
Karel Fliegel ◽  
Theo Lasser ◽  
Guy M. Hagen
Keyword(s):  
Data Analysis ◽  
Growth Factor ◽  
Single Molecule ◽  
Super Resolution ◽  
Growth Factor Receptors ◽  
Data Sets ◽  
Localization Microscopy ◽  
Super Resolution Microscopy ◽  
Resolution Single ◽  
Single Molecule Localization Microscopy

BackgroundSuper-resolution single molecule localization microscopy (SMLM) is a method for achieving resolution beyond the classical limit in optical microscopes (approx. 200 nm laterally). Yellow fluorescent protein (YFP) has been used for super-resolution single molecule localization microscopy, but less frequently than other fluorescent probes. Working with YFP in SMLM is a challenge because a lower number of photons are emitted per molecule compared to organic dyes which are more commonly used. Publically available experimental data can facilitate development of new data analysis algorithms.FindingsFour complete, freely available single molecule super-resolution microscopy datasets on YFP-tagged growth factor receptors expressed in a human cell line are presented including both raw and analyzed data. We report methods for sample preparation, for data acquisition, and for data analysis, as well as examples of the acquired images. We also analyzed the SMLM data sets using a different method: super-resolution optical fluctuation imaging (SOFI). The two modes of analysis offer complementary information about the sample. A fifth single molecule super-resolution microscopy dataset acquired with the dye Alexa 532 is included for comparison purposes.ConclusionThis dataset has potential for extensive reuse. Complete raw data from SMLM experiments has typically not been published. The YFP data exhibits low signal to noise ratios, making data analysis a challenge. These data sets will be useful to investigators developing their own algorithms for SMLM, SOFI, and related methods. The data will also be useful for researchers investigating growth factor receptors such as ErbB3.

scholarly journals A H-bond strategy to develop acid-resistant photoswitchable rhodamine spirolactams for super-resolution single-molecule localization microscopy

2019 ◽  
Vol 10 (18) ◽  
pp. 4914-4922 ◽  
Author(s):  
Qingkai Qi ◽  
Weijie Chi ◽  
Yuanyuan Li ◽  
Qinglong Qiao ◽  
Jie Chen ◽  
...  
Keyword(s):  
Single Molecule ◽  
Super Resolution ◽  
Amino Groups ◽  
Localization Microscopy ◽  
Resolution Imaging ◽  
Resolution Single ◽  
Single Molecule Localization Microscopy

Rhodamine spirolactams with adjacent amino groups work as acid-resistant and photoswitchable fluorophores in single-molecule localization super-resolution imaging.

scholarly journals Super-resolution fight club: assessment of 2D and 3D single-molecule localization microscopy software

2019 ◽  
Vol 16 (5) ◽  
pp. 387-395 ◽  
Author(s):  
Daniel Sage ◽  
Thanh-An Pham ◽  
Hazen Babcock ◽  
Tomas Lukes ◽  
Thomas Pengo ◽  
...  
Keyword(s):  
Single Molecule ◽  
Super Resolution ◽  
Localization Microscopy ◽  
Fight Club ◽  
2D And 3D ◽  
Single Molecule Localization Microscopy

scholarly journals Super-resolution fight club: A broad assessment of 2D & 3D single-molecule localization microscopy software

2018 ◽  
Author(s):  
Daniel Sage ◽  
Thanh-An Pham ◽  
Hazen Babcock ◽  
Tomas Lukes ◽  
Thomas Pengo ◽  
...  
Keyword(s):  
Single Molecule ◽  
Double Helix ◽  
Super Resolution ◽  
Large Set ◽  
Holistic View ◽  
Localization Microscopy ◽  
Fight Club ◽  
Community Effort ◽  
2D And 3D ◽  
Single Molecule Localization Microscopy

ABSTRACTWith the widespread uptake of 2D and 3D single molecule localization microscopy, a large set of different data analysis packages have been developed to generate super-resolution images. To guide researchers on the optimal analytical software for their experiments, we have designed, in a large community effort, a competition to extensively characterise and rank these options. We generated realistic simulated datasets for popular imaging modalities – 2D, astigmatic 3D, biplane 3D, and double helix 3D – and evaluated 36 participant packages against these data. This provides the first broad assessment of 3D single molecule localization microscopy software, provides a holistic view of how the latest 2D and 3D single molecule localization software perform in realistic conditions, and ultimately provides insight into the current limits of the field.

scholarly journals Molecular resolution imaging by post-labeling expansion single-molecule localization microscopy (Ex-SMLM)

2020 ◽  
Author(s):  
Fabian U. Zwettler ◽  
Sebastian Reinhard ◽  
Davide Gambarotto ◽  
Toby D. M. Bell ◽  
Virginie Hamel ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Single Molecule ◽  
Super Resolution ◽  
Reference Structure ◽  
Positional Error ◽  
Localization Microscopy ◽  
Resolution Imaging ◽  
Endogenous Proteins ◽  
Super Resolution Microscopy ◽  
Single Molecule Localization Microscopy

AbstractExpansion microscopy (ExM) enables super-resolution fluorescence imaging of physically expanded biological samples with conventional microscopes. By combining expansion microscopy (ExM) with single-molecule localization microscopy (SMLM) it is potentially possible to approach the resolution of electron microscopy. However, current attempts to combine both methods remained challenging because of protein and fluorophore loss during digestion or denaturation, gelation, and the incompatibility of expanded polyelectrolyte hydrogels with photoswitching buffers. Here we show that re-embedding of expanded hydrogels enables dSTORM imaging of expanded samples and demonstrate that post-labeling ExM resolves the current limitations of super-resolution microscopy. Using microtubules as a reference structure and centrioles, we demonstrate that post-labeling Ex-SMLM preserves ultrastructural details, improves the labeling efficiency and reduces the positional error arising from linking fluorophores into the gel thus paving the way for super-resolution imaging of immunolabeled endogenous proteins with true molecular resolution.

scholarly journals Systematic Tuning of Rhodamine Spirocyclization for Super-Resolution Microscopy

2021 ◽  
Author(s):  
Nicolas Lardon ◽  
Lu Wang ◽  
Aline Tschanz ◽  
Philipp Hoess ◽  
Mai Tran ◽  
...  
Keyword(s):  
Single Molecule ◽  
Large Range ◽  
Dynamic Equilibrium ◽  
Super Resolution ◽  
Live Cell ◽  
Stimulated Emission ◽  
Important Class ◽  
Localization Microscopy ◽  
Super Resolution Microscopy ◽  
Single Molecule Localization Microscopy

Rhodamines are the most important class of fluorophores for applications in live-cell fluorescence microscopy. This is mainly because rhodamines exist in a dynamic equilibrium between a fluorescent zwitterion and a non-fluorescent but cell-permeable spirocyclic form. Different imaging applications require different positions of this dynamic equilibrium, which poses a challenge for the design of suitable probes. We describe here how the conversion of the ortho-carboxy moiety of a given rhodamine into substituted acyl benzenesulfonamides and alkylamides permits the systematic tuning of the equilibrium of spirocyclization with unprecedented accuracy and over a large range. This allows to transform the same rhodamine into either a highly fluorogenic and cell-permeable probe for live-cell stimulated emission depletion (STED) microscopy, or into a spontaneously blinking dye for single molecule localization microscopy (SMLM). We used this approach to generate differently colored probes optimized for different labeling systems and imaging applications.

Sign in / Sign up

Export Citation Format

Share Document