Single fluorescent protein-based Ca2+sensors with increased dynamic range

Souslova, Ekaterina A.; Belousov, Vsevolod V.; Lock, John G.; Strömblad, Staffan; Kasparov, Sergey; Bolshakov, A D; Pinelis, V. G.; Labas, Yulii A.; Lukyanov, Sergey; Mayr, Lorenz M.; Chudakov, Dmitriy M.

doi:10.1186/1472-6750-7-37

Cited by 102 publications

(81 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This targeting was achieved by inserting a mitochondrial signal peptide into the N terminus of the Case12 protein (mito-Case12). Case12 protein allows linear detection of Ca 2+ ion concentration within the physiological range and its binding to Ca 2+ is rapid and reversible, thus making real-time detection of changes in Ca 2+ level within a cell possible (20,21). Mito-Case12 colocalized with mito-RFP in transfected hippocampal neurons (Fig.…”

Section: Resultsmentioning

confidence: 99%

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons

Chang

Niescier

Min

2011

Proc. Natl. Acad. Sci. U.S.A.

138

111

View full text Add to dashboard Cite

The proper distribution of mitochondria is particularly vital for neurons because of their polarized structure and high energy demand. Mitochondria in axons constantly move in response to physiological needs, but signals that regulate mitochondrial movement are not well understood. Aside from producing ATP, Ca 2+ buffering is another main function of mitochondria. Activities of many enzymes in mitochondria are also Ca 2+ -dependent, suggesting that intramitochondrial Ca 2+ concentration is important for mitochondrial functions. Here, we report that mitochondrial motility in axons is actively regulated by mitochondrial matrix Ca 2+ . Ca 2+ entry through the mitochondrial Ca 2+ uniporter modulates mitochondrial transport, and mitochondrial Ca 2+ content correlates inversely with the speed of mitochondrial movement. Furthermore, the miro1 protein plays a role in Ca 2+ uptake into the mitochondria, which subsequently affects mitochondrial movement.M itochondria are dynamic organelles that constantly move within cells and undergo morphological changes in response to physiological needs (1-3). In neurons, mitochondria are abundantly present throughout different subcellular compartments. The machineries and signals that transport mitochondria from the cell body (where they are synthesized) to the terminal need to be carefully regulated because of the highly polarized structure and lengthy axon of a neuron (4-6). Defects in transport of mitochondria can cause deleterious effects on mitochondrial functions in different parts of neurons, and hence affect neuronal survival and function (2, 3). Recent efforts to investigate mitochondrial transportation have provided significant new information regarding mitochondrial mobility, especially the mechanical components that modulate mitochondrial transport; however, it remains unclear whether intrinsic signals inside of mitochondria also actively regulate mitochondrial movement.Mitochondrial transport is mediated by interactions of the mitochondrial adaptor proteins to the kinesin and dynein motors, as well as binding of the motor proteins to the cytoskeleton track (7,8). It was posited that cytoplasmic Ca 2+ level is a key regulator of mitochondrial trafficking in axons and dendrites, and that intracellular Ca 2+ influx impedes mitochondrial movement by affecting the overall interactions between the mitochondrial adaptor, motor, and cytoskeleton track (9, 10). Two different mechanisms for Ca 2+ -mediated stop in mitochondrial trafficking were proposed. Wang and Schwarz suggested that Ca 2+ binding to the EF hand motif of the mitochondrial adaptor protein miro1 recruits kinesin-1 motor and, hence, derails kinesin-1 from the microtubule track, thereby stopping mitochondrial transportation in axons (10). Macaskill et al. proposed that following Ca 2+ influx induced by glutamate or neuronal activity, Ca 2+ binding to the EF hand motif of the miro1 protein causes miro1 to dissociate from the kinesin-1 motor, and hence halts mitochondrial movement (11). Although the mechanisms propose...

show abstract

Section: Resultsmentioning

confidence: 99%

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons

Chang

Niescier

Min

2011

Proc. Natl. Acad. Sci. U.S.A.

138

111

View full text Add to dashboard Cite

show abstract

“…Thus, a 2-fold increase in total dynamic range for FRET-based GECIs seems plausible. In the single FP instance, Case-16 shows a 16-fold DF/F 0 in vitro (Souslova et al, 2007), 3-fold better than G-CaMP2. If such improvements hold in situ, this will result in significantly better SNR.…”

Section: Practical Improvementsmentioning

confidence: 93%

Reporting neural activity with genetically encoded calcium indicators

2008

View full text Add to dashboard Cite

Genetically encoded calcium indicators (GECIs), based on recombinant fluorescent proteins, have been engineered to observe calcium transients in living cells and organisms. Through observation of calcium, these indicators also report neural activity. We review progress in GECI construction and application, particularly toward in vivo monitoring of sparse action potentials (APs). We summarize the extrinsic and intrinsic factors that influence GECI performance. A simple model of GECI response to AP firing demonstrates the relative significance of these factors. We recommend a standardized protocol for evaluating GECIs in a physiologically relevant context. A potential method of simultaneous optical control and recording of neuronal circuits is presented.

show abstract

“…It should be noted, however, that all PAS-GAF pairs have a unique 4-crossover knot, which may complicate protein reconstitution. Once the right position to make a split or add an insertion is determined, the next step is the optimization of linkers between the PAS and GAF domains and the fused sensing moieties 60,61 . A reversibility of fluorescence resulting from association-dissociation of the sensing moieties in biosensors remains to be studied.…”

Section: Biosensorsmentioning

confidence: 99%

Engineering of Bacterial Phytochromes for Near-Infrared Imaging, Sensing and Light-Control in Mammals

Shcherbakova

Kaberniuk

Redchuk

et al. 2018

Biophysical Journal

View full text Add to dashboard Cite

Near-infrared light is favourable for imaging in mammalian tissues due to low absorbance of hemoglobin, melanin, and water. Therefore, fluorescent proteins, biosensors and optogenetic constructs for optimal imaging, optical readout and light manipulation in mammals should have fluorescence and action spectra within the near-infrared window. Interestingly, natural Bacterial Phytochrome Photoreceptors (BphPs) utilize the low molecular weight biliverdin, found in most mammalian tissues, as a photoreactive chromophore. Due to their near-infrared absorbance BphPs are preferred templates for designing optical molecular tools for applications in mammals. Moreover, BphPs spectrally complement existing genetically-encoded probes. Several BphPs were already developed into the near-infrared fluorescent variants. Based on analysis of the photochemistry and structure of BphPs we suggest a variety of possible BphP-based fluorescent proteins, biosensors, and optogenetic tools. Putative design strategies and experimental considerations for such probes are discussed.

show abstract

Single fluorescent protein-based Ca2+sensors with increased dynamic range

Cited by 102 publications

References 28 publications

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons

Reporting neural activity with genetically encoded calcium indicators

Engineering of Bacterial Phytochromes for Near-Infrared Imaging, Sensing and Light-Control in Mammals

Contact Info

Product

Resources

About

Single fluorescent protein-based Ca2+sensors with increased dynamic range

Cited by 102 publications

References 28 publications

Mitochondrial matrix Ca 2 + as an intrinsic signal regulating mitochondrial motility in axons

Mitochondrial matrix Ca 2 + as an intrinsic signal regulating mitochondrial motility in axons

Reporting neural activity with genetically encoded calcium indicators

Engineering of Bacterial Phytochromes for Near-Infrared Imaging, Sensing and Light-Control in Mammals

Contact Info

Product

Resources

About

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons

Mitochondrial matrix Ca ² ⁺ as an intrinsic signal regulating mitochondrial motility in axons