Voltage-sensitive sensors are still a very promising dream of the future. Hopefully this ‘holy grail’ sensor will replace our ‘old friend’, the GCaMP family. In principle, this ‘holy grail’ could enable extremely high temporal resolution of spiking and synaptic activity even in large neuronal populations. Moreover, it could be a gamechanger in dendritic integration experiments as well. At Columbia University Rafael Yuste and his colleagues published a quite impressive review which summarize the recent important findings about these indicators. All the important information could be found in this article. Let’s image!
Historical overview of genetic voltage indicators.
Source: Bando, Y., Grimm, C., Cornejo, V.H. et al. Genetic voltage indicators. BMC Biol 17, 71 (2019). https://doi.org/10.1186/s12915-019-0682-0
Let's help the research in Europe. Some scientists noticed there is significant reason to fear a cut the next European Research and Innovation Program, and they anticipate that this would also impact the European Research Council (ERC) funds.
ERC grants have become one of the most prestigious research grants in the world.
ERC has amazing statistics:
- 75% of completed projects led to breakthroughs or major advances.
- ERC-grantees have received 7 Nobel Prizes, 4 Kavli Prizes and 4 Fields Medals
- Over 9,500 top researchers have been funded, with 2/3 of grantees under 40 years old.
- Over 70,000 team members, mostly PhD students and postdocs, supported – training the next generation of excellent researchers.
- ERC research led to over 100,000 articles published, with more than 5,500 articles in the 1% most cited international scientific journals.
- ERC projects have led to over 1,200 patent applications and over 100 new ventures.
Here is the link where you can sign the petition!
Ultra-wide field functional imaging becomes quite popular nowadays. More and more scientists want to image on large field of view and single-cell resolution at the same time. Unfortunately, there are some serious tradeoffs among those desires. A Japanese team claims they solved these optical, mechanical, and biological problems. So here are the facts: 3x3 mm FOV, over 16000 identified neurons, 7.5 Hz sampling rate and excellent SNR. These novel engineering solutions might help us to see the bigger picture in neuroscience!
The original study was uploaded to bioRxiv.
Conventional objective lens (CFI Plan Fluor 10X/0.30, Nikon) and newly developed large objective, tube and scan lenses.
Unfortunately, we could not get tasty Scotch and nice beer this year at FENS. The city of Glasgow would have given place to FENS this year. But the event got canceled due to the tragic pandemic of Covid19. The organizers decided to go online. They did a great job and many participants came from different parts of the world.
It was great to have the lectures available with keeping the live online connection with the speakers. We could definitely attend more lectures than on a conference offline. We have not experienced any major issues during the lectures, but we could not attend all.
Here we have experienced some communication errors, but overall it was good. It was quite beneficial that even though I missed the time window of a poster, I could get answers from the authors later during the whole conference.
The exhibition section was not as good as in real life. It is good sometimes to take a walk and be amazed by the research tools which are presented at these conferences. All the vendors have different designs and useful or funny promotion gifts. But this year there was not much difference among the exhibitor booths. We still could chat with the representatives of the suppliers, but it was easy to avoid the salespeople who try to catch you for a short pitch.
Companies might reconsider to give the same or similar amount of investment to online conferences than to real offline events. There are many solutions to guide or force online participants to watch marketing materials before a lecture. This year there wasn't such an approach from the organizers, so all the lectures and posters were free of commercials.
It was the first major neuroscience conference in an online arena, and we think it passed the test. But there is still room to develop for the organizers. Virtualization can reach a higher level next year. Unfortunately, it will never reach the same level when we shake hands and exchange business cards. Stronger personal relationships rather form at a conference, which sometimes result in a good collaboration, a new job offer, or finding the right tool with the right deal.
We all hope everything will be back to normal and we will meet soon. :)
Since neuroscience has not got any popular two-photon compatible fast voltage sensitive dye, it is good to know some laboratories are still working on improved calcium fluorescence sensors. The brand new competitor is jYCaMP1. Dr. Kaspar Podgorski and his colleagues reported a red-shifted sensor which is compatible with affordable fixed wavelength laser sources. The jYCaMP1 is a redshifted variant of jGCaMP7 but it is 1.8-fold brighter and 1.6-fold ∆F/F in L2/3 V1 mouse neurons under 1,030nm illumination. The longer excitation wavelength also helps to go deeper in the tissue or even to increase the signal-to-noise ratio. They claimed even single action potentials can be detected which could open new horizons in behaving experiments. Let’s see how it will go!
Schematic of jYCaMP1 mutations (red spheres) overlaid on the GCaMP structure (right). One-photon and two-photon excitation and emission spectra.
New manufacturer on our site, the RWD Life Science specializes in life science, animal healthcare, and medical devices. Founded in 2002 and headquartered in Shenzhen, RWD is continuously establishing long-term partnerships with domestic and foreign universities. They invest in R&D to deliver innovation in products, technologies, and services. Based on serving customers around the world, RWD has not only achieved a strong reputation and advantage in the fields of respiratory anesthesia, neuroscience research, animal behavior research, surgery and nursing, and pathological analysis, but also gained constant trust and support from customers during the past almost two decades.
Absolute reliability, long term stability, and precision, are the features that describe a good micromanipulator. There are different manipulator types: hydraulic , piezoelectric , stepper motor. They all have different advantages, disadvantages compare to each other, but this will be presented in a longer blog section in August.
Most of the manipulators receive their control signals via wires. This is an industry-standard in all the companies, except one. MCI has tried something new. They decided on wireless technology. It was definitely a time, as wireless technology can be extremely stable just as a wired connection.
There is one potentially annoying problem what wireless techniques can solve. It is the wire itself, which sometime is in the way, or can be a pulling force on the manipulator. If the cable is not shielded well it can cause noise. Anyhow there are plenty wires either way around an ephys rig, so one less can help a bit. There is no price jump to go wireless, so MCI manipulators can offer all the requirements just without wires.
Image deconvolution and computational fusion of multiple views of the same sample could be very expansive or time-consuming processes. Hari Shroff and his colleagues have published new tools which can accelerate multiview image fusion and deconvolution as well. They claim these novel tools can increase speed up to ten-fold to several thousand-fold. They showed nice examples of superresolution, large brain tissue and various biological samples.
Their software is also freely available and maintained through GitHub. The software includes four sets of programs for implementing (1) WB deconvolution on a variety of different microscopes; (2) rapid registration of two volumetric images, for example, for subsequent WB deconvolution; (3) registration and deconvolution of large cleared-tissue datasets, imaged with diSPIM; and (4) our convolutional neural network (DenseDeconNet) for resolution recovery. Programs run in MATLAB except for DenseDeconNet, which is written in Python.
Source: Guo, M., Li, Y., Su, Y. et al. Rapid image deconvolution and multiview fusion for optical microscopy. Nat Biotechnol (2020).
For more information please visit: https://www.nature.com/articles/s41587-020-0560-x
Millimeter-scale cleared tissue of a mouse brain.
MCI Neuroscience is here!
Micro Control Instruments Ltd. is a neuroscience equipment developer and integrator. They are a leading innovator in deep tissue imaging, stimulation and recording in vivo.
See their offers at #NeuroRigBuilder.
How can we understand better complex neural processes such as dendritic integration and encoding? The objects are always in a volume not just in one single plane and we can not see the bigger picture without recording the whole volume. In a recent paper Dr. Sakaki and his colleagues developed a two-photon microscope which using acousto-optic deflectors for ultrafast 3D scanning. It enables random-access sampling of thousands of points-of-interest. They showed nice examples on tectal neurons in albino Xenopus laevis tadpoles brain. They used single-cell electroporation for expression of a red space-filling fluorophore to determine dendritic arbor morphology, and either the calcium sensor jGCaMP7s or the glutamate sensor iGluSnFR as indicators of neural activity. These cutting-edge techniques allow examining complex input-output patterns within an intact brain.
Excellent electroporators can be also find here at #NeuroRigBuilder: link