@article{12349, abstract = {Statistics of natural scenes are not uniform - their structure varies dramatically from ground to sky. It remains unknown whether these non-uniformities are reflected in the large-scale organization of the early visual system and what benefits such adaptations would confer. Here, by relying on the efficient coding hypothesis, we predict that changes in the structure of receptive fields across visual space increase the efficiency of sensory coding. We show experimentally that, in agreement with our predictions, receptive fields of retinal ganglion cells change their shape along the dorsoventral retinal axis, with a marked surround asymmetry at the visual horizon. Our work demonstrates that, according to principles of efficient coding, the panoramic structure of natural scenes is exploited by the retina across space and cell-types.}, author = {Gupta, Divyansh and Mlynarski, Wiktor F and Sumser, Anton L and Symonova, Olga and Svaton, Jan and Jösch, Maximilian A}, issn = {1546-1726}, journal = {Nature Neuroscience}, pages = {606--614}, publisher = {Springer Nature}, title = {{Panoramic visual statistics shape retina-wide organization of receptive fields}}, doi = {10.1038/s41593-023-01280-0}, volume = {26}, year = {2023}, } @misc{12370, abstract = {Statistics of natural scenes are not uniform - their structure varies dramatically from ground to sky. It remains unknown whether these non-uniformities are reflected in the large-scale organization of the early visual system and what benefits such adaptations would confer. Here, by relying on the efficient coding hypothesis, we predict that changes in the structure of receptive fields across visual space increase the efficiency of sensory coding. We show experimentally that, in agreement with our predictions, receptive fields of retinal ganglion cells change their shape along the dorsoventral retinal axis, with a marked surround asymmetry at the visual horizon. Our work demonstrates that, according to principles of efficient coding, the panoramic structure of natural scenes is exploited by the retina across space and cell-types. }, author = {Gupta, Divyansh and Sumser, Anton L and Jösch, Maximilian A}, publisher = {Institute of Science and Technology Austria}, title = {{Research Data for: Panoramic visual statistics shape retina-wide organization of receptive fields}}, doi = {10.15479/AT:ISTA:12370}, year = {2023}, } @article{12288, abstract = {To understand the function of neuronal circuits, it is crucial to disentangle the connectivity patterns within the network. However, most tools currently used to explore connectivity have low throughput, low selectivity, or limited accessibility. Here, we report the development of an improved packaging system for the production of the highly neurotropic RVdGenvA-CVS-N2c rabies viral vectors, yielding titers orders of magnitude higher with no background contamination, at a fraction of the production time, while preserving the efficiency of transsynaptic labeling. Along with the production pipeline, we developed suites of ‘starter’ AAV and bicistronic RVdG-CVS-N2c vectors, enabling retrograde labeling from a wide range of neuronal populations, tailored for diverse experimental requirements. We demonstrate the power and flexibility of the new system by uncovering hidden local and distal inhibitory connections in the mouse hippocampal formation and by imaging the functional properties of a cortical microcircuit across weeks. Our novel production pipeline provides a convenient approach to generate new rabies vectors, while our toolkit flexibly and efficiently expands the current capacity to label, manipulate and image the neuronal activity of interconnected neuronal circuits in vitro and in vivo.}, author = {Sumser, Anton L and Jösch, Maximilian A and Jonas, Peter M and Ben Simon, Yoav}, issn = {2050-084X}, journal = {eLife}, keywords = {General Immunology and Microbiology, General Biochemistry, Genetics and Molecular Biology, General Medicine, General Neuroscience}, publisher = {eLife Sciences Publications}, title = {{Fast, high-throughput production of improved rabies viral vectors for specific, efficient and versatile transsynaptic retrograde labeling}}, doi = {10.7554/elife.79848}, volume = {11}, year = {2022}, } @article{7551, abstract = {Novelty facilitates formation of memories. The detection of novelty and storage of contextual memories are both mediated by the hippocampus, yet the mechanisms that link these two functions remain to be defined. Dentate granule cells (GCs) of the dorsal hippocampus fire upon novelty exposure forming engrams of contextual memory. However, their key excitatory inputs from the entorhinal cortex are not responsive to novelty and are insufficient to make dorsal GCs fire reliably. Here we uncover a powerful glutamatergic pathway to dorsal GCs from ventral hippocampal mossy cells (MCs) that relays novelty, and is necessary and sufficient for driving dorsal GCs activation. Furthermore, manipulation of ventral MCs activity bidirectionally regulates novelty-induced contextual memory acquisition. Our results show that ventral MCs activity controls memory formation through an intra-hippocampal interaction mechanism gated by novelty.}, author = {Fredes Tolorza, Felipe A and Silva Sifuentes, Maria A and Koppensteiner, Peter and Kobayashi, Kenta and Jösch, Maximilian A and Shigemoto, Ryuichi}, journal = {Current Biology}, number = {1}, pages = {P25--38.E5}, publisher = {Elsevier}, title = {{Ventro-dorsal hippocampal pathway gates novelty-induced contextual memory formation}}, doi = {10.1016/j.cub.2020.09.074}, volume = {31}, year = {2021}, } @article{410, abstract = {Lesion verification and quantification is traditionally done via histological examination of sectioned brains, a time-consuming process that relies heavily on manual estimation. Such methods are particularly problematic in posterior cortical regions (e.g. visual cortex), where sectioning leads to significant damage and distortion of tissue. Even more challenging is the post hoc localization of micro-electrodes, which relies on the same techniques, suffers from similar drawbacks and requires even higher precision. Here, we propose a new, simple method for quantitative lesion characterization and electrode localization that is less labor-intensive and yields more detailed results than conventional methods. We leverage staining techniques standard in electron microscopy with the use of commodity micro-CT imaging. We stain whole rat and zebra finch brains in osmium tetroxide, embed these in resin and scan entire brains in a micro-CT machine. The scans result in 3D reconstructions of the brains with section thickness dependent on sample size (12–15 and 5–6 microns for rat and zebra finch respectively) that can be segmented manually or automatically. Because the method captures the entire intact brain volume, comparisons within and across studies are more tractable, and the extent of lesions and electrodes may be studied with higher accuracy than with current methods.}, author = {Masís, Javier and Mankus, David and Wolff, Steffen and Guitchounts, Grigori and Jösch, Maximilian A and Cox, David}, journal = {Scientific Reports}, number = {1}, publisher = {Nature Publishing Group}, title = {{A micro-CT-based method for quantitative brain lesion characterization and electrode localization}}, doi = {10.1038/s41598-018-23247-z}, volume = {8}, year = {2018}, } @article{62, abstract = {Imaging is a dominant strategy for data collection in neuroscience, yielding stacks of images that often scale to gigabytes of data for a single experiment. Machine learning algorithms from computer vision can serve as a pair of virtual eyes that tirelessly processes these images, automatically detecting and identifying microstructures. Unlike learning methods, our Flexible Learning-free Reconstruction of Imaged Neural volumes (FLoRIN) pipeline exploits structure-specific contextual clues and requires no training. This approach generalizes across different modalities, including serially-sectioned scanning electron microscopy (sSEM) of genetically labeled and contrast enhanced processes, spectral confocal reflectance (SCoRe) microscopy, and high-energy synchrotron X-ray microtomography (μCT) of large tissue volumes. We deploy the FLoRIN pipeline on newly published and novel mouse datasets, demonstrating the high biological fidelity of the pipeline’s reconstructions. FLoRIN reconstructions are of sufficient quality for preliminary biological study, for example examining the distribution and morphology of cells or extracting single axons from functional data. Compared to existing supervised learning methods, FLoRIN is one to two orders of magnitude faster and produces high-quality reconstructions that are tolerant to noise and artifacts, as is shown qualitatively and quantitatively.}, author = {Shabazi, Ali and Kinnison, Jeffery and Vescovi, Rafael and Du, Ming and Hill, Robert and Jösch, Maximilian A and Takeno, Marc and Zeng, Hongkui and Da Costa, Nuno and Grutzendler, Jaime and Kasthuri, Narayanan and Scheirer, Walter}, journal = {Scientific Reports}, number = {1}, publisher = {Nature Publishing Group}, title = {{Flexible learning-free segmentation and reconstruction of neural volumes}}, doi = {10.1038/s41598-018-32628-3}, volume = {8}, year = {2018}, } @article{6, abstract = {Lesion and electrode location verification are traditionally done via histological examination of stained brain slices, a time-consuming procedure that requires manual estimation. Here, we describe a simple, straightforward method for quantifying lesions and locating electrodes in the brain that is less laborious and yields more detailed results. Whole brains are stained with osmium tetroxide, embedded in resin, and imaged with a micro-CT scanner. The scans result in 3D digital volumes of the brains with resolutions and virtual section thicknesses dependent on the sample size (12-15 and 5-6 µm per voxel for rat and zebra finch brains, respectively). Surface and deep lesions can be characterized, and single tetrodes, tetrode arrays, electrolytic lesions, and silicon probes can also be localized. Free and proprietary software allows experimenters to examine the sample volume from any plane and segment the volume manually or automatically. Because this method generates whole brain volume, lesions and electrodes can be quantified to a much higher degree than in current methods, which will help standardize comparisons within and across studies.}, author = {Masís, Javier and Mankus, David and Wolff, Steffen and Guitchounts, Grigori and Jösch, Maximilian A and Cox, David}, journal = {Journal of visualized experiments}, publisher = {MyJove Corporation}, title = {{A micro-CT-based method for characterising lesions and locating electrodes in small animal brains}}, doi = {10.3791/58585}, volume = {141}, year = {2018}, } @article{740, abstract = {Developments in bioengineering and molecular biology have introduced a palette of genetically encoded probes for identification of specific cell populations in electron microscopy. These probes can be targeted to distinct cellular compartments, rendering them electron dense through a subsequent chemical reaction. These electron densities strongly increase the local contrast in samples prepared for electron microscopy, allowing three major advances in ultrastructural mapping of circuits: genetic identification of circuit components, targeted imaging of regions of interest and automated analysis of the tagged circuits. Together, the gains from these advances can decrease the time required for the analysis of targeted circuit motifs by over two orders of magnitude. These genetic encoded tags for electron microscopy promise to simplify the analysis of circuit motifs and become a central tool for structure‐function studies of synaptic connections in the brain. We review the current state‐of‐the‐art with an emphasis on connectomics, the quantitative analysis of neuronal structures and motifs.}, author = {Shigemoto, Ryuichi and Jösch, Maximilian A}, issn = {17597684}, journal = {WIREs Developmental Biology}, number = {6}, publisher = {Wiley-Blackwell}, title = {{The genetic encoded toolbox for electron microscopy and connectomics}}, doi = {10.1002/wdev.288}, volume = {6}, year = {2017}, } @article{1303, abstract = {In bright light, cone-photoreceptors are active and colour vision derives from a comparison of signals in cones with different visual pigments. This comparison begins in the retina, where certain retinal ganglion cells have 'colour-opponent' visual responses-excited by light of one colour and suppressed by another colour. In dim light, rod-photoreceptors are active, but colour vision is impossible because they all use the same visual pigment. Instead, the rod signals are thought to splice into retinal circuits at various points, in synergy with the cone signals. Here we report a new circuit for colour vision that challenges these expectations. A genetically identified type of mouse retinal ganglion cell called JAMB (J-RGC), was found to have colour-opponent responses, OFF to ultraviolet (UV) light and ON to green light. Although the mouse retina contains a green-sensitive cone, the ON response instead originates in rods. Rods and cones both contribute to the response over several decades of light intensity. Remarkably, the rod signal in this circuit is antagonistic to that from cones. For rodents, this UV-green channel may play a role in social communication, as suggested by spectral measurements from the environment. In the human retina, all of the components for this circuit exist as well, and its function can explain certain experiences of colour in dim lights, such as a 'blue shift' in twilight. The discovery of this genetically defined pathway will enable new targeted studies of colour processing in the brain.}, author = {Maximilian Jösch and Meister, Markus}, journal = {Nature}, number = {7598}, pages = {236 -- 239}, publisher = {Nature Publishing Group}, title = {{A neuronal circuit for colour vision based on rod-cone opponency}}, doi = {10.1038/nature17158}, volume = {532}, year = {2016}, } @article{1306, abstract = {Resolving patterns of synaptic connectivity in neural circuits currently requires serial section electron microscopy. However, complete circuit reconstruction is prohibitively slow and may not be necessary for many purposes such as comparing neuronal structure and connectivity among multiple animals. Here, we present an alternative strategy, targeted reconstruction of specific neuronal types. We used viral vectors to deliver peroxidase derivatives, which catalyze production of an electron-dense tracer, to genetically identify neurons, and developed a protocol that enhances the electron-density of the labeled cells while retaining the quality of the ultrastructure. The high contrast of the marked neurons enabled two innovations that speed data acquisition: targeted high-resolution reimaging of regions selected from rapidly-acquired lower resolution reconstruction, and an unsupervised segmentation algorithm. This pipeline reduces imaging and reconstruction times by two orders of magnitude, facilitating directed inquiry of circuit motifs.}, author = {Maximilian Jösch and Mankus, David and Yamagata, Masahito and Shahbazi, Ali and Schalek, Richard L and Suissa-Peleg, Adi and Meister, Markus and Lichtman, Jeff W and Scheirer, Walter J and Sanes, Joshua R}, journal = {eLife}, number = {2016JULY}, publisher = {eLife Sciences Publications}, title = {{Reconstruction of genetically identified neurons imaged by serial-section electron microscopy}}, doi = {10.7554/eLife.15015}, volume = {5}, year = {2016}, } @article{1304, abstract = {When confronted with a large-field stimulus rotating around the vertical body axis, flies display a following behavior called "optomotor response." As neural control elements, the large tangential horizontal system (HS) cells of the lobula plate have been prime candidates for long. Here, we applied optogenetic stimulation of HS cells to evaluate their behavioral role in Drosophila. To minimize interference of the optical activation of channelrhodopsin-2 with the visual perception of the flies, we used a bistable variant called ChR2-C128S. By applying pulses of blue and yellow light, we first demonstrate electrophysiologically that lobula plate tangential cells can be activated and deactivated repeatedly with no evident change in depolarization strength over trials. We next show that selective optogenetic activation of HS cells elicits robust yaw head movements and yaw turning responses in fixed and tethered flying flies, respectively.}, author = {Haikala, Väinö and Maximilian Jösch and Borst, Alexander and Mauss, Alex S}, journal = {Journal of Neuroscience}, number = {34}, pages = {13927 -- 13934}, publisher = {Society for Neuroscience}, title = {{Optogenetic control of fly optomotor responses}}, doi = {10.1523/JNEUROSCI.0340-13.2013}, volume = {33}, year = {2013}, } @article{1305, abstract = {In the fly Drosophila melanogaster, photoreceptor input to motion vision is split into two parallel pathways as represented by first-order interneurons L1 and L2 (Rister et al., 2007; Joesch et al., 2010). However, how these pathways are functionally specialized remains controversial. One study (Eichner et al., 2011) proposed that the L1-pathway evaluates only sequences of brightness increments (ON-ON), while the L2-pathway processes exclusively brightness decrements (OFF-OFF). Another study (Clark et al., 2011) proposed that each of the two pathways evaluates both ON-ON and OFF-OFF sequences. To decide between these alternatives, we recorded from motionsensitive neurons in flies in which the output from either L1 or L2 was genetically blocked. We found that blocking L1 abolishes ON-ON responses but leaves OFF-OFF responses intact. The opposite was true, when the output from L2 was blocked. We conclude that the L1 and L2 pathways are functionally specialized to detect ON-ON and OFF-OFF sequences, respectively.}, author = {Maximilian Jösch and Weber, Franz and Eichner, Hubert and Borst, Alexander}, journal = {Journal of Neuroscience}, number = {3}, pages = {902 -- 905}, publisher = {Society for Neuroscience}, title = {{Functional specialization of parallel motion detection circuits in the fly}}, doi = {10.1523/JNEUROSCI.3374-12.2013}, volume = {33}, year = {2013}, } @article{1299, abstract = {Recent experiments have shown that motion detection in Drosophila starts with splitting the visual input into two parallel channels encoding brightness increments (ON) or decrements (OFF). This suggests the existence of either two (ON-ON, OFF-OFF) or four (for all pairwise interactions) separate motion detectors. To decide between these possibilities, we stimulated flies using sequences of ON and OFF brightness pulses while recording from motion-sensitive tangential cells. We found direction-selective responses to sequences of same sign (ON-ON, OFF-OFF), but not of opposite sign (ON-OFF, OFF-ON), refuting the existence of four separate detectors. Based on further measurements, we propose a model that reproduces a variety of additional experimental data sets, including ones that were previously interpreted as support for four separate detectors. Our experiments and the derived model mark an important step in guiding further dissection of the fly motion detection circuit.}, author = {Eichner, Hubert and Maximilian Jösch and Schnell, Bettina and Reiff, Dierk F and Borst, Alexander}, journal = {Neuron}, number = {6}, pages = {1155 -- 1164}, publisher = {Elsevier}, title = {{Internal structure of the fly elementary motion detector}}, doi = {10.1016/j.neuron.2011.03.028}, volume = {70}, year = {2011}, } @article{1301, abstract = {Motion vision is essential for navigating through the environment. Due to its genetic amenability, the fruit fly Drosophila has been serving for a lengthy period as a model organism for studying optomotor behavior as elicited by large-field horizontal motion. However, the neurons underlying the control of this behavior have not been studied in Drosophila so far. Here we report the first whole cell recordings from three cells of the horizontal system (HSN, HSE, and HSS) in the lobula plate of Drosophila. All three HS cells are tuned to large-field horizontal motion in a direction-selective way; they become excited by front-to-back motion and inhibited by back-to-front motion in the ipsilateral field of view. The response properties of HS cells such as contrast and velocity dependence are in accordance with the correlation-type model of motion detection. Neurobiotin injection suggests extensive coupling among ipsilateral HS cells and additional coupling to tangential cells that have their dendrites in the contralateral hemisphere of the brain. This connectivity scheme accounts for the complex layout of their receptive fields and explains their sensitivity both to ipsilateral and to contralateral motion. Thus the main response properties of Drosophila HS cells are strikingly similar to the responses of their counterparts in the blowfly Calliphora, although we found substantial differences with respect to their dendritic structure and connectivity. This long-awaited functional characterization of HS cells in Drosophila provides the basis for the future dissection of optomotor behavior and the underlying neural circuitry by combining genetics, physiology, and behavior.}, author = {Schnell, Bettina and Jösch, Maximilian A and Förstner, Friedrich and Raghu, Shamprasad and Otsuna, Hideo and Ito, Kei and Borst, Alexander and Reiff, Dierk}, issn = {1522-1598}, journal = {Journal of Neurophysiology}, number = {3}, pages = {1646 -- 1657}, publisher = {American Physiological Society}, title = {{Processing of horizontal optic flow in three visual interneurons of the Drosophila brain}}, doi = {10.1152/jn.00950.2009}, volume = {103}, year = {2010}, } @article{1300, abstract = {Motion vision is a major function of all visual systems, yet the underlying neural mechanisms and circuits are still elusive. In the lamina, the first optic neuropile of Drosophila melanogaster, photoreceptor signals split into five parallel pathways, L1-L5. Here we examine how these pathways contribute to visual motion detection by combining genetic block and reconstitution of neural activity in different lamina cell types with whole-cell recordings from downstream motion-sensitive neurons. We find reduced responses to moving gratings if L1 or L2 is blocked; however, reconstitution of photoreceptor input to only L1 or L2 results in wild-type responses. Thus, the first experiment indicates the necessity of both pathways, whereas the second indicates sufficiency of each single pathway. This contradiction can be explained by electrical coupling between L1 and L2, allowing for activation of both pathways even when only one of them receives photoreceptor input. A fundamental difference between the L1 pathway and the L2 pathway is uncovered when blocking L1 or L2 output while presenting moving edges of positive (ON) or negative (OFF) contrast polarity: blocking L1 eliminates the response to moving ON edges, whereas blocking L2 eliminates the response to moving OFF edges. Thus, similar to the segregation of photoreceptor signals in ON and OFF bipolar cell pathways in the vertebrate retina, photoreceptor signals segregate into ON-L1 and OFF-L2 channels in the lamina of Drosophila.}, author = {Maximilian Jösch and Schnell, Bettina and Raghu, Shamprasad V and Reiff, Dierk F and Borst, Alexander}, journal = {Nature}, number = {7321}, pages = {300 -- 304}, publisher = {Nature Publishing Group}, title = {{ON and off pathways in Drosophila motion vision}}, doi = {10.1038/nature09545}, volume = {468}, year = {2010}, } @article{1302, abstract = {The nervous system of seeing animals derives information about optic flow in two subsequent steps. First, local motion vectors are calculated from moving retinal images, and second, the spatial distribution of these vectors is analyzed on the dendrites of large downstream neurons. In dipteran flies, this second step relies on a set of motion-sensitive lobula plate tangential cells (LPTCs), which have been studied in great detail in large fly species. Yet, studies on neurons that convey information to LPTCs and neuroanatomical investigations that enable a mechanistic understanding of the underlying dendritic computations in LPTCs are rare. We investigated the subcellular distribution of nicotinic acetylcholine receptors (nAChRs) on two sets of LPTCs: vertical system (VS) and horizontal system (HS) cells in Drosophila melanogaster. In this paper, we describe that both cell types express Dα7-type nAChR subunits specifically on higher order dendritic branches, similar to the expression of gamma aminobutyric acid (GABA) receptors. These findings support a model in which directional selectivity of LPTCs is achieved by the dendritic integration of excitatory, cholinergic, and inhibitory GABA-ergic input from local motion detectors with opposite preferred direction. Nonetheless, whole-cell recordings in mutant flies without Dα7 nAChRs revealed that direction selectivity of VS and HS cells is largely retained. In addition, mutant LPTCs were responsive to acetylcholine and remaining nAChR receptors were labeled by α-bungarotoxin. These results in LPTCs with genetically manipulated excitatory input synapses suggest a robust cellular implementation of dendritic processing that warrants direction selectivity. The underlying mechanism that ensures appropriate nAChR-mediated synaptic currents and the functional implications of separate sets or heteromultimeric nAChRs can now be addressed in this system.}, author = {Raghu, Shamprasad V and Maximilian Jösch and Sigrist, Stephan J and Borst, Alexander and Reiff, Dierk F}, journal = {Journal of Neurogenetics}, number = {1-2}, pages = {200 -- 209}, publisher = {Informa Healthcare}, title = {{Synaptic organization of lobula plate tangential cells in Drosophila: Dα7 cholinergic receptors}}, doi = {10.1080/01677060802471684}, volume = {23}, year = {2009}, } @article{1296, abstract = {The crystalline-like structure of the optic lobes of the fruit fly Drosophila melanogaster has made them a model system for the study of neuronal cell-fate determination, axonal path finding, and target selection. For functional studies, however, the small size of the constituting visual interneurons has so far presented a formidable barrier. We have overcome this problem by establishing in vivo whole-cell recordings [1] from genetically targeted visual interneurons of Drosophila. Here, we describe the response properties of six motion-sensitive large-field neurons in the lobula plate that form a network consisting of individually identifiable, directionally selective cells most sensitive to vertical image motion (VS cells [2, 3]). Individual VS cell responses to visual motion stimuli exhibit all the characteristics that are indicative of presynaptic input from elementary motion detectors of the correlation type [4, 5]. Different VS cells possess distinct receptive fields that are arranged sequentially along the eye's azimuth, corresponding to their characteristic cellular morphology and position within the retinotopically organized lobula plate. In addition, lateral connections between individual VS cells cause strongly overlapping receptive fields that are wider than expected from their dendritic input. Our results suggest that motion vision in different dipteran fly species is accomplished in similar circuitries and according to common algorithmic rules. The underlying neural mechanisms of population coding within the VS cell network and of elementary motion detection, respectively, can now be analyzed by the combination of electrophysiology and genetic intervention in Drosophila.}, author = {Maximilian Jösch and Plett, Johannes and Borst, Alexander and Reiff, Dierk F}, journal = {Current Biology}, number = {5}, pages = {368 -- 374}, publisher = {Cell Press}, title = {{Response properties of motion sensitive visual interneurons in the Lobula plate of Drosophila melanogaster}}, doi = {10.1016/j.cub.2008.02.022}, volume = {18}, year = {2008}, } @article{1297, abstract = {In flies, the large tangential cells of the lobula plate represent an important processing center for visual navigation based on optic flow. Although the visual response properties of these cells have been well studied in blowflies, information on their synaptic organization is mostly lacking. Here we study the distribution of presynaptic release and postsynaptic inhibitory sites in the same set of cells in Drosophila melanogaster. By making use of transgenic tools and immunohistochemistry, our results suggest that HS and VS cells of Drosophila express γ-aminobutyric acid (GABA) receptors in their dendritic region within the lobula plate, thus being postsynaptic to inhibitory input there. At their axon terminals in the protocerebrum, both cell types express synaptobrevin, suggesting the presence of presynaptic specializations there. HS- and VS-cell terminals additionally show evidence for postsynaptic GABAergic input, superimposed on this synaptic polarity. Our findings are in line with the general circuit for visual motion detection and receptive field properties as postulated from electrophysiological and optical recordings in blowflies, suggesting a similar functional organization of lobula plate tangential cells in the two species.}, author = {Raghu, Shamprasad V and Maximilian Jösch and Borst, Alexander and Reiff, Dierk F}, journal = {Journal of Comparative Neurology}, number = {4}, pages = {598 -- 610}, publisher = {Wiley-Blackwell}, title = {{Synaptic organization of lobula plate tangential cells in Drosophila: γ-aminobutyric acid receptors and chemical release sites}}, doi = {10.1002/cne.21319}, volume = {502}, year = {2007}, } @article{1298, abstract = {Genetically encoded fluorescent probes of neural activity represent new promising tools for systems neuroscience. Here, we present a comparative in vivo analysis of 10 different genetically encoded calcium indicators, as well as the pH-sensitive synapto-pHluorin. We analyzed their fluorescence changes in presynaptic boutons of the Drosophila larval neuromuscular junction. Robust neural activity did not result in any or noteworthy fluorescence changes when Flash-Pericam, Camgaroo-1, and Camgaroo-2 were expressed. However, calculated on the raw data, fractional fluorescence changes up to 18% were reported by synapto-pHluorin, Yellow Cameleon 2.0, 2.3, and 3.3, Inverse-Pericam, GCaMP1.3, GCaMP1.6, and the troponin C-based calcium sensor TN-L15. The response characteristics of all of these indicators differed considerably from each other, with GCaMP1.6 reporting high rates of neural activity with the largest and fastest fluorescence changes. However, GCaMP1.6 suffered from photobleaching, whereas the fluorescence signals of the double-chromophore indicators were in general smaller but more photostable and reproducible, with TN-L15 showing the fastest rise of the signals at lower activity rates. We show for GCaMP1.3 and YC3.3 that an expanded range of neural activity evoked fairly linear fluorescence changes and a corresponding linear increase in the signal-to-noise ratio (SNR). The expression level of the indicator biased the signal kinetics and SNR, whereas the signal amplitude was independent. The presented data will be useful for in vivo experiments with respect to the selection of an appropriate indicator, as well as for the correct interpretation of the optical signals.}, author = {Reiff, Dierk F and Ihring, Alexandra and Guerrero, Giovanna and Isacoff, Ehud Y and Maximilian Jösch and Nakai, Junichi and Borst, Alexander}, journal = {Journal of Neuroscience}, number = {19}, pages = {4766 -- 4778}, publisher = {Society for Neuroscience}, title = {{In vivo performance of genetically encoded indicators of neural activity in flies}}, doi = {10.1523/JNEUROSCI.4900-04.2005}, volume = {25}, year = {2005}, }