Recombinant adeno-associated virus (rAAV) vector-mediated gene transfer into genetically defined neuron subtypes has become a powerful tool to study the neuroanatomy of neuronal circuits in the brain and to unravel their functions. More recently, this methodology has also become popular for the analysis of spinal cord circuits. To date, a variety of naturally occurring AAV serotypes and genetically modified capsid variants are available but transduction efficiency in spinal neurons, target selectivity, and the ability for retrograde tracing are only incompletely characterized. Here, we have compared the transduction efficiency of seven commonly used AAV serotypes after intraspinal injection. We specifically analyzed local transduction of different types of dorsal horn neurons, and retrograde transduction of dorsal root ganglia (DRG) neurons and of neurons in the rostral ventromedial medulla (RVM) and the somatosensory cortex (S1). Our results show that most of the tested rAAV vectors have similar transduction efficiency in spinal neurons. All serotypes analyzed were also able to transduce DRG neurons and descending RVM and S1 neurons via their spinal axon terminals. When comparing the commonly used rAAV serotypes to the recently developed serotype 2 capsid variant rAAV2retro, a > 20-fold increase in transduction efficiency of descending supraspinal neurons was observed. Conversely, transgene expression in retrogradely transduced neurons was strongly reduced when the human synapsin 1 (hSyn1) promoter was used instead of the strong ubiquitous hybrid cytomegalovirus enhancer/chicken β-actin promoter (CAG) or cytomegalovirus (CMV) promoter fragments. We conclude that the use of AAV2retro greatly increases transduction of neurons connected to the spinal cord via their axon terminals, while the hSyn1 promoter can be used to minimize transgene expression in retrogradely connected neurons of the DRG or brainstem. Cover Image for this issue: doi. 10.1111/jnc.13813.
It is an open source image processing Java program designed for scientific multidimensional images. This open platform for scientific image analysis is used in life sciences.
Image J has been transformed to ImageJ2 application.
This new application improves ImageJ data engine to be sufficient to analyze modern datasets and makes the addition of new functionality possible and provides a framework for interoperability between a plethora of external image visualization and analysis programs.
ImageJ2 strengthens ImageJ’s utility by: 1) generalizing the ImageJ data model; 2) introducing a robust architecture instrumental in building bridges across a range of other image processing tools; 3) remaining open source and cross-platform with permissive licensing, enabling continued widespread adoption and extension; 4) building on the huge collection of existing ImageJ plugins while enabling the creation of new plugins with more powerful features; and 5) leveraging a correspondingly large and diverse community to foster a collaborative and interdisciplinary project that facilitates the collective advancement of science.
A non-profit plasmid repository dedicated to helping scientists around the world share high-quality plasmids. They work with laboratories to assemble a high-quality library of published and useful plasmids and their associated cloning/sequence data for use in research and discovery. By linking plasmids with articles, scientists can always find data related to the materials they request. There is no cost to deposit plasmids to Addgene and it will store samples in triplicate (including one at an offsite backup facility), sequence key regions for validation, and handle the appropriate Material Transfer Agreements (MTAs) with institutions. Additionally, users can create a webpage that directs scientists to request plasmids. Material Transfer Agreements (MTAs) allow open exchange to occur because they offer intellectual property and liability protection for material providers. Institutions that have deposited materials at Addgene require a MTA for each transfer of material.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to SciCrunch, however this is not currently a free service.