Sivagnanam, S. | bioRxiv Science

bioRxiv2018

Open Source Brain: a collaborative resource for visualizing, analyzing, simulating and developing standardized models of neurons and circuits

Computational models are powerful tools for investigating brain function in health and disease. However, biologically detailed neuronal and circuit models are complex and implemented in a range of specialized languages, making them inaccessible and opaque to many neuroscientists. This has limited critical evaluation of models by the scientific community and impeded their refinement and widespread adoption. To address this, we have combined advances in standardizing models, open source software development and web technologies to develop Open Source Brain, a platform for visualizing, simulating, disseminating and collaboratively developing standardized models of neurons and circuits from a range of brain regions. Model structure and parameters can be visualized and their dynamical properties explored through browser-controlled simulations, without writing code. Open Source Brain makes neural models transparent and accessible and facilitates testing, critical evaluation and refinement, thereby helping to improve the accuracy and reproducibility of models, and their dissemination to the wider community.

neuroscience↗

bioRxiv2017

An adaptable chromosome preparation methodology for use in invertebrate research organisms

BackgroundThe ability to efficiently visualize and manipulate chromosomes is fundamental to understand the genetic architecture of organisms. This can be challenging for many invertebrates because conventional chromosome preparation protocols deal primarily hypotonic conditions tailored for use with vertebrates and rely extensively on cultured cells which are rarely available for invertebrates. Hence, a simple and inexpensive chromosome preparation protocol, adaptable to multiple invertebrate model species is needed.\n\nResultsWe optimized a chromosome preparation protocol and applied it to several planarian species (Phylum: Platyhelminthes), the freshwater apple snail Pomacea canaliculata (Phylum: Mollusca), and the starlet sea anemone Nematostella vectensis (Phylum: Cnidaria). We showed that both mitotically active adult tissues and embryos can be used as sources of metaphase chromosomes, expanding the potential use of this technique to invertebrates lacking cell lines and/or with limited access to the complete life cycle. Simple hypotonic treatment with DI water was sufficient for karyotyping. The karyotypes we obtained allowed the identification of differences in ploidy and chromosome architecture among otherwise morphologically indistinguishable organisms, as in the case of a mixed population of planarians collected in the wild. Furthermore, we showed that in all tested organisms representing three different phyla, this protocol can be effectively coupled with downstream applications, such as chromosome fluorescent in situ hybridization.\n\nConclusionThe simple and inexpensive chromosome preparation protocol reported here can be readily adapted to new invertebrate research organisms in order to expand and accelerate the discovery of new biology in understudied branches of the tree of life.

developmental biology↗