Biology subjects

Yan, C.

Publications and source records attributed to Yan, C..

111 records · Page 7Linked to original sources

bioRxiv2018

A compact head-mounted endoscope for in vivo calcium imaging in freely-behaving mice

Miniaturized fluorescence microscopes for imaging calcium transients are a promising tool for investigating the relationship between behaviour and population-level neuronal activity in rodents. However, commercially available miniature microscopes may be costly, and, because they are closed-source, may not be easily modified based on particular experimental requirements. Here, we describe how to build and use a low-cost compact head-mounted endoscope (CHEndoscope) system for in vivo calcium imaging. The CHEndoscope uses an implanted gradient index (GRIN) lens along with the genetically encoded calcium indicator GCaMP6 to image calcium transients from hundreds of neurons simultaneously in awake behaving mice. This system is affordable, open-source, and flexible, permitting modification depending on the particular experiment. This Unit describes in detail the assembly, surgical implantation, data collection, and processing of calcium signals using the CHEndoscope system. The aim of this open framework model is to provide an accessible set of miniaturized calcium imaging tools for the neuroscience research community.\n\nSignificance StatementThe ability to image calcium transients in awake, behaving rodents using miniature microscopes opens exciting and novel avenues for gaining insights into how information is encoded in neural circuits. The development of this tool has already had a significant impact on neuroscience research. The cost of commercial systems, however, may be prohibitive for many laboratories. Here, we describe an affordable, open-source compact head-mounted endoscope (CHEndoscope) system for performing in vivo calcium imaging in freely-behaving mice. CHEndoscopes may be manufactured by individual laboratories at relatively minor cost. Our hope is that greater availability of affordable, open-source tools (such as the one presented here) will accelerate the pace of discoveries in systems neuroscience.

neuroscience↗

bioRxiv2018

Microtubule acetylation is required for mechanosensation in Drosophila

At the cellular level, -tubulin acetylation alters the structure of microtubules to render them mechanically resistant to compressive forces. How this biochemical property of microtubule acetylation relates to mechanosensation remains unknown, though prior studies have shown that microtubule acetylation plays a role in touch perception. Here, we identify the major Drosophila -tubulin acetylase (dTAT) and show that it plays key roles in several forms of mechanosensation while exerting little effect on other sensory modalities. dTAT is highly expressed in neurons of the larval peripheral nervous system (PNS), but is not required for normal neuronal morphogenesis. We show that mutation of the acetylase gene or the K40 acetylation site in -tubulin impairs mechanical sensitivity in sensory neurons and behavioral responses to gentle touch, harsh touch, gravity, and sound stimulus, but not thermal stimulus. Finally, we show that dTAT is required for mechanically-induced activation of NOMPC, a microtubule-associated transient receptor potential channel, and functions to maintain integrity of the microtubule cytoskeleton in response to mechanical stimulation.

cell biology↗

bioRxiv2017

Genome-wide homology analysis reveals new insights into the origin of the wheat B genome

Wheat is a typical allopolyploid with three homoeologous subgenomes (A, B, and D). The ancestors of the subgenomes A and D had been identified, but not for the subgenome B. The goatgrass Aegilops speltoides (genome SS) has been controversially considered a candidate for the ancestor of the wheat B genome. However, the relationship of the Ae. speltoides S genome with the wheat B genome remains largely obscure, which has puzzled the wheat research community for nearly a century. In the present study, the genome-wide homology analysis identified perceptible homology between wheat chromosome 1B and Ae. speltoides chromosome 1S, but not between other chromosomes in the B and S genomes. An Ae. speltoides-originated segment spanning a genomic region of approximately 10.46 Mb was identified on the long arm of wheat chromosome 1B (1BL). The Ae. speltoides-originated segment on 1BL was found to co-evolve with the rest of the B genome in wheat species. Thereby, we conclude that Ae. speltoides had been involved in the origin of the wheat B genome, but should not be considered an exclusive ancestor of this genome. The wheat B genome might have a polyphyletic origin with multiple ancestors involved, including Ae. speltoides. These novel findings provide significant insights into the origin and evolution of the wheat B genome, and will facilitate polyploid genome studies in wheat and other plants as well.

genetics↗