Cell adhesion molecule DM-GRASP presented in different nanopatterns to neurons regulates attachment and neurite growth

Adhesion and neurite formation of neurons and neuroblastoma cells critically depends on the lateral spacing of the cell adhesion molecule DM-GRASP offered as nanostructured substrate

Confocal light sheet microscopy: micron-scale neuroanatomy of the entire mouse brain

Elucidating the neural pathways that underlie brain function is one of the greatest challenges in neuroscience. Light sheet based microscopy is a cutting edge method to map cerebral circuitry through optical sectioning of cleared mouse brains. However, the image contrast provided by this method is not sufficient to resolve and reconstruct the entire neuronal network. Here we combined the advantages of light sheet illumination and confocal slit detection to increase the image contrast in real time, with a frame rate of 10 Hz. In fact, in confocal light sheet microscopy (CLSM), the out-of-focus and scattered light is filtered out before detection, without multiple acquisitions or any post-processing of the acquired data. The background rejection capabilities of CLSM were validated in cleared mouse brains by comparison with a structured illumination approach. We show that CLSM allows reconstructing macroscopic brain volumes with sub-cellular resolution. We obtained a comprehensive map of Purkinje cells in the cerebellum of L7-GFP transgenic mice. Further, we were able to trace neuronal projections across brain of thy1-GFP-M transgenic mice. The whole-brain high-resolution fluorescence imaging assured by CLSM may represent a powerful tool to navigate the brain through neuronal pathways. Although this work is focused on brain imaging, the macro-scale high-resolution tomographies affordable with CLSM are ideally suited to explore, at micron-scale resolution, the anatomy of different specimens like murine organs, embryos or flies. (C) 2012 Optical Society of Americ

<i>Prdm6</i> deficiency results in embryonic lethality.

<p>(<b>A</b>) <i>Prdm6</i>^wt/del mice were intercrossed. Pregnant mice were euthanized and embryos dissected and genotyped at defined developmental stages. The percentages of viable embryos of the respective genotypes at the different stages of embryonic development (dpc = days post coitum) are indicated; wild type <i>Prdm6</i>^wt/wt (wt/wt) and heterozygous <i>Prdm6</i>^wt/del (wt/del) mice are viable, whereas <i>Prdm6</i>-deficient <i>Prdm6</i>^{<i>del/del</i>} (del/del) embryos begin to die after E10.0, with no <i>Prdm6</i>^{<i>del/del</i>} embryos being found at developmental stages beyond E16.0. (<b>B</b>) Northern blot analysis of <i>Prdm6</i> expression using total embryonic RNA from different developmental stages from wild type embryos. <i>Gapdh</i> expression analysis served as a loading control. (<b>C</b>) Representative wild type control and <i>Prdm6</i>-deficient embryos (del/del) at the indicated developmental stages. White arrows indicate edematous swelling. (<b>D</b>) Transverse heart sections from wild type control and <i>Prdm6</i>-deficient embryos were stained with H&E and analyzed by microscopy. The thin myocardium of <i>Prdm6</i>-deficient embryos (del/del) is indicated by an arrow. Scale bars correspond to 200 µm. </p