Engrailed-2 regulates genes related to vesicle formation and transport in cerebellar Purkinje cells

Engrailed transcription factors regulate survival, cell fate decisions and axon pathfinding in central neurons. En-2 can also attenuate Purkinje cell (PC) maturation. Here, we use array analysis to scrutinize gene expression in developing PCs overexpressing Engrailed-2 (L7En-2). The majority (70%) of regulated genes was found down-regulated in L7En-2 cerebella, consistent with the known repressive function of Engrailed-2. Differential gene expression, verified by in situ hybridization or Western blotting, was particularly evident during the first postnatal week, when L7En-2 PCs display conspicuous deficits in dendritogenesis. Functional classification revealed clusters of genes linked to vesicle formation and transport. Consistently, Golgi stacks located at the axonal pole of wild type PC somata were rarely detected in L7En-2 PCs. In addition, long continuous stretches of endoplasmic reticulum typically found around the axonal pole of wild type PCs were less frequently observed in transgenic cells. Engrailed-2 might therefore orchestrate PC survival and process formation as a regulator of subcellular organization

In-Tube Extraction-GC-MS as a High-Capacity Enrichment Technique for the Analysis of Alcoholic Beverages

An in-tube extraction (ITEX) method for the GC-MS analysis of volatile constituents of alcoholic beverages was developed and applied in the analysis of 46 beers from six varieties, Alt, Helles, Kölsch, Pilsener beer, Schwarzbier, and wheat beer, which are popular in Germany. The extraction performance of nine different sorbent materials was evaluated. The best overall sensitivity was achieved using Tenax TA, with method detection limits down to 0.01 μg L^–1, whereas the widest linear range was possible with PDMS, covering almost 5 orders of magnitude. This is the first application of PDMS in ITEX as a high-capacity extraction device and highlights the importance of choosing the appropriate sorbent material for the analytical task at hand. A satisfying chemometric discrimination of all analyzed beer varieties was possible, and alcohol-free beers could clearly be separated from regular beers, also