Microarrays - The Challenge of Preparing Brain Tissue Samples

Department of Pharmacological Science and Experimental Medicine, University of Camerino, 62032 Camerino, Italy.
Addiction Biology (Impact Factor: 5.36). 04/2005; 10(1):5-13. DOI: 10.1080/13556210412331327803
Source: PubMed


Microarray experiments allow researchers to collect an amazing amount of gene expression data that have the potential to provide unique information to help interpretation of the biological functions of the central nervous system. These experiments are, however, technically demanding and present unique difficulties when used in the context of neuroscience research, in particular. Success or failure of microarray experiments are highly dependent on reproducible target preparations. This involves a relatively long chain of preparation steps, such as removal of tissue from experimental animals or from post-mortem human brains, storage, selection, and excision of brain regions. This is followed by RNA extraction, reverse transcription, and labeling of target cDNAs or cRNAs. Additionally, it is emphasized that the quality of microarray data largely relies on the proper handling of animals throughout experiments and the time of the day when experiments are stopped. This article tries to provide hints for some basic rules to be observed in preparation of samples for expression profiling studies.

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    05/2014; 2(1):53. DOI:10.1186/2051-5960-2-53
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    • "Data analysis, using dual selection criteria (moderated t-test, p < 0.05 (Limma) and fold change ± 1.15), identified temporally distinct sAPPα-induced patterns of expression (Figure 2A), a subset of which was confirmed by quantitative PCR (qPCR; Figure 3 and see Additional file 2: Tables S1-S4). The majority of genes were modestly changed (fold change: -2.9 to 3.2), an effect particular to neurobiological tissue [27] and consistent with previous studies [24,28-30]. Interestingly, two thirds (66%) of differentially expressed genes were upregulated in the 15 min dataset, while the majority of differentially expressed genes were downregulated at 2 h (59%) and 24 h (79%) (Figure 2A), suggesting that there is a relatively rapid onset homeostatic control of gene expression. "
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    PLoS ONE 03/2011; 6(3):e17840. DOI:10.1371/journal.pone.0017840 · 3.23 Impact Factor
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