A mouse for all reasons.

Cell (Impact Factor: 33.12). 02/2007; 128(1):9-13. DOI: 10.1016/j.cell.2006.12.018
Source: PubMed

ABSTRACT Three major mouse knockout programs are underway worldwide, working together to mutate all protein-encoding genes in the mouse using a combination of gene trapping and gene targeting in mouse embryonic stem (ES) cells. Although the current emphasis is on production of this valuable resource, there are significant efforts to facilitate program coordination, to enhance the availability of this resource, and to plan for future efforts in mouse genetics research.

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    ABSTRACT: Upon removal of culture conditions that maintain an undifferentiated state, mouse embryonic stem cells (ESCs) differentiate into various cell types. Differentiation can be facilitated by forced expression of certain transcription factors (TFs), each of which can generally specify a particular developmental lineage. We previously established 137 mouse ESC lines, each of which carried a doxycycline-controllable TF. Among them, Sox9 has unique capacity: its forced expression accelerates differentiation of mouse ESCs into cells of all three germ layers. With the additional use of specific culture conditions, overexpression of Sox9 facilitated the generation of endothelial cells, hepatocytes and neurons from ESCs. Furthermore, Sox9 action increases formation of p21 (WAF1/CIP1), which then binds to the SRR2 enhancer of pluripotency marker Sox2 and inhibits its expression. Knockdown of p21 abolishes inhibition of Sox2 and Sox9-accelerated differentiation, and reduction of Sox2 2 days after the beginning of ESC differentiation can comparably accelerate mouse ESC formation of cells of three germ layers. These data implicate the involvement of the p21-Sox2 pathway in the mechanism of accelerated ESC differentiation by Sox9 overexpression. The molecular cascade could be among the first steps to program ESC differentiation.
    Development 11/2014; 141(22):4254-66. DOI:10.1242/dev.115436 · 6.27 Impact Factor
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    H. Morgan, T. Beck, A. Blake, H. Gates, N. Adams, G. Debouzy, S. Leblanc, C. Lengger, H. Maier, D. Melvin, [......], D. Sunter, A. K. Gerdin, N. Igosheva, J. Estabel, S. Messager, N. Karp, C. Shannon, L. Roberson, C. Podrini, M. Lucas
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    ABSTRACT: A significant challenge facing high-throughput phenotyping of in-vivo knockout mice is ensuring phenotype calls are robust and reliable. Central to this problem is selecting an appropriate statistical analysis that models both the experimental design (the workflow and the way control mice are selected for comparison with knockout animals) and the sources of variation. Recently we proposed a mixed model suitable for small batch-oriented studies, where controls are not phenotyped concurrently with mutants. Here we evaluate this method both for its sensitivity to detect phenotypic effects and to control false positives, across a range of workflows used at mouse phenotyping centers. We found the sensitivity and control of false positives depend on the workflow. We show that the phenotypes in control mice fluctuate unexpectedly between batches and this can cause the false positive rate of phenotype calls to be inflated when only a small number of batches are tested, when the effect of knockout becomes confounded with temporal fluctuations in control mice. This effect was observed in both behavioural and physiological assays. Based on this analysis, we recommend two approaches (workflow and accompanying control strategy) and associated analyses, which would be robust, for use in high-throughput phenotyping pipelines. Our results show the importance in modelling all sources of variability in high-throughput phenotyping studies.
    PLoS ONE 10/2014; 9(10):e111239. DOI:10.1371/journal.pone.0111239 · 3.53 Impact Factor