Du Roure Camille, Versavel Aude, Doll Thierry, Cao Chun, Pillonel Vincent, Matthias Gabriele, Kaller Markus, Spetz Jean-François, Kopp Patrick, Kohler Hubertus, Müller Matthias, Matthias Patrick
Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.
Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland; Faculty of Sciences, University of Basel, Basel, Switzerland.
PLoS One. 2014 Apr 18;9(4):e92836. doi: 10.1371/journal.pone.0092836. eCollection 2014.
We have identified expression of the gene encoding the transcriptional coactivator FOG-1 (Friend of GATA-1; Zfpm1, Zinc finger protein multitype 1) in B lymphocytes. We found that FOG-1 expression is directly or indirectly dependent on the B cell-specific coactivator OBF-1 and that it is modulated during B cell development: expression is observed in early but not in late stages of B cell development. To directly test in vivo the role of FOG-1 in B lymphocytes, we developed a novel embryonic stem cell recombination system. For this, we combined homologous recombination with the FLP recombinase activity to rapidly generate embryonic stem cell lines carrying a Cre-inducible transgene at the Rosa26 locus. Using this system, we successfully generated transgenic mice where FOG-1 is conditionally overexpressed in mature B-cells or in the entire hematopoietic system. While overexpression of FOG-1 in B cells did not significantly affect B cell development or function, we found that enforced expression of FOG-1 throughout all hematopoietic lineages led to a reduction in the number of circulating eosinophils, confirming and extending to mammals the known function of FOG-1 in this lineage.
我们已经确定了转录共激活因子FOG-1（GATA-1的朋友；Zfpm1，锌指蛋白多类型1）编码基因在B淋巴细胞中的表达。我们发现FOG-1的表达直接或间接依赖于B细胞特异性共激活因子OBF-1，并且在B细胞发育过程中受到调节：在B细胞发育的早期阶段可观察到表达，而在晚期阶段则没有。为了直接在体内测试FOG-1在B淋巴细胞中的作用，我们开发了一种新型的胚胎干细胞重组系统。为此，我们将同源重组与FLP重组酶活性相结合，以快速生成在Rosa26位点携带Cre诱导转基因的胚胎干细胞系。利用该系统，我们成功地培育出了转基因小鼠，其中FOG-1在成熟B细胞或整个造血系统中被条件性过表达。虽然FOG-1在B细胞中的过表达并没有显著影响B细胞的发育或功能，但我们发现，在所有造血谱系中强制表达FOG-1会导致循环嗜酸性粒细胞数量减少，这证实并将FOG-1在该谱系中的已知功能扩展到了哺乳动物。
