Adolf Butenandt Institute, Center for Integrated Protein Science (CIPSM), Ludwig Maximilian University, Munich, Germany.
Mol Cell Biol. 2012 Jul;32(13):2359-71. doi: 10.1128/MCB.06619-11. Epub 2012 Apr 16.
ISWI is an evolutionarily conserved ATPase that catalyzes nucleosome remodeling in different macromolecular complexes. Two mammalian ISWI orthologs, SNF2H and SNF2L, are thought to have specialized functions despite their high sequence similarity. To date, the function of SNF2L in human cells has not been a focus of research. Newly established specific monoclonal antibodies and selective RNA interference protocols have now enabled a comprehensive characterization of loss-of-function phenotypes in human cells. In contrast to earlier results, we found SNF2L to be broadly expressed in primary human tissues. Depletion of SNF2L in HeLa cells led to enhanced proliferation and increased migration. These phenomena were explained by transcriptome profiling, which identified SNF2L as a modulator of the Wnt signaling network. The cumulative effects of SNF2L depletion on gene expression portray the cell in a state of activated Wnt signaling characterized by increased proliferation and chemotactic locomotion. Accordingly, high levels of SNF2L expression in normal melanocytes contrast with undetectable expression in malignant melanoma. In summary, our data document an inverse relationship between SNF2L expression and features characteristic of malignant cells.
ISWI 是一种进化上保守的 ATP 酶,能够在不同的大分子复合物中催化核小体重塑。两种哺乳动物的 ISWI 同源物,SNF2H 和 SNF2L,尽管它们具有高度的序列相似性,但被认为具有专门的功能。迄今为止,SNF2L 在人类细胞中的功能尚未成为研究的重点。新建立的特异性单克隆抗体和选择性 RNA 干扰方案现在使人们能够全面描述人类细胞中功能丧失表型。与早期的结果相反,我们发现 SNF2L 在原发性人组织中广泛表达。在 HeLa 细胞中耗尽 SNF2L 会导致增殖增强和迁移增加。这些现象通过转录组谱分析得到了解释,该分析鉴定 SNF2L 是 Wnt 信号网络的调节剂。SNF2L 耗竭对基因表达的累积效应将细胞描绘成激活的 Wnt 信号状态,其特征是增殖和趋化性运动增加。因此,正常黑素细胞中 SNF2L 的高表达与恶性黑色素瘤中无法检测到的表达形成对比。总之,我们的数据记录了 SNF2L 表达与恶性细胞特征之间的反比关系。