Machka C, Kersten M, Zobawa M, Harder A, Horsch M, Halder T, Lottspeich F, Hrabé de Angelis M, Beckers J
Institute of Experimental Genetics, GSF-National Research Center, Ingolstädter Landstr.1, 85764 Neuherberg, Germany.
Gene Expr Patterns. 2005 Dec;6(1):94-101. doi: 10.1016/j.modgep.2005.04.009. Epub 2005 Jun 23.
The Notch signaling pathway has pleiotropic functions during mammalian embryogenesis. It is required for the patterning and differentiation of the presomitic and somitic paraxial mesoderm and of the neural tube. We used DNA-chip expression profiling and 2D-gel electrophoresis combined with peptide mass fingerprinting to identify genes and proteins differentially regulated in E10.5 Dll1 (delta-like 1, Delta1) mutant embryos. The differential expression profiling approach identified 47 regulated transcripts and 40 differentially expressed proteins. The majority of these genes has until now not been associated with Notch signaling. Subsequent whole-mount in situ hybridization confirmed that a subset of the identified transcripts has restricted and distinct patterns of expression in E10.5 mouse embryos. For most genes these expression patterns were affected in the presomitic mesoderm, in differentiating somites of Dll1 mutant embryos and in the neural tube and cells differentiating from it. Similar effects were observed in embryos homozygous for the Headturner (Htu) and pudgy (pu) mutations, which are alleles of the Notch ligands Jag1 and Dll3. The regulated expression of a subset of the proteins was validated by immunoblots. Remarkably six of the proteins down-regulated in Dll1 mutant embryos are proteasome subunits. The large set of regulated genes identified in this differential expression profiling approach is an important resource for further functional studies.
Notch信号通路在哺乳动物胚胎发育过程中具有多效性功能。它对于前体节和体节的轴旁中胚层以及神经管的模式形成和分化是必需的。我们使用DNA芯片表达谱分析以及二维凝胶电泳结合肽质量指纹图谱技术，来鉴定在E10.5 Dll1（δ样1，Delta1）突变胚胎中差异调节的基因和蛋白质。差异表达谱分析方法鉴定出47个受调节的转录本和40种差异表达的蛋白质。到目前为止，这些基因中的大多数尚未与Notch信号传导相关联。随后的全胚胎原位杂交证实，所鉴定的转录本中的一个子集在E10.5小鼠胚胎中具有受限且独特的表达模式。对于大多数基因而言，这些表达模式在Dll1突变胚胎的前体节中胚层、分化的体节、神经管及其分化的细胞中均受到影响。在Headturner（Htu）和矮胖（pu）突变的纯合胚胎中也观察到了类似的效应，这两个突变是Notch配体Jag1和Dll3的等位基因。通过免疫印迹验证了一部分蛋白质的调节表达。值得注意的是，在Dll1突变胚胎中下调的六种蛋白质是蛋白酶体亚基。在这种差异表达谱分析方法中鉴定出的大量受调节基因是进一步功能研究的重要资源。
