Kim William Y, Safran Michal, Buckley Marshall R M, Ebert Benjamin L, Glickman Jonathan, Bosenberg Marcus, Regan Meredith, Kaelin William G
Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
EMBO J. 2006 Oct 4;25(19):4650-62. doi: 10.1038/sj.emboj.7601300. Epub 2006 Sep 14.
Many functions have been assigned to the von Hippel-Lindau tumor suppressor gene product (pVHL), including targeting the alpha subunits of the heterodimeric transcription factor HIF (hypoxia-inducible factor) for destruction. The binding of pVHL to HIFalpha requires that HIFalpha be hydroxylated on one of two prolyl residues. We introduced HIF1alpha and HIF2alpha variants that cannot be hydroxylated on these sites into the ubiquitously expressed ROSA26 locus along with a Lox-stop-Lox cassette that renders their expression Cre-dependent. Expression of the HIF2alpha variant in the skin and liver induced changes that were highly similar to those seen when pVHL is lost in these organs. Dual expression of the HIF1alpha and HIF2alpha variants in liver, however, more closely phenocopied the changes seen after pVHL inactivation than did the HIF2alpha variant alone. Moreover, gene expression profiling confirmed that the genes regulated by HIF1alpha and HIF2alpha in the liver are overlapping but non-identical. Therefore, the pathological changes caused by pVHL inactivation in skin and liver are due largely to dysregulation of HIF target genes.
许多功能已被赋予冯·希佩尔-林道肿瘤抑制基因产物（pVHL），包括靶向异二聚体转录因子HIF（缺氧诱导因子）的α亚基进行降解。pVHL与HIFα的结合要求HIFα在两个脯氨酰残基之一上被羟基化。我们将在这些位点不能被羟基化的HIF1α和HIF2α变体引入到普遍表达的ROSA26位点，并带有一个使其表达依赖于Cre的Lox-stop-Lox盒。皮肤和肝脏中HIF2α变体的表达诱导了与这些器官中pVHL缺失时所见高度相似的变化。然而，肝脏中HIF1α和HIF2α变体的双重表达比单独的HIF2α变体更接近地模拟了pVHL失活后所见的变化。此外，基因表达谱分析证实，肝脏中由HIF1α和HIF2α调节的基因是重叠但不相同的。因此，皮肤和肝脏中pVHL失活引起的病理变化主要是由于HIF靶基因的失调。
