The role of HIF prolyl hydroxylase-2 (PHD2) during physiological and pathological processes in mice

根据目前的提议，我想申请额外的第六届艾美奖诺特年。理由是，除了最近的几篇论文外，我们的主要研究成果目前要么正在高影响因子期刊上进行审查，要么几乎准备提交。此外，基于我的小组的研究表现，血液学系（TU德累斯顿）已承诺与我申请海森堡教授在未来。因此，我认为这第六个E. N。这一年将是一个极好的机会，可以发表我们的成果，完成其他有前途的研究路线，并获得教授资格。在过去的4.5年里，我们小组的研究一直集中在小鼠氧传感器的作用上。这些蛋白质在所有生物中都不可或缺，因为它使细胞能够立即适应不适当的pO2。这种机制主要依赖于HIF-脯氨酰羟化酶（PHD1 - 3），羟化缺氧诱导因子（HIF）并导致其失活的酶。使用不同的遗传方法，我们发现PHD 2在红细胞量的控制、皮肤伤口愈合和造血干细胞（HSC）的维持过程中至关重要（Franke et al.，审查中）。使用一种新的条件性PHD2缺陷小鼠系（CD68：cre-PHD2f/f），我们发现HSC隔室中PHD2的缺失以HIF 1a依赖性方式诱导多能祖细胞（MPP）和HSC的自我更新。在这个额外的E. N研究年中，我们希望扩大这些发现。虽然我们发现了HSC中PHD2和HIF 1a之间的直接联系，但我们建议在严重压力下对最不成熟的造血细胞进行基因分析。我们相信，这将使我们能够找到参与PHD2相关抑制HSC分化和维持其多能性的相关基因。我们的发现对血液系统恶性肿瘤也有重要意义。因此，我们计划使用我们的Vav：cre-PHD2f/f小鼠（仅在造血系统中缺乏PHD2）在新开发的急性髓性白血病小鼠模型（AML）中研究PHD2-HIF 1角。在急性结肠炎模型中，我们发现CD68：cre-PHD2f/f小鼠比WT小鼠更易感。现在，密集的研究表明，PHD2-缺陷的结肠上皮细胞是负责这种敏感性，虽然独立的羟基化活性。在这额外的一年里，我们希望进行一些非常明确的离体实验，这将有助于我们找到负责的途径（例如TGF β，NF κ B......）。在我们小组最近的癌症研究出版物中，我们详细描述了PHD2在肿瘤发展过程中的作用。我们现在还发现，骨髓和T细胞中PHD2的缺失可以控制肿瘤生长。使用遗传诱导的肿瘤模型（MMTV-pyMT-cre-PHD2f/f），我们将扩展这些发现，以在临床相关模型中寻找PHD2在肿瘤发展期间在炎性细胞中的作用。

With the current proposal I would like to apply for an additional 6th Emmy Noether year. The reasoning is that apart from several recent publications, our main research results are currently either under review in a high impact factor journal or almost ready to be submitted. Moreover, based on the research performance of my group, the department of hematology (TU Dresden) has committed itself to apply with me for a Heisenberg professorship in the future. Therefore, I believe that this 6th E.N. year would be an excellent opportunity to publish our results, finalize other promising research lines and get qualified for a professorship. During the last 4.5 years, research in our group has been focused on the role of oxygen-sensors in mice. These proteins are indispensable in all living beings as it enables the cells to instantaneously adapt to inappropriate pO2. This machinery mainly relies on the HIF-prolyl hydroxylases (PHD1-3), enzymes that hydroxylate hypoxia inducible factor (HIF) and lead to their inactivation. Using different genetic approach we found that PHD2 is of utmost importance during the control of red blood cell mass, skin wound healing and maintenance of hematopoietic stem cells (HSCs) (Franke et al., under review). Using a new conditional PHD2 deficient mouse line (CD68:cre-PHD2f/f) we showed that loss of PHD2 in the HSC compartment induces self-renewal of multipotent progenitors (MPP) and HSCs in a HIF1a-dependent manner. During this additional E.N research year we want to expand these findings. Although we found a direct link between PHD2 and HIF1a in HSCs, we propose to perform gene profiling on the most immature hematopoietic cells under severe stress. We are convinced that this will enable us to find the responsible genes involved in PHD2-related inhibition of differentiation in HSCs and maintaining of their multipotency. Our findings have also important implications with regard to hematological malignancies. We therefore plan to study the PHD2-HIF1 angle in a newly developed acute myeloid leukemia mouse model (AML) using our Vav:cre-PHD2f/f mice; deficient for PHD2 only in the hematopoietic system. In an acute colitis model we found that CD68:cre-PHD2f/f mice are much more susceptible than their WT counterparts. Intense research has now demonstrated that PHD2-deficiency in colon epithelial cells is responsible for this sensitivity although independent of their hydroxylation activity. During this extra year we want to perform some very defined ex vivo experiments that will help us to find the responsible pathway (e.g. TGFbeta, NFkB…). In a recent Cancer Research publication from our group we described in detail the role of PHD2 during tumor development. We now also found that loss of PHD2 in myeloid and T-cells can control tumor growth. Using genetically induced tumor models (MMTV-pyMT-cre-PHD2f/f) we will expand these findings in search of the role of PHD2 in inflammatory cells during tumor development in a clinically relevant model.