Mechanism of action of Retinal Determination proteins

翻译后摘要：视网膜血管系统的适当发展是必不可少的视力。 此外，异常血管生长的疾病，如糖尿病视网膜病变，年龄 相关性黄斑变性和早产儿视网膜病变是 失明视网膜决定（RD）级联是一个进化保守的 在蝇眼发育的背景下最好的研究信号通路，包括 眼睛缺失（EYA）和正弦眼同源框（SIX）家族的蛋白质。我们有 最近证明，眼睛缺席在血管发育中起着重要作用。 我们现在有证据表明SIX家族的转录因子在机制上 与EYA协同作用，巨噬细胞和内皮细胞中的SIX蛋白 细胞参与调节血管生成。此竞争性更新应用程序构建 基于这些观察，专门测试了SIX蛋白在发育中的作用， 和病理性视网膜血管生成。我们假设视网膜髓样细胞中的SIX 1 上调VEGFC表达，从而促进尖至茎转化， 邻近视网膜血管系统的病变。内皮细胞中的SIX 1/2促进 在小管形成过程中的分支和增殖以及上调VEGFC 表达，从而加强了尖到茎的转换。为了在体外验证这一假设 在体内，我们提出了以下具体目的：（一）阐明的作用， 巨噬细胞SIX 1在调节视网膜血管生成，和（II）阐明的作用， 内皮细胞SIX 1/2在视网膜血管生成中的作用。每个目标都将通过整合 多种技术，包括机械生物化学，基于细胞培养的测定， 化学生物学和眼睛发育和疾病的动物模型。 本案无关该项目的具体成果将包括：（1）划定 调节视网膜血管生成的机制，（2）鉴定和 分子表征的途径，可以针对治疗效益， 增殖性视网膜病变，和（3）验证铅小分子抑制剂， 可以进一步发展为靶向治疗。

Abstract: Appropriate development of the retinal vasculature is essential for vision. Moreover, abnormal blood vessel growth in diseases such as diabetic retinopathy, age related macular degeneration and retinopathy of prematurity are common causes of blindness. The Retinal Determination (RD) cascade is an evolutionarily conserved signaling pathway best studied in the context of fly eye development and includes proteins of the Eyes Absent (EYA) and Sine oculis homeobox (SIX) families. We have recently demonstrated that Eyes Absent plays an essential role in vascular development. We now have evidence that the SIX family of transcription factors mechanistically synergize with EYA, and that the SIX proteins in both macrophages and in endothelial cells participate in regulating angiogenesis. This competing renewal application builds upon these observations to specifically test the role of the SIX proteins in developmental and pathological retinal angiogenesis. We hypothesize that SIX1 in retinal myeloid cells upregulates VEGFC expression and thus promotes tip-to-stalk conversion and anastomoses in the adjacent retinal vasculature. SIX1/2 in endothelial cells promotes branching and proliferation during tubulogenesis as well as upregulating VEGFC expression, thus reinforcing the tip-to-stalk conversion. To test this hypothesis in vitro and in vivo we propose the following Specific Aims: (I) To elucidate the role of macrophage SIX1 in regulating retinal angiogenesis, and (II) To elucidate the role of endothelial SIX1/2 in retinal angiogenesis. Each aim will be accomplished by integrating diverse techniques including mechanistic biochemistry, cell culture based assays, chemical biology and animal models of eye development and disease. RELEVANCE. The tangible outcomes of this project will include (1) the delineation of mechanisms by which retinal angiogenesis is regulated, (2) the identification and molecular characterization of a pathway that could be targeted for therapeutic benefit in proliferative retinopathies, and (3) the validation of lead small molecule inhibitors that could be further developed as targeted therapeutics.