Klotho Regulation and Aging

项目摘要 我们研究的重点是研究衰老抑制蛋白Klotho是如何随着衰老而调节的。 在大脑里。当Klotho的表达被消除时，小鼠发育正常，但死亡年龄为4岁 几个月大的孩子。这种快速恶化伴随着一种与观察到的相似的表型。 老年人(认知障碍、动脉粥样硬化、异位钙化、肺气肿、 骨质疏松症、皮肤萎缩和脱发、胸腺退化、不育和骨矿物质减少 密度)。Klotho在小鼠体内的消除导致认知障碍，与增加 氧化应激。相比之下，Klotho过度表达转基因小鼠的寿命延长了30%，而且 能抵抗氧化应激。我们的研究小组发现Klotho在衰老的非人类中表达下调 灵长类动物、大鼠和小鼠的大脑，这些都使我们假设Klotho是重要的 大脑功能及其随年龄的下调可能是氧化应激的结果，如果 预防，可以改善衰退为神经退行性疾病。工作提出，审查 Klotho启动子和3‘非编码区随年龄的调节及氧化损伤对细胞的影响 Klotho促进剂随年龄增长。我们将确定Klotho启动子的高GC含量是否 使其成为与年龄相关的下调监管的目标，因为随着时间的推移，损害会累积 因为氧化应激。这将通过比较Klotho的氧化状态来完成 在体外和老年恒河猴死后标本中对其他基因的启动子 大脑。我们还将致力于鉴定结合和诱导激活的转录因子 Klotho促进者。Klotho启动子不包含经典转录元件 入会仪式。了解哪些因素对Klotho转录很重要可能有助于揭示 导致Klotho激活的信号通路以及Klotho在正常细胞中的作用。最后，我们会 确定Klotho是否受microRNAs(MiR)调节，以及miR在大脑中如何变化 年龄。MIR结合并调节mRNA的翻译，关于miR是否以及如何翻译尚不清楚 影响Klotho加工。再说一次，了解调节Klotho的过程将使我们能够 更好地了解影响Klotho和Klotho在细胞中更广泛作用的过程 功能。这项工作的结果将增加关于抗衰老基因Klotho和 阐明氧化损伤如何选择性下调特定基因的可能机制。

Project Abstract The focus of our study is to examine how the age suppressor protein, Klotho, is regulated with aging in the brain. When Klotho expression is eliminated, mice develop normally, but age to death by 4 months of age. This rapid deterioration is accompanied with a phenotype not unlike what is observed in aged humans (cognitive impairment, atherosclerosis, ectopic calcification, emphysema, osteoporosis, skin atrophy and hair loss, thymic involution, infertility and decreased bone mineral density). Elimination of Klotho in mice causes cognitive impairment that is associated with increased oxidative stress. In contrast, Klotho overexpressing transgenic mice live longer by up to 30% and are resistant to oxidative stress. Our group found that Klotho is downregulated in the aging non-human primate, rat and mouse brains Together, these have lead us to hypothesize that Klotho is important in brain function and its downregulation with age may be the result of oxidative stress which, if prevented, could ameliorate decline into neurodegenerative disease. The work proposed, examines regulation of the Klotho promoter and 3'UTR with age and the effect of oxidative damage to the Klotho promoter with age. We will determine whether the high GC content of the Klotho promoter makes it a target for age-related downregulation because of damage that accumulates over time because of oxidative stress. This will be done by comparing the oxidation state of the Klotho promoter to that of other genes both in vitro and in post mortem samples from aged rhesus monkey brain. We will also work to characterize the transcription factors that bind and induce activation of the Klotho promoter. The Klotho promoter does not contain the classical elements for transcription initiation. Understanding what factors are important for Klotho transcription may shed light on signaling pathways leading to Klotho activation and the role of Klotho in the normal cell. Last, we will determine whether Klotho is regulated by microRNAs (miR) and how miR change in the brain with age. MiR bind and regulate translation of mRNA and nothing is known about whether and how miR affect Klotho processing. Again, understanding the processes that regulate Klotho will enable us to have a better understanding of the processes that affect Klotho and Klotho's wider role in cellular function. The results of this work will add new knowledge on both the anti-aging gene Klotho and elucidate a possible mechanism for how oxidative damage selectively downregulates specific genes.