Lifespan and healthspan regulation by hypoxic response transcription factor HIF-1

缺氧反应转录因子 HIF-1 对寿命和健康的调节

• 批准号: 8441592
• 负责人: MATT KAEBERLEIN
• 金额: $ 29.88万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8441592
• 关键词: Age; Aging; Animals; Biological Assay; Caenorhabditis elegans; Cell Nucleus; Disease; Family; Gene Expression; Gene Targeting; Genes; Goals; Growth; Health; Human; Hypoxia; Insulin; Intervention; Journals; Lead; Life; Longevity; Longevity Pathway; Malignant Neoplasms; Mammals; Mass Spectrum Analysis; Measures; Messenger RNA; Nematoda; Oxygen; Pathway interactions; Pigments; Plasmids; Play; Post-Translational Protein Processing; Proteins; Publications; Publishing; RNA Interference; Regulation; Reporting; Resistance; Role; Science; Series; Signal Transduction; Specificity; System; Temperature; Testing; Toxic effect; Transgenic Animals; Work; age related; base; cell type; chromatin immunoprecipitation; dietary restriction; fluorescent age pigment; human disease; knock-down; novel; overexpression; polyglutamine; promoter; public health relevance; response; therapeutic target; transcription factor; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): We recently identified the hypoxic response transcription factor, HIF-1, as a novel modifier of longevity and healthspan in Caenorhabditis elegans. In a study published in the journal Science, we showed that stabilization of HIF-1 by inhibiting its proteasomal degradation under normoxic conditions increases life span through a mechanism that is genetically distinct from dietary restriction and reduced insulin-like signaling, a finding that has since been independently replicated by two groups. We also showed that growth of wild type animals under hypoxia, which is sufficient to stabilize and activate HIF-1, also increases life span. Following publication of our study, the Kapahi lab reported that loss of HIF-1 increases life span under their experimental conditions. We have since determined that stabilization of HIF-1 increases life span in a temperature- independent manner, while loss of HIF-1 increases life span in a temperature-dependent manner. Unlike life span extension from activation of HIF-1 in normoxia, life span extension from deletion of HIF-1 or hypoxia requires the FOXO-family transcription factor DAF-16. Here we propose to further define the mechanisms by which HIF-1 modulates longevity and healthspan in C. elegans, both as a pro- and anti-longevity factor. In Specific Aim 1, we will (1) further define the experimental conditions under which deletion of HIF-1 can increase life span and determine whether healthspan is also extended under these conditions, (2) test the hypothesis that DAF-16 is activated by loss of HIF-1 or by hypoxia using chromatin immunoprecipitation to determine whether DAF-16 is localized to known or novel target genes, and (3) determine how DAF-16 becomes relocalized to the nucleus in response to loss of HIF-1 or hypoxia by using mass spectrometry to quantify known and novel post-translational modifications of DAF-16 in response to these interventions. In specific Aim 2, we will (1) use RNAi knock-down mRNAs that are differentially expressed in response to stabilization of HIF-1 to identify the downstream targets of HIF-1 that are involved in life span and healthspan extension when HIF-1 is stabilized under normoxic conditions and (2) determine whether these genes play a role in modulating longevity in response to other known longevity pathways. In specific Aim 3, we will determine which cell types are involved in modulating life span and healthspan extension from stabilization of HIF-1 under normoxic conditions by generating transgenic animals expressing either (1) the VHL-1 E3 ligase which targets HIF-1 for degradation or (2) a non-degradable form of HIF-1 under promoters with known cell- type specificities and quantifying the resulting effects on longevity and measures of healthspan. HIF-1 and the hypoxic response are highly conserved from nematodes to humans and have been implicated in human diseases, most notably a variety of cancers. Thus, a better understanding of the dual role that HIF-1 can play as a modifier of life span and healthspan in nematodes will lead to new hypotheses that can be directly tested in mammals, and is likely to be directly relevant to human health and age-related disease.

描述（由申请人提供）：我们最近将低氧反应转录因子HIF-1确定为秀丽隐杆线虫的新长寿和健康范围的新修饰符。在《科学杂志》上发表的一项研究中，我们表明，通过在常氧条件下抑制其蛋白酶体降解来稳定HIF-1，通过一种机制通过一种与饮食限制和胰岛素样信号降低的机制来增加寿命，这一发现自此被两组独立地复制。我们还表明，在缺氧下野生型动物的生长足以稳定和激活HIF-1，这也会增加寿命。在我们的研究发表后，卡帕希实验室报告说，在实验条件下，HIF-1的损失会增加寿命。此后，我们确定HIF-1的稳定以独立温度的方式增加寿命，而HIF-1的损失以温度依赖性方式增加了寿命。与HIF-1在Normoxia中激活的寿命延伸不同，HIF-1或缺氧的寿命延长需要FOXO家庭转录因子DAF-16。在这里，我们建议进一步定义HIF-1在秀丽隐杆线虫中调节寿命和健康范围的机制，无论是秀丽隐杆线虫中的寿命还是抗隆格因子。在特定目标1中，（1）将进一步定义HIF-1缺失可以增加寿命的实验条件，并确定在这些条件下还延长了健康范围，（2）测试假设DAF-16通过损失HIF-1或通过低氧使用染色质素免疫注射来激活DAF-16是否在DAF-16中局部化的靶标生成或新颖的靶标的Genes和3），并且（3）通过使用质谱法量化DAF-16的已知和新型翻译后修饰，响应于这些干预措施，核心响应HIF-1或缺氧的损失。在特定目标2中，我们将使用（1）使用RNAi敲低mRNA，这些mRNA响应于HIF-1的稳定而差异表达，以识别HIF-1的下游靶标在寿命跨度和HealthSpan扩展中涉及HIF-1时，当HIF-1在常态氧气条件下稳定时，并且（2）（2）确定这些基因在模块化的longevity pathity pathity pathity pathity pathity pathity pathity pathity中是否起着作用。在特定目标3中，我们将通过产生表达型（1）靶向HIF-1的转基因动物来调节HIF-1在常氧条件下稳定HIF-1的延伸而涉及哪些细胞类型，该动物靶向HIF-1用于降解的HIF-1，或者（2）在已知的细胞中效果和量化构成型号的HIF-1在不可分类的情况下进行了延伸和量化的效果，并构成了量的特定效果。 HIF-1和低氧反应是从线虫对人的高度保守，并且与人类疾病有关，最著名的是各种癌症。因此，对HIF-1可以作为生命跨度的修饰和HealthSpan在线虫中发挥的双重作用的更好理解将导致可以直接在哺乳动物中进行直接检验的新假设，并且可能与人类健康和与年龄相关的疾病直接相关。