Signaling mechanisms that detect stress and maintain homeostasis

项目摘要 布莱克威尔实验室主要研究维持新陈代谢、蛋白质和脂肪动态平衡的机制。 通过利用模式生物秀丽线虫的优势。我们的大部分工作涉及SKN-1，C. 秀丽的NRF(核因子-E2相关因子)转录因子的同源基因，它对氧化， 异源生物、蛋白酶体和某些代谢应激。NIGMS几乎支持了我们的努力 自1994年以来一直如此。在将SKN-1作为NRF蛋白质模型的开创性工作之后，我们已经证明 这些蛋白质在促进长寿方面起着重要作用，并阐明了一些有趣和保守的 他们职能的各个方面。除了一个单独的项目外，这个Mira涵盖了我们在SKN-1上的大部分工作 研究SKN-1A亚型(NRF1同源异构体)在脂质动态平衡中的特定功能。 在接下来的五年里，Mira的研究将解决一系列令人兴奋和相互关联的方面 SKN-1发挥作用，利用我们最近的发现提供的机会。已经很明显了，完全 描述两个主要的SKN-1亚型(SKN-1A和SKN-1C)的功能是至关重要的，并且将非常 信息量大，因为它们直接对应于具有不同功能和调节的NRF蛋白(NRF1和 NRF2)。为此，我们将产生必要的突变，并解决未得到满足的 确定SKN-1C在SKN-1至关重要的各种环境中的功能。我们已经确定，当 内质网(ER)受到二硫键交联损伤的应激，其反应是 与典型的内质网未折叠蛋白反应不同，显然是因为活性氧物种 世代被提升了。解释这一反应，我们将其命名为ER二硫化物中继反应 (DRRER)，并直接涉及SKN-1亚型，将对ER一个意想不到的方面产生新的见解 动态平衡。没有对应激反应的分析研究它们对宇宙氧化还原体的影响。 氧化修饰的半胱氨酸残基和氧化还原调节过程。最近绘制了线虫的地图 氧化还原酶在史无前例的报道中，我们将从而阐明DRRER和SKN-1的氧化还原效应 异构体。这一努力将揭示应激反应效应的新维度，确定受制于 氧化还原调节，并揭示活性氧物种可能意外增加的过程 寿命。这些方法将有助于理解抗压性或寿命有多大 任何干预措施都会增加。因此，我们还将研究抑制主生长调节剂的影响 MTORC1(雷帕霉素的机械靶点)。线虫为无偏见的遗传提供了无与伦比的系统 对压力防御机制的研究，我们将在未来五年内继续采取这一方法 重点研究蛋白酶体应激如何调节SKN-1A。这些努力将产生生物学的新范式 调节，并显著加深我们对细胞和有机体如何抵御压力的理解。

Project Summary The Blackwell lab studies mechanisms that maintain metabolic, protein, and lipid homeostasis, primarily by leveraging the advantages of the model organism C. elegans. Much of our work involves SKN-1, the C. elegans ortholog of the NRF (NF-E2-related factor) transcription factors, which respond to oxidative, xenobiotic, proteasomal, and certain metabolic stresses. NIGMS has supported our efforts almost continuously since 1994. Having pioneered work on SKN-1 as an NRF protein model, we have shown that these proteins play important roles in promoting longevity and elucidated a number of intriguing and conserved aspects of their functions. This MIRA covers the majority of our work on SKN-1, aside from a separate project investigating specific functions of the SKN-1A isoform (NRF1 ortholog) in lipid homeostasis. During the next five years this MIRA research will address a set of exciting and interrelated aspects of SKN-1 functions, building upon opportunities provided by our recent findings. It has become clear that fully delineating the functions of the two major SKN-1 isoforms (SKN-1A and SKN-1C) is critical and will be very informative because they correspond directly to NRF proteins with distinct functions and regulation (NRF1 and NRF2, respectively). To this end, we will generate necessary mutations and address the unmet need of identifying SKN-1C functions in a variety of contexts where skn-1 is critical. We have determined that when the endoplasmic reticulum (ER) is subject to stress from impairment of disulfide crosslinking the response is distinct from the canonical ER unfolded protein response, apparently because reactive oxygen species generation is elevated. Elucidating this response, which we have named the ER disulfide relay response (DRRER), and which involves SKN-1 isoforms directly, will yield new insights into an unanticipated aspect of ER homeostasis. No analyses of stress responses have investigated their effects on the redoxome, the universe of oxidatively modified Cys residues and redox-regulated processes. Having recently mapped the C. elegans redoxome at unprecedented coverage, we will thereby elucidate the redox effects of the DRRER and SKN-1 isoforms. This effort will reveal a new dimension of stress response effects, identify mechanisms subject to redox regulation, and uncover processes through which reactive oxygen species can unexpectedly increase lifespan. These approaches will be informative for understanding how stress resistance or lifespan can be increased by any intervention. We will thereby also investigate effects of inhibiting the master growth regulator mTORC1 (mechanistic target of rapamycin). C. elegans provides an unparalleled system for unbiased genetic investigation of stress defense mechanisms, an approach we will continue during the next five years by focusing on how proteasomal stress regulates SKN-1A. These efforts will yield new paradigms of biological regulation and significantly deepen our understanding of how cells and organisms defend against stress.