A Systems Approach to Understanding Effects of MCHM on Cellular Metabolism

 描述（由申请人提供）：在理解外源性碳氢化合物如何干扰对多效性药物反应（PDR）至关重要的关键信号传导途径和对细胞信号传导至关重要的其他关键生化途径方面存在根本性差距。这种知识差距的持续存在是一个重要的问题，因为有些人暴露于4-甲基环己烷甲醇（MCHM），并立即出现无法解释的健康问题。长期的健康问题是具有挑战性的预测没有获得这些信息。长期目标是鉴定响应于有毒化学物质介导表型变异的蛋白质，以便可以建立对环境应激源敏感性增加的个体（酵母和人类）基因型的预测因子。本申请的目的是确定受MCHM影响的细胞途径。使用酿酒酵母作为模式生物，暴露于MCHM激活了多效性药物反应，并下调了负责制造第二信使的生物合成途径。中心假设是亚致死MCHM暴露将改变细胞途径，包括肌醇和PDR途径。这一假设是根据初步数据表明，S。与未暴露的细胞相比，暴露于MCHM的酿酒酵母的生长显著滞后。这个建议的理由是，确定MCHM的细胞效应将提供一个机制为基础的框架，随后详细研究MCHM对人类健康的影响和进一步的实验与热带爪蟾。提出了以下具体目标：1。确定受MCHM影响的细胞途径和降解MCHM所需的细胞途径。评估Med 15变异对MCHM反应的影响。在第一个目标下，我们将监测对MCHM具有不同反应的酵母中细胞活力和转录记忆的变化。在第二个具体目标下，重点将是Med 15内的遗传变异如何改变MCHM的转录和表型反应，Med 15是一种重要的多态性转录调节因子，分别通过RNA-seq和蛋白质组学测量。在申请人看来，所提出的研究是创新的，因为它通过使用系统方法（包括遗传学、转录组学和蛋白质组学）评估遗传多样性酵母菌株中的细胞应答，代表了与现状的实质性背离。这一贡献将是重要的，因为它将直接提供基础，以确定长期影响的MCHM暴露的基本细胞功能的模式生物。反过来，这可能有助于了解MCHM和其他结构相似但研究不足的化学品对人类健康的潜在长期影响。

 DESCRIPTION (provided by applicant): There is a fundamental gap in understanding how exogenous hydrocarbons can interfere with key signaling pathways critical for pleiotropic drug response (PDR) and other critical biochemical pathways important for cellular signal ling. Persistence of this gap in knowledge represent an important problem because some people were exposed to 4-methylcyclohexane methanol (MCHM) and had immediate unexplained health problems. Long-term health problems are challenging to predict without obtaining this information. The long- term goal is to identify proteins that mediate phenotypic variation in response to toxic chemicals so that predictors of genotypes of individuals, both yeast and humans, with increased sensitivity to environmental stressors can be established. The objective in this application is to determine cellular pathways that are affected by MCHM. Using Saccharomyces cerevisiae as a model organism, exposure to MCHM activated the pleiotropic drug response and down-regulated biosynthetic pathways responsible for making second messengers. The central hypothesis is that sub-lethal MCHM exposure will alter cellular pathways including the inositol and PDR pathways. This hypothesis was formulated based on preliminary data showing that S. cerevisiae exposed to MCHM significantly lagged in growth in comparison to unexposed cells. The rationale for this proposal is that a determination of the cellular effects of MCHM will provide a mechanism-based framework for subsequent detailed studies on MCHM's health effects in humans and further experiments with Xenopus tropicalis. The following specific aims are proposed: 1. Determine cellular pathways affected by MCHM and required for degradation of MCHM and 2. Assess the impact of variation in Med15 on MCHM response. Under the first aim we will monitor changes in cellular viability and transcriptional memory across yeast with different responses to MCHM. Under the second specific aim the focus will be on how genetic variation within Med15, an important and polymorphic transcriptional regulator changes the transcriptional and phenotypic response to MCHM measured by RNA-seq and proteomics respectively. The proposed research is innovative, in the applicant's opinion, because it represents a substantive departure from the status quo by assessing cellular responses using a systems approach including genetic, transcriptomic, and proteomic in genetically diverse yeast strains. This contribution will be significant because it will directly provide the foundation for determination of long-term effects f MCHM exposure on basic cellular function in a model organisms. In turn, this is likely to contribute to an understanding of potential human health long-term effects due to MCHM and other structurally similar but also understudied chemicals.