Nutrient Sensing and Hexokinases in T. brucei

布氏锥虫的营养感应和己糖激酶

基本信息

批准号：
8229951
负责人：
JAMES Culvin MORRIS
金额：
$ 36.01万
依托单位：
CLEMSON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-01 至 2016-01-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Glucose metabolism is the sole source of ATP for the infectious lifecycle stage of the African trypanosome, Trypanosoma brucei. Mis-regulation of the first enzyme in the pathway, hexokinase, is toxic to the parasite. However, little is known concerning the regulatory mechanisms that modulate expression of the two genes that encode this essential enzyme activity. The goal of this application is to identify the mechanisms the parasite employs to regulate hexokinases at the gene expression and enzyme activity levels in response to distinct environmental conditions. Preliminary data indicates the trypanosome hexokinases are dynamically regulated in response to environmental glucose levels through mechanisms that include both modulation of transcript steady-state abundance and expression, as well as changes in enzyme oligomer composition. Regulation of transcript abundance in the African trypanosome occurs primarily via post-transcriptional mechanisms as a result of information encoded in gene 3'UTRs. Elements that influence hexokinase steady-state transcript abundance will be identified by monitoring transcript levels of a reporter gene construct harboring a series of mutated hexokinase 3'UTRs. The impact of these constructs on gene expression will also be considered by scoring enzyme activity of the reporter gene. At the protein level, hexokinase hexamer composition, which the parasite can alter based on growth conditions, influences enzyme activity, including sensitivity to regulatory molecules. To understand the differences in sensitivity to regulatory molecules, site-directed mutagenesis will be used to identify domains and residues required for inhibitor binding. The impact of variants that are engineered to no longer be susceptible to regulation in vitro will be assessed in vivo by expression in T. brucei. Through the characterization of regulatory mechanisms required for hexokinase expression, new means of targeting glucose metabolism, a required parasite pathway, will be identified. PUBLIC HEALTH RELEVANCE: The proposed research is important to public health as mechanisms identified here will yield new targets for desperately needed therapeutic development for the African trypanosome while expanding our understanding of the fundamental cellular process of glucose sensing, topics that are supported by the mission of the NIH.

描述（由申请人提供）：葡萄糖代谢是非洲锥虫锥虫Brucei的传染性生命周期阶段ATP的唯一来源。途径中第一种酶的错误调节，己糖酶对寄生虫有毒。然而，关于调节这两个基因表达的调节机制，几乎没有人知道编码这种基本酶活性的表达。该应用的目的是确定寄生虫采用的机制在基因表达和酶活性水平下对不同环境条件进行调节的己糖酶。初步数据表明，锥虫六动物酶通过机制对环境葡萄糖水平进行动态调节，包括调节转录本稳态丰度和表达，以及酶低聚物组成的变化。非洲锥虫中转录物丰度的调节主要是由于基因3'UTRS中编码的信息而导致的转录后机制。影响己糖酶稳态转录物丰度的元素将通过监测具有一系列突变的己糖酶3'UTR的记者基因构建体的转录水平来识别。这些构建体对基因表达的影响也将通过评分报告基因的酶活性来考虑。在蛋白质水平上，寄生虫可以根据生长条件改变己糖酶六聚体组成，会影响酶活性，包括对调节分子的敏感性。为了了解对调节分子的敏感性的差异，将使用位置定向的诱变来识别抑制剂结合所需的域和残基。设计为不再容易受到体外调节的变体的影响将通过T. Brucei的表达在体内评估。通过表征己糖酶表达所需的调节机制，将确定靶向葡萄糖代谢的新方法，即所需的寄生虫途径。公共卫生相关性：拟议的研究对公共卫生很重要，因为此处确定的机制将为非洲锥虫迫切需要的治疗发展带来新的目标，同时扩大了我们对葡萄糖感应的基本细胞的理解，这是由受到受主题的支持，这些主题得到了受到的主题的支持。 NIH。

项目成果

期刊论文数量（13）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Quercetin, a fluorescent bioflavanoid, inhibits Trypanosoma brucei hexokinase 1.

DOI：
10.1016/j.exppara.2010.10.011
发表时间：
2011-02
期刊：
EXPERIMENTAL PARASITOLOGY
影响因子：
2.1
作者：
Dodson, Heidi C.;Lyda, Todd A.;Chambers, Jeremy W.;Morris, Meredith T.;Christensen, Kenneth A.;Morris, James C.
通讯作者：
Morris, James C.

Peptide-targeted delivery of a pH sensor for quantitative measurements of intraglycosomal pH in live Trypanosoma brucei.

DOI：
10.1021/bi400029m
发表时间：
2013-05-28
期刊：
Biochemistry
影响因子：
2.9
作者：
Lin S;Morris MT;Ackroyd PC;Morris JC;Christensen KA
通讯作者：
Christensen KA

Extra-glycosomal localisation of Trypanosoma brucei hexokinase 2.

DOI：
10.1016/j.ijpara.2012.02.008
发表时间：
2012-04
期刊：
International journal for parasitology
影响因子：
4
作者：
Joice AC;Lyda TL;Sayce AC;Verplaetse E;Morris MT;Michels PA;Robinson DR;Morris JC
通讯作者：
Morris JC

Antiparasitic lethality of sulfonamidebenzamides in kinetoplastids.

磺酰胺苯甲酰胺在动质体中的抗寄生虫致死作用。

DOI：
10.1016/j.bmcl.2017.01.043
发表时间：
2017
期刊：
Bioorganic & medicinal chemistry letters
影响因子：
2.7
作者：
Hackler,Amber;Patrick,StephenL;Kahney,ElizabethW;Flaherty,DanielP;Sharlow,ElizabethR;Morris,JamesC;Golden,JenniferE
通讯作者：
Golden,JenniferE

Glycolysis in the african trypanosome: targeting enzymes and their subcellular compartments for therapeutic development.