Rab GTPases of Entamoeba histolytica
溶组织内阿米巴的 Rab GTP 酶
基本信息
- 批准号:6839520
- 负责人:
- 金额:$ 17.5万
- 依托单位:
- 依托单位国家:美国
- 项目类别:
- 财政年份:2001
- 资助国家:美国
- 起止时间:2001-02-01 至 2007-01-31
- 项目状态:已结题
- 来源:
- 关键词:
项目摘要
DESCRIPTION: The enteric protozoan parasite, Entamoeba histolytica, infects 10
percent of the world's population, leading to 50 million cases of invasive
amebiasis and 100,000 deaths annually. Vaccines or chemoprophylactic agents,
which can protect residents of endemic areas or travelers, are not available.
Infection is acquired by ingestion of the cyst form, followed by excystation of
amoeboid trophozoites, which migrate to and colonize the bowel lumen. The
endosomal and lysosomal (endo-lysosomal (EL)) system of Entamoeba appears to
play a role in its pathogenesis as (I) uptake and digestion of nutrients, (ii)
invasion of the intestinal epithelium, and (iii) dissemination and
establishment of extra-intestinal infections, including liver abscess, rely on
endocytosis and the action of hydrolytic enzymes and pore-forming proteins
secreted from the pathogen. Despite its importance, little is known about the
molecular factors goveming the Entamoeba EL system, including associated
proteins which may regulate EL functions. Such proteins may be candidates for
vaccine development.
Three genes have been isolated from an E. histo!ytica cDNA library encoding a
protein (EhRabl 1) that is 56 percent identical in amino acid sequence to human
Rabi 1, a protein (EhRab7) that is 56 percent identical in amino acid sequence
to human Rab7, and a protein that is a novel member (EhRabA) of the Rab family
of GlPases; Rab GTPases are known to regulate vesicular trafficking. EhRabl 1
is enriched in magnetically purified early endosomes of Entamoeba and EhRabA
and EhRab7are enriched in magnetically purified early and late endosomes of
Enfamoeba. The subcellular localization of these Rab GTPases suggests that they
play a role in EL function of E. histolytica. To test this hypothesis, the
following aims are proposed. In Specific Aim I the subcetlular location of the
EhRabs will be refined using immunofluorescence and immunoelectron microscopy
of Entamoeba trophozoites. In Specific Aim 2 the role of the EhRabs in EL
function and pathogenicity will be addressed. Genetically engineered Entamoeba
cell lines overexpressing dominant inhibitory and constitutively active
versions of the EhRabs will be generated. In addition, Entamoeba cell lines
expressing anisense transcripts of the EhRabs (to reduce the cellular levels of
the EhRab) will be generated. EL processes will be examined in these strains,
including pinocytosis of fluid phase and phagocytosis of large particles,
maintenance of intra-endosomal pH, and secretion of hydrolases. In addiion, the
virulence of these genetically altered strains will be assessed by measuring
their ability to (i) carry out contact-mediated cell lysis of Chinese Hamster
Ovary cells, (ii) release pore-forming peptides responsible for the
disintegration of host cell membranes (iii) correctly localize an important
adherence molecule to the cell surface and, (iv) establish liver abscess in the
SCID mouse model. To gain further insight into how EhRabs function, in Specific
Aim 3, Entamoeba proteins that interact with the EhRabs will be identified by
yeast two-hybrid screening and affinity chromatography. These studies represent
the first examination of the role of Rab GiPases of Entamoeba in EL function
and pathogenicity and will significantly advance the field by contributing to
the understanding of how vesicles and proteins are trafficked in this pathogen.
描述:肠道原生动物寄生虫,溶组织内阿米巴,感染10
占世界人口的50%,导致5000万例侵入性
每年有10万人死于阿米巴病。疫苗或化学预防剂,
可以保护流行区居民或旅行者的疫苗。
感染是通过摄入囊肿形式获得的,随后是
阿米巴滋养体,迁移到肠腔并定殖。的
内阿米巴的内体和溶酶体(内-溶酶体(EL))系统似乎
在其发病机制中发挥作用,如(I)营养物质的吸收和消化,(ii)
肠上皮的侵袭,和(iii)传播和
包括肝脓肿在内的肠外感染的建立依赖于
内吞作用以及水解酶和成孔蛋白的作用
从病原体中分泌出来尽管它的重要性,很少有人知道,
控制内阿米巴EL系统的分子因素,包括相关的
可能调节EL功能的蛋白质。这些蛋白质可能是候选者,
疫苗研发。
从一株E. histo!一个编码
蛋白质(EhRabl 1),其氨基酸序列与人类相同56%
Rabi 1,一种氨基酸序列有56%相同的蛋白质(EhRab 7)
人Rab 7,以及Rab家族的新成员(EhRabA)的蛋白质
已知Rab GTP酶调节囊泡运输。EhRabl 1
富含磁性纯化的内阿米巴和EhRabA的早期内体
和EhRab 7富集在磁性纯化的早期和晚期内体中,
阿米巴原虫这些Rab GTP酶的亚细胞定位表明,
在E.溶组织剂为了验证这一假设,
提出了以下目标。在特定目标I中,
将使用免疫荧光和免疫电子显微镜对EhRab进行精制
内阿米巴滋养体在具体目标2中,EhRabs在EL中的作用
功能和致病性。基因工程内阿米巴
过表达显性抑制和组成型活性的细胞系
将生成EhRab的版本。此外,内阿米巴细胞系
表达EhRab的异义转录物(以降低EhRab的细胞水平)。
EhRab)将被生成。将在这些菌株中检查EL过程,
包括液相的胞饮作用和大颗粒的吞噬作用,
维持内体pH和分泌水解酶。此外,
这些基因改变的菌株的毒力将通过测量
它们(i)进行接触介导的中国仓鼠细胞裂解的能力
卵巢细胞,(ii)释放孔形成肽负责
宿主细胞膜的解体(iii)正确定位重要的
粘附分子的细胞表面和,(iv)建立肝脓肿,
SCID小鼠模型。为了进一步了解EhRabs的功能,具体来说,
目的3、通过免疫荧光法鉴定与EhRab相互作用的内阿米巴蛋白。
酵母双杂交筛选和亲和层析。这些研究代表了
内阿米巴Rab Gipases在EL功能中作用的初步研究
和致病性,并将大大推进该领域的贡献,
了解囊泡和蛋白质如何在这种病原体中运输。
项目成果
期刊论文数量(0)
专著数量(0)
科研奖励数量(0)
会议论文数量(0)
专利数量(0)
数据更新时间:{{ journalArticles.updateTime }}
{{
item.title }}
{{ item.translation_title }}
- DOI:
{{ item.doi }} - 发表时间:
{{ item.publish_year }} - 期刊:
- 影响因子:{{ item.factor }}
- 作者:
{{ item.authors }} - 通讯作者:
{{ item.author }}
数据更新时间:{{ journalArticles.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ monograph.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ sciAawards.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ conferencePapers.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ patent.updateTime }}
LESLY A TEMESVARI其他文献
LESLY A TEMESVARI的其他文献
{{
item.title }}
{{ item.translation_title }}
- DOI:
{{ item.doi }} - 发表时间:
{{ item.publish_year }} - 期刊:
- 影响因子:{{ item.factor }}
- 作者:
{{ item.authors }} - 通讯作者:
{{ item.author }}
{{ truncateString('LESLY A TEMESVARI', 18)}}的其他基金
COBRE:Eukaryotic Pathogens Innovation Center (EPIC)
COBRE:真核病原体创新中心(EPIC)
- 批准号:
9261570 - 财政年份:2016
- 资助金额:
$ 17.5万 - 项目类别:
COBRE:Eukaryotic Pathogens Innovation Center (EPIC)
COBRE:真核病原体创新中心(EPIC)
- 批准号:
9900800 - 财政年份:2016
- 资助金额:
$ 17.5万 - 项目类别:
Stress Induced Control of Protein Translation in Entamoeba Histolytica
应激诱导的溶组织内阿米巴蛋白质翻译控制
- 批准号:
8664552 - 财政年份:2014
- 资助金额:
$ 17.5万 - 项目类别:
A forward genetics screen for genes regulating phagocytosis and signaling in Enta
Enta 中调节吞噬作用和信号传导基因的正向遗传学筛选
- 批准号:
7573223 - 财政年份:2009
- 资助金额:
$ 17.5万 - 项目类别:
A forward genetics screen for genes regulating phagocytosis and signaling in Enta
Enta 中调节吞噬作用和信号传导基因的正向遗传学筛选
- 批准号:
7876802 - 财政年份:2009
- 资助金额:
$ 17.5万 - 项目类别:
Role of lipid rafts and phosphoinositides in E. histolytica virulence
脂筏和磷酸肌醇在溶组织内阿米巴毒力中的作用
- 批准号:
7652365 - 财政年份:2001
- 资助金额:
$ 17.5万 - 项目类别:
相似海外基金
Intercellular communication and host function modification via extracellular vesicles in Entamoeba histolytica
溶组织内阿米巴通过细胞外囊泡进行细胞间通讯和宿主功能修饰
- 批准号:
23K06514 - 财政年份:2023
- 资助金额:
$ 17.5万 - 项目类别:
Grant-in-Aid for Scientific Research (C)
Identification and characterization of early encystation genes in the human parasite Entamoeba histolytica
人类寄生虫溶组织内阿米巴早期成囊基因的鉴定和表征
- 批准号:
10647086 - 财政年份:2023
- 资助金额:
$ 17.5万 - 项目类别:
Modeling Entamoeba histolytica host-parasite interactions
溶组织内阿米巴宿主-寄生虫相互作用建模
- 批准号:
RGPIN-2019-04136 - 财政年份:2022
- 资助金额:
$ 17.5万 - 项目类别:
Discovery Grants Program - Individual
Molecular basis for the regulation of Entamoeba histolytica Igl lectin
溶组织内阿米巴 Igl 凝集素调节的分子基础
- 批准号:
22K05331 - 财政年份:2022
- 资助金额:
$ 17.5万 - 项目类别:
Grant-in-Aid for Scientific Research (C)
Modeling Entamoeba histolytica host-parasite interactions
溶组织内阿米巴宿主-寄生虫相互作用建模
- 批准号:
RGPIN-2019-04136 - 财政年份:2021
- 资助金额:
$ 17.5万 - 项目类别:
Discovery Grants Program - Individual
Elucidation of the virulence factor transport mechanism of Entamoeba histolytica based on the retromer complex
基于retromer复合物阐明溶组织内阿米巴毒力因子转运机制
- 批准号:
21K15426 - 财政年份:2021
- 资助金额:
$ 17.5万 - 项目类别:
Grant-in-Aid for Early-Career Scientists
Unraveling the role of membrane contact sites in Entamoeba histolytica
揭示溶组织内阿米巴膜接触位点的作用
- 批准号:
20K16233 - 财政年份:2020
- 资助金额:
$ 17.5万 - 项目类别:
Grant-in-Aid for Early-Career Scientists
Modeling Entamoeba histolytica host-parasite interactions
溶组织内阿米巴宿主-寄生虫相互作用建模
- 批准号:
RGPIN-2019-04136 - 财政年份:2020
- 资助金额:
$ 17.5万 - 项目类别:
Discovery Grants Program - Individual
Defining how Entamoeba histolytica nibbles vs. devours human cells
定义溶组织内阿米巴如何蚕食与吞噬人类细胞
- 批准号:
10043675 - 财政年份:2020
- 资助金额:
$ 17.5万 - 项目类别: