Stem cell and regeneration regulatory genes in planarians

涡虫的干细胞和再生调控基因

• 批准号: 9068155
• 负责人: PETER REDDIEN
• 金额: $ 37.05万
• 依托单位: WHITEHEAD INSTITUTE FOR BIOMEDICAL RES
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-20 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9068155
• 关键词: Address; Animals; Area; Biological Assay; Biological Models; Biology; Body part; Cell Lineage; Cells; Cellular Assay; Coupled; Cues; Decapitation; Eye; Eye Injuries; Family; Flow Cytometry; Fresh Water; Gene Expression; Genes; Genetic; Genetic study; Genome; Germ Layers; Goals; Grant; Growth; Head; Health; Heart; Heterogeneity; Human; Human Biology; Human Genome; In Situ Hybridization; Injury; Kidney; Maintenance; Malignant Neoplasms; Messenger RNA; Methodology; Modeling; Molecular; Molecular Genetics; Natural regeneration; Organ; Organism; Planarians; Platyhelminths; Population; Procedures; Public Health; RNA Interference; Regenerative Medicine; Regenerative response; Regulation; Regulator Genes; Role; Staging; Stem cells; System; Tail; Tissues; Transplantation; adult stem cell; aged; base; cancer type; cell type; eye regeneration; gene discovery; genetic manipulation; human disease; in vivo; injured; interest; mature animal; migration; nano-string; pluripotency; progenitor; programs; regenerative; response; self-renewal; signal processing; stem cell biology; tissue repair; tool; transcription factor; transcriptome sequencing; wound

DESCRIPTION (provided by applicant): Planarian flatworms are famous for their ability to rapidly regenerate new heads or even entire organisms from a tiny fragment of the animal. Planarian regeneration involves a population of proliferative cells (neoblasts) that include pluripotent adult stem cells (cNeoblasts) that can produce every cell of the adult animal. Despite centuries of fascination with regeneration, mechanistic explanations await elucidation. The broad, long-term objectives of this proposal are to use planarians as a model system to identify and understand the molecular mechanisms that regulate stem cells to promote regeneration. The specific aims are: 1) to determine the functions of neoblast regulatory genes, 2) to identify the cellular basis for regeneration, and 3) to identify wound-induced mechanisms that activate neoblast regenerative responses. Stem cells and regenerative biology are the subjects of recent and intense interest for regenerative medicine. In addition, the misregulation of stem cells may be central to many types of cancer. A newly developed arsenal of tools for molecular genetic study of planarians now exists. For example, systematic gene perturbation with RNA interference (RNAi) is now possible and the planarian genome has been sequenced. Greater than half of planarian genes have counterparts in the human genome; therefore, planarian studies should identify conserved stem cell regulatory genes. Aim #1 will determine the role of the transcription factor SoxP-1 in regulating gene expression in the neoblasts, utilizing RNAi, flow cytometry, and quantitative mRNA sequencing (RNA-seq). cNeoblasts can produce colonies of descendant cells including neoblasts and differentiating cells spanning germ layers. Aim #1 will utilize features of cNeoblast colonies to characterize roles for genes with enriched expression in the neoblast population. Aim #2 will utilize RNA seq and in situ hybridizations to identify the molecular features of the cNeoblast that distinguish it from lineage-committed descendant cells. Aim #2 will also utilize cNeoblast isolation and transplantation to develop neoblast genetic manipulation tools. Aim #3 will determine how organ precursors respond to injuries that remove target tissues. Specifically, eyes will be injured partially or completely to investigate whether eye precursors are induced by small eye injuries and in appropriate numbers tailored to the injury type. Finally, the roles of genes induced to be expressed in neoblasts following injury, including two genes encoding conserved Runx-family transcription factors, will be determined using RNAi and cellular assays for neoblast response to wounds. Successful completion of proposed aims will greatly advance our understanding of the mechanistic basis for regeneration and advance planarians as a model system for the study of genes conserved in humans in stem cell and regenerative biology, areas of great importance in human health.

描述(申请人提供)：扁虫是著名的能力，他们能够迅速再生新的头，甚至整个生物体从动物的一个很小的片段。脊椎动物的再生涉及一组增殖细胞(新生成体细胞)，其中包括能够产生成年动物每一个细胞的多能成体干细胞(CNeoblast)。尽管几个世纪以来人们一直痴迷于再生，但机械论的解释仍有待阐明。这项提议的广泛、长期的目标是使用有轨生物作为一个模型系统来识别和理解调节干细胞以促进再生的分子机制。其具体目的是：1)确定新生细胞调控基因的功能，2)确定再生的细胞基础，3)确定创伤诱导的激活新生细胞再生反应的机制。干细胞和再生生物学是近年来再生医学研究的热点。此外，干细胞的失调可能是许多类型癌症的核心。一种新开发的用于研究行星动物分子遗传学的工具库现已存在。例如，利用RNA干扰(RNAi)进行系统的基因干扰(RNAi)现在是可能的，并且已经对脊椎动物的基因组进行了测序。超过一半的脊椎动物基因在人类基因组中有对应的基因；因此，脊椎动物研究应该识别保守的干细胞调控基因。目的1利用RNAi、流式细胞术和定量mRNA测序(RNA-seq)技术，研究转录因子SoxP-1在新生细胞基因表达调控中的作用。新生细胞可以产生子代细胞集落，包括新生母细胞和跨越生殖层的分化细胞。目的#1将利用新生细胞集落的特征来表征在新生细胞群体中丰富表达的基因的作用。目的#2将利用RNA序列和原位杂交来鉴定cNeoblast的分子特征，以将其与血统承诺的后代细胞区分开来。目的#2还将利用新生细胞分离和移植来开发新生细胞遗传操作工具。目标3将确定器官前体如何对移除靶组织的损伤做出反应。具体地说，眼睛将被部分或全部损伤，以调查眼睛前体是否由轻微的眼睛损伤引起，并根据损伤类型定制适当的数量。最后，损伤后诱导表达的基因，包括两个编码保守的RUNX家族转录因子的基因，将通过RNAi和细胞分析来确定新生细胞对创伤的反应。所提出的目标的成功完成将极大地促进我们对再生的机制基础的理解，并推动平面动物作为研究干细胞和再生生物学中人类保守基因的模式系统，这两个领域对人类健康非常重要。