Stem cell and regeneration regulatory genes in planarians

涡虫的干细胞和再生调控基因

• 批准号: 8438964
• 负责人: PETER REDDIEN
• 金额: $ 36.69万
• 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/8438964
• 关键词: Address; Animals; Area; Biological Assay; Biological Models; Biology; Body part; Cell Lineage; Cells; Cellular Assay; Commit; Coupled; Cues; Decapitation; Eye; Eye Injuries; Family; Flow Cytometry; Fresh Water; Gene Expression; Genes; Genetic; 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; RNA Sequences; Regenerative Medicine; Regulation; Regulator Genes; Role; Staging; Stem cells; System; Tail; Tissues; Transplantation; adult stem cell; aged; base; cancer type; cell type; computerized data processing; eye regeneration; gene discovery; genetic manipulation; human disease; in vivo; injured; interest; mature animal; migration; nano-string; pluripotency; progenitor; programs; public health relevance; regenerative; response; self-renewal; 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（由申请人提供）：Planarian扁形虫以其从动物的微小片段快速再生新头部甚至整个生物体的能力而闻名。Planarian再生涉及一群增殖细胞（neoblast），其中包括多能成体干细胞（cNeoblast），可以产生成年动物的每个细胞。尽管几个世纪以来对再生的迷恋，机械的解释仍有待阐明。这项提议的广泛的长期目标是使用真涡虫作为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。具体目标是：1）确定新成纤维细胞调节基因的功能，2）确定再生的细胞基础，3）确定激活新成纤维细胞再生反应的伤口诱导机制。干细胞和再生生物学是再生医学最近和强烈兴趣的主题。此外，干细胞的失调可能是许多类型癌症的核心。一个新开发的武器库的分子遗传学研究的涡虫现在存在。例如，RNA干扰（RNAi）的系统性基因干扰现在是可能的，并且Planarian基因组已经测序。超过一半的涡虫基因在人类基因组中有对应的基因，因此，涡虫研究应该确定保守的干细胞调控基因。目的#1将利用RNAi、流式细胞术和定量mRNA测序（RNA-seq）来确定转录因子SoxP-1在新成细胞中调节基因表达的作用。cNeoblasts可以产生后代细胞的集落，包括neoblasts和跨越胚层的分化细胞。目标#1将利用cNeoblast集落的特征来表征在neoblast群体中具有富集表达的基因的作用。目标#2将利用RNA测序和原位杂交来鉴定cNeoblast的分子特征，以将其与谱系定向后代细胞区分开。目标#2还将利用cNeoblast分离和移植来开发neoblast遗传操作工具。目标3将确定器官前体如何对去除靶组织的损伤作出反应。具体而言，眼睛将部分或完全受伤，以研究眼睛前体是否由小的眼睛损伤引起，并根据损伤类型调整适当的数量。最后，将使用RNAi和细胞测定法确定损伤后在新生细胞中诱导表达的基因的作用，包括编码保守的Runx家族转录因子的两个基因，用于新生细胞对伤口的反应。成功完成拟议的目标将大大推进我们的理解的机制基础再生和先进的涡虫作为一个模型系统的研究基因保守的人类干细胞和再生生物学，在人类健康领域非常重要。