DETERMINATION OF AN EARLY EMBRYONIC CELL LINEAGE

早期胚胎细胞谱系的测定

基本信息

批准号：
3321180
负责人：
RUDOLF A RAFF
金额：
$ 13.82万
依托单位：
TRUSTEES OF INDIANA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1986
资助国家：
美国
起止时间：
1986-09-01 至 1991-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/3321180
关键词：
cell cell interaction cell differentiation developmental genetics early embryonic stage embryo /fetus cell /tissue embryogenic cleavage gene expression immunoelectron microscopy immunofluorescence technique laboratory mouse laboratory rabbit mesenchyme molecular cloning monoclonal antibody nonmammalian vertebrate embryology nucleic acid sequence saltwater environment sea urchins

项目摘要

A critical feature of development is the early commitment of cells to very specific courses of gene action, functional differentiation, and morphogenesis. Both maternal and embryonic programs are involved in these events. The objective of the proposal is to study molecular mechanisms which govern the determination and differentiation of one such cell lineage: the primary mesenchyme cells which arise from the four micromeres of the 16-cell sea urchin embryo. Shortly before gastrulation, primary mesenchyme cells migrate into the blastocoel and initiate a precise program which culminates in secretion of the larval skeleton. Micromeres become committed at the 4th cleavage, and if isolated and cultured in vitro differentiate into mesenchyme cells and produce a skeleton. In this proposal we challenge the general view that primary mesenchyme differentiation is a fully autonomous process, and argue that it instead consists of both autonomous and cell interaction-dependent phases. We have isolated mesenchyme-specific cDNA clones as well as a set of monoclonal antibodies to the major cell lineages of the embryo. These we will use for studying the molecular events of mesenchyme differentiation and the roles of particular gene products. There are three major specific aims. (1) We will use clones of gene sequences with mesenchyme-limited expression to examine gene regulation and the functions of these genes in the lineage. (2) We will use mesenchyme-specific probes to investigate autonomous and non-autonomous processes in cultured mesenchyme cells. (3) There are inductive restrictions as well as positive determinative controls in sea urchin embryos. In the absence of micromeres the neighboring macromeres partially change fate and give rise to primary mesenchyme cells. This determinative event occurs in culture in isolated macromeres, and thus will provide an in vitro model system to study the molecular and cellular events of mesenchyme determination.

发育的一个关键特征是细胞早期致力于非常基因作用、功能分化的具体过程，以及形态发生。母体和胚胎程序都参与这些事件。该提案的目的是研究分子机制它控制着一种这样的细胞的决定和分化谱系：由四个微团产生的初级间充质细胞 16 细胞海胆胚胎。原肠胚形成前不久，初级间充质细胞迁移到囊胚腔并启动精确的程序最终导致幼虫骨骼的分泌。微团变成在第四次卵裂时发生，如果在体外分离和培养分化为间充质细胞并产生骨骼。在本提案中，我们挑战了初级间充质的普遍观点分化是一个完全自主的过程，并认为它相反由自主阶段和细胞相互作用依赖阶段组成。我们有分离的间充质特异性 cDNA 克隆以及一组单克隆针对胚胎主要细胞谱系的抗体。这些我们将用于研究间充质分化的分子事件及其作用特定基因产物。有三个主要的具体目标。 (1) 我们将使用具有间充质限制表达的基因序列克隆来检查基因调控以及这些基因在谱系中的功能。 (2) 我们将使用间充质特异性探针来研究自主和培养的间充质细胞中的非自主过程。 (3) 有海上的归纳限制和积极的决定性控制海胆胚胎。在没有微团的情况下，相邻的大团部分改变命运并产生原代间充质细胞。这决定性事件发生在培养物中的孤立大分子中，因此将提供体外模型系统来研究分子和细胞事件间质测定。