IN SITU LOCALIZATION OF INFORMATIONAL EMBRYO RNAS

我们正在研究信息RNA的空间分布模式 在紫球海胆的发育过程中。去做 这是我们已经开发的，并正在继续改进的技术，用于 代表单个RNA序列的DNA探针与 固定和分割的鸡蛋和煎饼。我们将研究在多大程度上 单个信使RNA在不同类型的细胞中划分为 不同的发育阶段，以及每个细胞谱系的时间 获取其独特的一组mRNA。这些研究将给出一个索引 发育中不同细胞中基因表达的真正差异性 胚胎，以及这些RMA的每个细胞的实际浓度。我们会 多基因成员差异表达的空间模式研究 家人。对于组蛋白基因，我们会问是否所有的组蛋白基因 胚胎使基因表达从早期组蛋白切换到晚期组蛋白 变异的mRNAs以一种协调的方式，或者是开关的时间 对于不同的细胞谱系是不同的。对于多个肌动蛋白基因，我们 会问哪些基因在不同阶段的哪些细胞中表达 发展。我们将检查RNA转录本的分布 重复DNA序列，包括存储的母体细胞质重复序列 转录本，以及在后期细胞核中表达的那些。我们会 确定单个重复序列家族的转录本 仅限于卵子细胞质的特定区域和特定细胞 刺绣的世系与拟议的法规保持一致 这些序列的函数。

We are investigating spatial patterns of distribution of informational RNAs during development of the sea urchin Strongylocentrotus purpuratus. To do this we have developed, and are continuing to improve, techniques for in sity hybridization of DNA probes representing individual RNA sequences to fixed and sectioned eggs and embroys. We will examine the extent to which individual messenger RNAs are partitioned among different cell types at different stages of development, and the time at which each cell lineage acquires its unique set of mRNAs. These studies will give an index of the true diversity of gene expression in different cells of the developing embryo, as well as actual concentrations per cell of these RMAs. We will study spatial patterns of differential expression of members of multigene families. For the histone genes, we will ask whether all lcells of the embryo make the switch in gene expression form early to late histone variant mRNAs in a coordinate manner, or whether the timing of the switch is different for individual cell lineages. For multiple actin genes, we will ask which genes are expressed in which cells at various stages of development. We will examine the distribution of RNA transcripts of repetitive DNA sequences, including both stored maternal cytoplasmic repeat transcripts, and those expressed in nuclei of later stages. We will determine whether transcripts of individual repetitive sequence families are restricted to defined regions of the egg cytoplasm and to specific cell lineages of the embroy in a manner consistent with proposed regulatory functions for these sequences.