HOMEO BOX GENES IN NON-SEGMENTED ECHINODERMS

海胆同源框基因将通过分子克隆进行研究 以及基因组DNA和cDNA的DNA核苷酸测序。首字母 基因组DNA克隆的选择将基于它们与 果蝇同源盒探头。这些序列和氨基酸序列 它们的编码将与其他物种的序列进行比较以推断 进化关系；还将确定克隆的 基因是相互关联的。基因组DNA和cDNA序列将与 阐明转录单位的结构。该组织的活动 海胆卵母细胞、卵、胚胎和成体组织中的转录单位 将通过探测与克隆的RNA凝胶传输进行研究 序列。转录本将定位于胚胎的组织切片 通过原位杂交。蛋白质产品将整体本地化 使用抗体探针通过免疫荧光显微镜观察胚胎。自海 海胆明显是无节段的，对这些发育的分析 控制海胆的基因将提供一个信息对比 来自目前正在研究的其他生物的数据，可能会建立一个 更好地理解含有Homeo盒的更一般的功能 调控位置信息传递的基因或 细胞命运的决定与建立的有限功能 同色异构体。 人们无法准确预测这些实验的医学意义。 当我们了解了基因被调控的方式时，我们就可以希望 使用此信息可以纠正此过程中的任何障碍。作为 Poly(A)尾巴的发现也为分离mRNA提供了工具 希望同源盒的发现为分离基因提供了一种工具 它调节其他基因的表达。智能网的进一步发展 研究基因表达和检测的体内和体外系统 正常或突变的Homeo对这些系统的影响 含有盒子的基因蛋白产品有朝一日可能使其成为可能 纠正人类发育障碍。基因表达的调控 也是癌症生物学中的一个中心问题。

Sea urchin homeo box-containing genes will be studied by molecular cloning and DNA nucleotide sequencing of both genomic DNA and cDNA. The initial selection of the genomic DNA clones will be based on their homology to Drosophila homeo box probes. These sequences and the amino acid sequences they encode will be compared to sequences from other species to infer evolutionary relationships; it will also be determined whether the cloned genes are linked. The genomic DNA and cDNA sequences will be compared to elucidate the structure of the transcription units. The activity of the transcription units in sea urchin oocytes, eggs, embryos and adult tissues will be investigated by probing RNA gel transfers with the cloned sequences. The transcripts will be localized in tissue sections of embryos by in situ hybridization. The protein products will be localized in whole embryos by immunofluorescence microscopy using antibody probes. Since sea urchins are distinctly non-segmented, an analysis of these development controlling genes in sea urchins will provide an informative contrast to the data from the other organisms currently under study and may establish a better understanding of the more general functions of homeo box-containing genes in regulating the transduction of positional information or the determination of cell fate versus the limited function of establishing metamerism. One cannot predict exactly the medical significance of these experiments. When we understand the manner in which genes are regulated, we can hope to use this information to correct any disorders in the process. As the discovery of poly(A) tails has provided a tool for isolating mRNA, so too may the discovery of homeo boxes have provided a tool for isolating genes which regulate the expression of other genes. Further development of in vivo and in vitro systems for studying gene expression and an examination of the effects on these systems caused by normal or mutated homeo box-containing gene protein products may one day make it possible to correct human developmental disorders. The regulation of gene expression is also a central problem in cancer biology.