DIFFERENTIAL EXPRESSION OF ODORANT BINDING PROTEINS

天蛾的三种同源气味结合蛋白 sexta在嗅觉神经元上皮中唯一表达; 相应的OBP在神经元的不同结构域中表达， 上皮细胞和OBP表达是由昆虫中的下降诱导的， 类固醇激素20-羟基蜕皮激素。差异表达的证据 来自生化和组织学研究。类固醇的证据 调控来自组织培养研究。三个人的DNA互补 OBP已被克隆和测序，并在手中。实验 在本申请中提出的研究监管机制， 解释OBP的差异表达和类固醇调节 基因. 嗅觉器官的发育以渐进的方式发生， 至少有三个层次的空间组织：嗅觉 器官包含神经元和非神经元上皮的结构域; 神经元上皮被细分为包含不同子集的域 相同表型的神经元均匀分布 但被认为聚集在一个表型上， 大脑中的特定部位。这种组织在大鼠和 昆虫;该组织的机制可能是高度 在不同的动物群体中保存。M. sexta OBP反映了这个组织。分枝Sexta OBP代表简单的， 可利用的工具，以确定和控制空间和 嗅觉发育过程中的时间调控基因表达 嗅觉器官和嗅觉神经上皮。 提出了四个具体目标：（1）细胞的组织学分析 和亚细胞分布。Sexta OBP;（2）分离， 对来自M. sexta 现有的基因组文库;（3）鉴定可能的DNA OBP基因中的调控序列， 差异表达;（4）分子水平鉴定 类固醇激素对OBP表达调控及可能的DNA鉴定 对类固醇敏感的调节序列。

The three homologous Odorant Binding Proteins (OBPs) of the moth Manduca sexta are uniquely expressed in the olfactory neuronal epithelium; the respective OBPs are expressed in different domains of the neuronal epithelium and OBP expression is induced by a decline in the insect steroid hormone 20-hydroxy ecdysone. Evidence for differential expression is from biochemical and histological studies. Evidence for steroid regulation is from tissue culture studies. Complementary DNAs of all three OBPs have been cloned and sequenced and are in hand. The experiments proposed in this application examine the regulatory mechanisms that account for differential expression and steroid regulation of the OBP genes. Development of the olfactory organ occurs in a progressive manner to form a tissue with at least three levels of spatial organization: the olfactory organ contains domains of neuronal and non-neuronal epithelium; the neuronal epithelium is subdivided into domains containing distinct subsets of olfactory neurons; neurons of the same phenotype are evenly distributed within their domain but are thought to converge onto a phenotypically defined site in the brain. This organization is observed in both rat and insect; the mechanisms underlying this organization may be highly conserved among different animal groups. The expression of the M. sexta OBPs reflects this organization. The M. sexta OBPs represent simple and accessible tools for identifying and mechanisms controlling spatially and temporally regulated gene expression during development of the olfactory organ and the olfactory neuronal epithelium. Four specific aims are proposed: (l) histological analysis of the cellular and subcellular distributions of the three M. sexta OBPs; (2) isolation, sequencing and characterization of the three OBP genes from a M. sexta genomic library that is in hand; (3) identification of possible DNA regulatory sequences in the OBP genes that are responsible for differential expression; (4) identification of the molecular level of steroid regulation of OBP expression and identification of possible DNA regulatory sequences sensitive to steroid.