MOLECULAR CHARACTERIZATION OF THE RHODOPSIN GENE

视紫红质基因结构特征与 调控其表达的分子机制， 和感光细胞的存活是重要的神经生物学 这些问题相对来说知之甚少。 总体目标 这5年的研究计划是表征分子结构 和小鼠视紫红质基因的功能。 这包括对 其表达受遗传和环境（光与 暗）因素及其控制机制的研究 在正常小鼠和遗传性小鼠发育过程中的表达 视觉缺陷。 视蛋白和48 k（S-抗原， Arrestin）以非协调的方式受到光和/或 光/暗周期，动物暴露于其中。 此外该 视杆细胞中许多感光细胞特异性蛋白的定位 内段和外段是瞬态的并且依赖于光。 的 mRNA浓度变化与 光感受器特异性蛋白质与发育，基因型， 将通过西方和北方分析以及 免疫细胞化学 小鼠视蛋白基因已经被克隆， 测序，并证明了推定的调控序列。 顺式 核苷酸序列和反式作用因子，它们参与 光介导的反应将使用DNA阻滞试验来鉴定 和转染研究。 基因的确切染色体位点 小鼠视紫红质和48 k将使用Southern分析来确定， 中国仓鼠-小鼠体细胞基因组DNA限制性内切酶分析 细胞杂交和来自小鼠的重组近交系。 结构 这些基因的表达将在突变小鼠中进行检测 其映射在其位点处或附近。 的核苷酸序列 将确定所鉴定的视紫红质基因的等位基因形式， 视紫红质基因的定性和定量活性 单独测定这些基因，以及与突变（rd）组合测定 和RDS），其引起遗传性视网膜变性和转录 以及对视蛋白基因表达的转录后效应， 在感光细胞死亡之前。 分子结构 小鼠视紫红质基因的五个转录本的功能将 在正常和突变小鼠中测定。 由此产生的数据 项目可以增加我们对正常过程的理解， 人类的光传导和/或遗传性 视网膜变性

The relationship of the structural features of the rhodopsin gene and the molecular mechanisms regulating its expression, to phototransduction and to the survival of photoreceptor cells are important neurobiological problems about which relatively little is known. The overall objective of this 5 year research plan is to characterize the molecular structure and function of the mouse rhodopsin gene. This includes studies on the regulation of its expression by genetic and environmental (light vs. dark) factors and the investigation of the mechanisms controlling its expression during development of normal mice and of mice with inherited visual defects. The amounts of mRNA for opsin and 48k (S-antigen, Arrestin) are regulated in a non-coordinate manner by light and/or the light/dark cycle to which the animal is exposed. In addition, the localization of a number of photoreceptor specific proteins in the rod inner and outer segments is transient and dependent on light. The relationship between the changes in concentration of mRNAs and photoreceptor specific proteins with respect to development, genotype, and light will be determined by Western and Northern analysis and by immunocytochemistry. The mouse opsin gene has been cloned and sequenced, and putative regulatory sequence demonstrated. Cis-acting nucleotide sequences and trans-acting factors which participate in the light mediated responses will be identified using DNA retardation assays and transfection studies. The exact chromosomal loci for the genes for mouse rhodopsin and 48k will be determined using Southern analysis of restriction digests of genomic DNA from Chinese hamster-mouse somatic cell hybrids and from recombinant inbred lines of mice. The structure and expression of these genes will be examined in mice with mutations which map at or near to their loci. The nucleotide sequences of identified allelic forms of the rhodopsin gene will be determined and the qualitative and quantitative activity of the rhodopsin gene determined for these genes alone, and in combination with mutations (rd and rds) which cause inherited retinal degeneration and transcriptional and post transcriptional effects on the expression of the opsin gene, prior to the death of the photoreceptor cells. The molecular structure and function of the five transcripts from the mouse rhodopsin gene will be determined in normal and mutant mice. The data generated by this project may increase our understanding of the normal process of phototransduction in man and/or the molecular pathology of inherited retinal degeneration.