BIOCHEMISTRY AND GENETICS OF FERRITIN IN DROSOPHILIA

昆虫铁蛋白的结构及其表达调控是近年来研究的热点。 有两个主要原因。 首先，昆虫可以 用于研究复杂过程的有用生物模型，如饮食 铁吸收不涉及脊椎动物。 二是 了解昆虫的铁代谢可以提出新的策略， 控制作为疾病传播媒介的吸血昆虫。 与 考虑到这些目标，我们建议研究铁代谢， 曼陀罗 果蝇及其复杂的遗传学 提供了一个非常强大的系统，用于突变分析， 结构-功能关系。 在此基础上，我们建议扩大 利用黑腹果蝇研究昆虫铁蛋白 我们建议：1）表征铁蛋白，并开发分子探针， 黑腹果蝇铁蛋白; 20个铁蛋白基因定位于多线体 染色体图谱，并确定铁蛋白的调节模式 在发育过程中和不同铁的条件下表达 3）获得铁蛋白突变体，并使用它们来研究铁蛋白的丰度。 D.铁蛋白结构与功能黑腹菌 为了实现这些目标，我们提出：纯化黑腹果蝇铁蛋白 幼虫和表征它;产生针对它的抗体，确定N- 铁蛋白亚基（s 0）末端序列及其cDNA克隆; 通过多线染色体原位杂交定位铁蛋白基因; 研究铁蛋白的发育和铁调节表达， Western和北方印迹;产生和分析铁蛋白无效突变体 并通过P元件介导的转化来拯救它们。

The structure of insect ferritins and the regulation of their expression is of particular interest for two main reasons. Firstly, insects can be useful biological models for studying complex processes, such as dietary iron absorption without involving vertebrate animals. Secondly, the understanding of insect iron metabolism could suggest new strategies for control of hematophagous insects that act as vectors of disease. With these goals in mind we have proposed to study the iron metabolism in Manduca sexta. Drosophila melanogaster with its sophisticated genetics provides an extremely powerful system for mutational analysis of the structure-function relationships. Based on this we propose to expand the study of insect ferritins using D.melanogaster. We propose to: 1) characterize ferritin and develop molecular probes for ferritin from D.melanogaster; 20 localize ferritin genes on polytene chromosome maps and determine the pattern of regulation of ferritin expression during development and under conditions of different iron abundance' and 3) obtain ferritin mutants and use them to study the structure and function of ferritin in D. melanogaster. To achieve these goals we propose to: purify ferritin from D.melanogaster larvae and characterize it; produce antibodies against it, determine N- terminal sequence of ferritin subunits(s0 and clone cDNAs for them; localize ferritin gene(s) by in situ hybridization on polytene chromosomes; study the developmental and iron-regulated expression of ferritin by western and northern blotting; produce and analyze ferritin null mutants and rescue them by P-element mediated transformation.