GENETICS OF IRON BINDING PROTEINS AND AN ONCOFETOPROTEIN

这是一个建议，以表征克隆的DNA指定人类基因 编码一个调节铁的铁结合蛋白家族 代谢，对造血细胞前体施加控制，并触发 引发免疫反应。 转铁蛋白、乳转铁蛋白和 卵转铁蛋白是同源铁结合蛋白， 基因复制的进化产物。 它们由两个 类似的结构域，每一个都结合铁。 转铁蛋白是主要的血清 脊椎动物的铁结合蛋白。 它将吸收的铁 肠到骨髓，网织红细胞需要它， 血红蛋白生物合成。 转铁蛋白是所有增殖 细胞 转铁蛋白的氨基酸序列与 乳转铁蛋白，牛奶中的铁结合蛋白。 在鸡中， 转铁蛋白与卵转铁蛋白相同，卵转铁蛋白是一种在体内合成的糖蛋白， 鸡输卵管 铁结合糖蛋白的第四个成员是 由于它是最早的肿瘤抗原之一， 测序 抗原p97是人类黑色素瘤细胞膜所特有的。 的 抗原p97在结构和功能上与转铁蛋白相关， 能够与铁结合。 根据以下氨基酸序列构建的寡核苷酸探针： 用转铁蛋白、乳转铁蛋白和p97抗原筛选cDNA 图书馆. 将克隆对基因特异的cDNA插入物， 测序 染色体基因的序列分析应该能揭示 重复基因的产生机制 祖先基因 这些基因的染色体位置将是 通过原位杂交、印迹杂交和同线性研究 体细胞杂种的分析。 基因组p97的侧翼区域 基因最终将在黑色素瘤细胞中进行检测，并与 在非恶性细胞中的同源区域，以确定为什么p97是 在黑色素瘤细胞膜中特异性表达。 本研究将提供以下信息：（1）氨基酸序列， 人类蛋白质之间的同源性程度：转铁蛋白， 乳转铁蛋白和黑色素瘤抗原p97，（2）复制的基础 和铁结合糖蛋白基因的修饰，（3）染色体 转铁蛋白、乳转铁蛋白和黑色素瘤p97基因的定位 （4）黑色素瘤细胞中黑色素瘤p97抗原的表达。

This is a proposal to characterize the cloned DNAs specifying human genes which code for a family of iron binding proteins that modulate iron metabolism, exert controls on hemopoietic cell precursors and trigger the initiation of immunological reactions. Transferrin, lactotransferrin and ovotransferrin are homologous iron binding proteins which appear to be evolutionary products of gene duplication. They are comprised of two similar domains each of which binds iron. Transferrin is the major serum iron binding protein in vertebrates. It transports iron absorbed by the intestine to the bone marrow where it is required by reticulocytes for hemoglobin biosynthesis. Transferrin is required by all proliferating cells. Transferrin's amino acid sequence is homologous to lactotransferrin, an iron binding protein in milk. In chickens, transferrin is identical to ovotransferrin, a glycoprotein synthesized in chicken oviduct. The fourth member of the iron binding glycoproteins is of great biological interest since it is one of the first tumor antigens sequenced. Antigen p97 is unique to human melanoma cell membranes. The antigen p97 is structurally and functionally related to transferrin and is capable of binding iron. Oligonucleotide probes constructed according to the amino acid sequences of transferrin, lactotransferrin and antigen p97 will be used to screen cDNA libraries. The cDNA inserts specific for the genes will be cloned and sequenced. Sequence analysis of the chromosomal genes should reveal mechanisms involved in the generation of repeated genes by duplication of ancestral genes. The chromosomal locations of these genes will be investigated by in situ hybridization and by blot hybridization and synteny analysis of somatic cell hybrids. The flanking regions of the genomic p97 gene will ultimately be examined in melanoma cells and compared to homologous regions in non-malignant cells in order to determine why p97 is expressed specifically in melanoma cell membranes. This study will provide information about (1) the amino acid sequence and the degree of homology among the human proteins: transferrin, lactotransferrin and melanoma antigen p97, (2) the basis for duplication and modification of iron binding glycoprotein genes, (3) the chromosomal locations of the genes of transferrin, lactotransferrin and melanoma p97 antigen and (4) the expression of melanoma p97 antigen in melanoma cells.