MOLECULAR BIOLOGY OF ALPHA 1,3 FUCOSYLTRANSFERASE

这项工作的总体目标是确定调节机制， 哺乳动物寡糖分子的表达。 基化 选择低聚糖作为实验模型，因为它们 岩藻糖键，和同源岩藻糖转移酶负责 它们的生物合成，以时间和空间的精确性表达， 在哺乳动物的分化过程中， 与恶性转化有关。 这些特性表明， 这些分子的重要功能;这是最近才发现的 研究表明，一组特定的 岩藻糖基化低聚糖，由髓系细胞表达， 这些白细胞与内皮白细胞粘附分子I的粘附 在炎症期间。 为了解决这些分子表达的调节，我们 分离的基因和cDNA编码三种不同的 α（1，3）岩藻糖基转移酶。 这些代表的工具， 研究转录、转录后和结构-功能 确定不同的类型和相对数量的考虑因素 由细胞和组织产生的α（1，3）岩藻糖基化糖缀合物。 本提案的具体目标是： 1. 分析一个新的人类DNA序列的结构和功能 其可以编码α（1.3）岩藻糖基转移酶。 2. 为了分离克隆的，髓系cDNAs参与了 细胞表面唾液酸刘易斯x和Vim-2决定簇的生物合成。 3. 为了定义每个α（1，3）FT的生物合成和结构，使用 生物化学、分子遗传学和形态学方法。 4. 探讨α（1，3）FT受体与细胞凋亡的关系 底物特异性和一级序列决定簇 α（1，3）FT通过嵌合突变体的产生和测试 α（1，3）FTs。 5. 目的：明确正常人α（1，3）FT基因的表达模式 组织中

The overall goals of this work are to determine mechanisms that regulate expression of mammalian oligosaccharide molecules. Fucosylated oligosaccharides were chosen as an experimental model because their fucose linkages, and the cognate fucosyltransferases responsible for their biosynthesis, are expressed with temporal and spatial precision during mammalian differentiation, and are frequently altered in association with malignant transformation. These properties suggested important functions for these molecules; this has been born out recently by studies demonstrating that one or more members of a specific set of fucosylated oligosaccharides, expressed by cells of the myeloid lineage, adhesion of these leukocytes to endothelial leukocyte adhesion molecule I during inflammation. To address the regulation of expression of such molecules, we have isolated genes and cDNAs that encode three distinct alpha(1,3)fucosyltransferases. These represent tools with which to examine transcriptional, post-transcriptional, and structure-function considerations that determine the types and relative amounts of distinct alpha(1,3)fucosylated glycoconjugates made by cells and tissues. The SPECIFIC AIMS of this proposal are: 1. To analyze the structure and function of a novel human DNA sequence that may encode an alpha(1.3)fucosyltransferase. 2. To isolate cloned, myeloid-lineage cDNAs that participate in the biosynthesis of cell surface sialyl Lewis x and VIM-2 determinants. 3. To define the biosynthesis and structure of each alpha(1,3)FT, using biochemical, molecular genetic, and morphologic approaches. 4. To investigate the relationship between alpha(1,3)FT acceptor substrate specificity and primary sequence determinants within alpha(1,3)FTs via the creation and testing of chimeric, mutant alpha(1,3)FTs. 5. To define expression patterns of alpha(1,3)FT genes in normal human tissues.