FUNCTIONS OF ANKYRINS IN MICE

锚蛋白是大的，广泛分布的，三重蛋白质， 整合膜转运蛋白、粘附蛋白和受体 血影蛋白膜骨架。 已经克隆了三种锚蛋白， 迄今为止的特征：Ank 1（红细胞锚蛋白），Ank 2（脑锚蛋白）， 和Ank3（上皮锚蛋白）。 每个锚蛋白含有一个N-末端 一个将锚蛋白附着在膜蛋白上的“重复”结构域， 中央血影蛋白结合结构域，和C-末端，"调节"结构域， 其功能未被描述。 Ank3也存在于一个较小的 同种型（Ank 3 - 5kb），其缺乏重复结构域。 在巨噬细胞中Ank 3 - 5kb 仅与晚期溶酶体和后溶酶体相关 囊泡 目前的研究旨在测试锚蛋白功能的各个方面 在体内，特别是Ank1是否可以被其他锚蛋白取代 以及用Ank 1替换原生Ank 1的后果 在调节域中承载结构变化。 这些问题 将使用小鼠靶向基因置换技术进行研究 胚胎干细胞（ES细胞）。 诱导突变对 存活率、器官功能和病理学、红细胞寿命和 形态学、红细胞膜和膜骨架组成， 组织，膜稳定性，以及带的功能和移动性 三是要调查。 其他实验将针对 鉴定将Ank 3 - 5kb靶向细胞内囊泡的序列， 鉴定和克隆靶配体。

Ankyrins are large, widely distributed, tripartite proteins that link integral membrane transporters, adhesive proteins and receptors to the spectrin-based membrane skeleton. Three ankyrins have been cloned and characterized so far: Ank1 (erythrocyte ankyrin), Ank2 (brain ankyrin), and Ank3 (epithelial ankyrin). Each ankyrin contains an N-terminal "repeat" domain that attaches ankyrin to integral membrane proteins, a central spectrin-binding domain, and a C-terminal, "regulatory" domain, whose function is not characterized. Ank3 also exists in a smaller isoform (Ank3-5kb)that lacks the repeat domain. In macrophages Ank3-5kb is associated exclusively with late lysosomes and post lysosomal vesicles. The present studies aim to test aspects of ankyrin function in vivo, particularly whether Ank1 can be replaced by the other ankyrins and what the consequences are of replacing native Ank1 with an Ank1 bearing structural changes in the regulatory domain. These questions will be pursued using the technique of targeted gene replacement in mouse embryonal stem (ES) cells. The effects of the induced mutations on survival, organ function and pathology, red cell life span and morphology, red cell membrane and membrane skeletal composition and organization, membrane stability, and the function and mobility of band 3 will be investigated. Additional experiments will be directed at identifying sequences that target Ank3-5 kb to intracellular vesicles and identifying and cloning the target ligand(s).