Desmin-Membrane Interactions in Skeletal Muscle

;​R o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o。/ 0 1 2 3 4 5 6 7 8 F Microsoft Word 6.0 Document MSWordDoc。6;​在脊椎动物胚胎中，一块块的骨骼肌细胞通过一个特殊的连接点相互连接，这个连接点被称为体细胞间连接点。这种连接在结构和功能上类似于成年动物连接肌肉、肌腱和骨骼的连接。聚丝型中间丝是肌细胞的结构成分，集中在体间连接处。我们实验室的研究表明，聚丝在维持肌原纤维与肌细胞膜在体间连接处的附着方面起着关键作用。虽然很清楚地知道，地蛋白可以与肌肉细胞膜相互作用，但参与这种相互作用的分子是未知的。在之前的NSF资助工作中，我们使用爪蟾来研究desmin的组织。我们确定了蛋白的n端头部区域介导蛋白与肌细胞膜之间的相互作用。在这里提出的研究中，我们将尝试识别结合desmin的肌膜蛋白。我们将使用最近设计的高灵敏度酵母双杂交系统。在这些研究中，desmin的头部结构域将用于筛选富含肌肉成分的cDNA文库。在这个筛选中分离的cDNA将被表征，以确定它们是否实际上在早期胚胎的肌肉细胞中表达。将对它们编码的蛋白质进行研究，以确定其定位和功能。为了实现它们的机械功能，中间细丝通常必须与膜相互作用。然而，中间丝状膜相互作用的分子细节却知之甚少。通过鉴定介导聚丝与肌肉细胞膜相互作用的蛋白质，我们将能够在分子水平上定义对正常肌肉细胞组织和功能至关重要的相互作用。*** ;Oh + 0 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $ H + 1 $R:模板\ WWUSER \ \正常。DOT 9418715雪莉帕克雪莉帕克@ E @ @ E @ f#微软Word 6.0;;e 3 e j j j j j @ 1 " q T 7 @ j @ j j在脊椎动物胚胎中，骨骼肌细胞块通过一个特殊的连接点相互连接，这个连接点被称为体细胞间连接点。这种连接在结构和功能上类似于成年动物连接肌肉、肌腱和骨骼的连接。聚丝型中间丝是肌细胞的结构成分，集中在体间连接处。我们实验室的研究表明，纤丝在维持肌原纤维与肌细胞膜的附着方面起着关键作用

; R o o t E n t r y F @ C o m p O b j b W o r d D o c u m e n t O b j e c t P o o l . / 0 1 2 3 4 5 6 7 8 F Microsoft Word 6.0 Document MSWordDoc Word.Document.6 ; 9418715 Kymkowsky In vertebrate embryos, blocks of skeletal muscle cells are attached to one another through a specialized junction, known as the intersomite junction. This junction is structurally and functionally similar to the junction that connects muscle to tendon and bone in adult animals. Desmin-type intermediate filaments are structural components of muscle cells and are found concentrated at the intersomite junction. Studies from our lab indicate that desmin filaments play a critical role in maintaining the attachment of myofibrils to the muscle cell membrane at the intersomite junction. Although it is clear that desmin can interact with the muscle cell membrane, the molecules involved in this interaction are unknown. In the course of previous NSF funded work, we used the frog Xenopus to study the organization of desmin. We determined the N-terminal head region of desmin mediates the interaction between desmin and the muscle cell membrane. In the studies proposed here we will attempt to identify muscle membrane proteins that bind desmin. We will use the recently devised, and high ly sensitive, yeast two-hybrid system. In these studies, the head domain of desmin will be used to screen a cDNA library enriched in muscle components. cDNA isolated in this screen will be characterized to determine whether they are in fact expressed in the muscle cells of the early embryo. Proteins that they encode will be studies to determine their localization and function. %%% To carry out their mechanical functions intermediate filaments generally must interact with membranes. Yet, the molecular details of intermediate filament-membrane interactions are poorly understood. By identifying proteins that mediate the interaction of desmin filaments with muscle cell membranes, we will be able to define, at the molecular level, interactions critical to normal muscle cell organization and function. *** ; Oh +' 0 $ H l D h S u m m a r y I n f o r m a t i o n ( - R:\WWUSER\TEMPLATE\NORMAL.DOT 9418715 Shirley Parker Shirley Parker @ E @ @ E @ F # Microsoft Word 6.0 1 ; ; e 3 e j j j j j j j @ 1 " q T 7 @ j @ j j j j ~ j j j j : 9418715 Kymkowsky In vertebrate embryos, blocks of skeletal muscle cells are attached to one another through a specialized junction, known as the intersomite junction. This junction is structurally and functionally similar to the junction that connects muscle to tendon and bone in adult animals. Desmin-type intermediate filaments are structural components of muscle cells and are found concentrated at the intersomite junction. Studies from our lab indicate that desmin filaments play a critical role in maintaining the attachment of myofibrils to the muscle cell mem