Gene expression of muscle proteins and molecular mechanisms of contractile structure formation

肌肉蛋白的基因表达和收缩结构形成的分子机制

基本信息

批准号：
09670002
负责人：
SHIMADA Yutaka
金额：
$ 2.3万
依托单位：
Chiba University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

1. Developmental relationship of myosin binding proteins to myosin during myofibrillogenesis :Immunofluorescence microscopy of embryonic skeletal muscle revealed that myomesin, connectin and C-protein play an important role for assembly and regular alignment of myosin molecules. It has also been suggested that a mechanism works to remore transiently expressed embryonic isoforms (non-muscle actin and cardiac C-protein) from functional structures after they play some unknown role(s) for structure formation.2. Dynamics of actin during myofibrillogenesis :Rhodamine (rh)-labeled actin was microinjected into cultured skeletal muscle cells and stained with anti-nebulin and anti-connectin. It was found that nebulin plays an important role for incorporaton of actin into and exchange of actin in nascent myofibrils, but connectin does not have such a role. This was confirmed by injection of anti-nebulin and anti-connectin to rh-actin injection.3. Dynamics of actin and α-actinin in myofibrils and stress fibers:Co-injection of fluorescently labeled actin and α-actinin into cultured cardiomyocytes revealed difference in exchangeability between both proteins in developing myofibrils. This difference seems to be related to the formation of I-Z-I structure of myofibrils. Exchangeability of bothproteins in stress fibers of fibroblasts was high, and thus myofibrils and stress fibers are different structures although they are similar in appearance and composition.

1.肌原纤维形成过程中肌球蛋白结合蛋白与肌球蛋白的发育关系：胚胎骨骼肌的免疫荧光显微镜显示肌球蛋白、连接蛋白和C蛋白在肌球蛋白分子的组装和规则排列中发挥着重要作用，也有人提出了一种机制。在发挥一些未知的结构作用后，从功能结构中去除瞬时表达的胚胎亚型（非肌肉肌动蛋白和心脏 C 蛋白） 2.肌原纤维形成过程中肌动蛋白的动态：将罗丹明（rh）标记的肌动蛋白显微注射到培养的骨骼肌细胞中并用抗nebulin和抗connectin染色发现nebulin在肌原纤维形成和肌原纤维形成过程中发挥重要作用。新生肌原纤维中肌动蛋白的交换，但连接蛋白没有这样的作用，这一点通过注射抗nebulin和抗nebulin得到证实。抗连接蛋白注射rh-肌动蛋白。3.肌原纤维和应力纤维中肌动蛋白和α-肌动蛋白的动态：将荧光标记的肌动蛋白和α-肌动蛋白共注射到培养的心肌细胞中揭示了两种蛋白质在发育中的肌原纤维之间的交换性差异。差异似乎与成纤维细胞应力纤维中两种蛋白质的I-Z-I结构的形成有关。肌原纤维和应力纤维虽然在外观和组成上相似，但结构不同。