MYOFIBRILLAR PROTEIN EXPRESSION

在本项目中，我们计划研究肌原纤维形成的机制和控制。 和线粒体在过渡过程中的组装和降解 心肌处于两种稳定状态之间。周转所需的蛋白质 我们将研究不同的比率。主要目标是：1.确定 合成速率(Rs)或分数速率周转(Kp)是否发生变化 在生长的不同阶段。考虑到数据的异构性 蛋白质周转率是生长过程中必然发生变化的速率之一 为了维持体内单个蛋白质的恒定比例 细胞器。2.肌球蛋白HC在导致改变的条件下的特征 ATPase活性。假定的同工酶将根据以下方面进行表征 氨基酸序列(有限片段)和免疫学特性。这个 分离的HC的RS和Kp将在从一个同工酶过渡的过程中被测量 到另一个图案。3.确定相对分数税率是否 结构蛋白周转率和可溶性蛋白周转率发生变化 在加速降解过程中。蛋白质将根据以下方面进行评估 分子量、等电点和碳水化合物含量。4.政府部门的角色 钙激活中性蛋白酶(CAAP)在肌原纤维转化中的作用 重新检查。CAAP的细胞起源将由以下因素确定 免疫荧光。肌球蛋白HC和α-肌动蛋白的周转率将被测定 在培养的心肌细胞中，钙离子内流被离子载体增强。这个 肌丝的双六角晶格的稳定性将在之后进行检查 去甲型肌动蛋白。5.研究溶酶体蛋白水解酶在体内的作用。 肌原纤维的降解。将尝试检测肌球蛋白或其 制备的溶酶体组分中的高相对分子质量降解产物 来自肌肉。

In this project we propose to study the mechanism and control of myofibrillar and mitochondrial assembly and degradation during the transition of the myocardium between two steady states. The proteins which turnover with heterogeneous rates will be studied. The main objectives are: 1. To determine whether the rate of synthesis (Rs) or the fractional rate turnover (kp) change during various phases of growth. Considering the heterogeneous nature of the turnover of proteins one of the rates necessarily must be changing during growth in order to maintain a constant ratio of individual proteins within the organelle. 2. To characterize myosin HC under conditions leading to altered ATPase activity. The putative isoenzymes will be characterized with respect to amino acid sequence (limited fragmentation) and immunological properties. The Rs and kp of separated HC will be measured during transition from one isoenzyme pattern to another one. 3. To determine whether the relative fractional rates of turnover of structural proteins and those of the soluble proteins are changed during accelerated degradation. Proteins will be evaluated with respect to molecular weight, isoelectric point, and carbohydrate content. 4. The role of calcium-activated neutral protease (CaAp) in the turnover of myofibrils will be reexamined. The cellular origin of CaAp will be determined by immunofluorescence. Turnover of myosin HC and alpha-actinin will be determined in cultured heart cells after calcium influx is enhanced by an ionophore. The stability of the double hexagonal lattice of myofilaments will be examined after alpha-actinin removal. 5. To study the involvement of lysosomal proteases in the degradation of myofibrils. Attempts will be made to detect myosin or its high molecular-weight degradation products in the lysosomal fraction prepared from muscle.