Grolig F, Williamson R E, Parke J, Miller C, Anderton B H
Plant Cell Biology Group, Research School of Biological Sciences, Australian National University, Canberra.
Eur J Cell Biol. 1988 Oct;47(1):22-31.
A monoclonal antibody to the heavy chain of myosin from mouse 3T3 cells was used to detect and localize related proteins in the green alga Chara. Proteins of 200,000 and 110,000 Mr reacted on immunoblots of proteins precipitated rapidly with trichloroacetic acid to minimize proteolysis. Immunofluorescence of whole cells localized these proteins to organelles of the streaming endoplasm, to a system of endoplasmic strands and to the subcortical actin bundles. Except that fewer endoplasmic strands and organelles were found and the strands were tangled, the localization pattern was similar in cells rapidly perfused to remove the bulk of the streaming endoplasm. Actin was confined almost entirely to the system of subcortical actin bundles in both whole and perfused cells. Myosin that was associated with the tangled endoplasmic strands but not that associated with the organelles or actin bundles was removed by concentrations of Ca2+ inhibiting ATP-dependent streaming in perfused cells. ATP extracted both organelles and endoplasmic strands but left a continuous pattern of myosin immunostaining along the actin bundles. The findings are discussed in relation to the possible existence of two forms of myosin and of separate mechanisms moving the bulk endoplasm and individual organelles.
一种针对小鼠3T3细胞肌球蛋白重链的单克隆抗体被用于检测和定位绿藻轮藻中的相关蛋白。在经三氯乙酸快速沉淀以尽量减少蛋白水解的蛋白质免疫印迹中，分子量为200,000和110,000的蛋白质发生了反应。全细胞免疫荧光将这些蛋白质定位到流动内质的细胞器、内质丝系统以及皮层下肌动蛋白束。除了发现的内质丝和细胞器较少且丝状物缠结外，在快速灌注以去除大部分流动内质的细胞中，定位模式相似。在全细胞和灌注细胞中，肌动蛋白几乎完全局限于皮层下肌动蛋白束系统。与缠结的内质丝相关而非与细胞器或肌动蛋白束相关的肌球蛋白，在灌注细胞中通过抑制ATP依赖性流动的Ca2+浓度被去除。ATP提取了细胞器和内质丝，但在肌动蛋白束上留下了连续的肌球蛋白免疫染色模式。结合肌球蛋白可能存在两种形式以及存在移动内质总体和单个细胞器的不同机制，对这些发现进行了讨论。
