Chemoattractant-stimulated polymorphonuclear leukocytes contain two populations of actin filaments that differ in their spatial distributions and relative stabilities.
Chemoattractant-stimulated polymorphonuclear leukocytes contain two populations of actin filaments that differ in their spatial distributions and relative stabilities.
复制标题
化学吸引剂刺激的多形核白细胞包含两个肌动蛋白丝的种群，它们的空间分布和相对稳定性不同。
DOI：
10.1083/jcb.110.4.1067
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发表时间：
1990-04
期刊：
影响因子：
--
通讯作者：
Zigmond SH
中科院分区：
文献类型：
--
作者：
Cassimeris L;McNeill H;Zigmond SH
化学引诱剂刺激多形核白细胞片状足中的肌动蛋白聚合。我们发现化学引诱剂的去除会导致位于板状伪足中的 F-肌动蛋白快速（37 摄氏度下 10 秒内）和选择性解聚。在化学引诱剂存在下添加 10 microM 细胞松弛素 B 也导致层状 F-肌动蛋白快速选择性解聚。 (a) 趋化剂浓度降低 10 倍后，趋化剂诱导的 F-肌动蛋白水平升高迅速恢复到未刺激细胞中存在的水平； (b) 添加 10 microM 细胞松弛素 B； (c) 冷却至 4 摄氏度。未刺激细胞的 F-肌动蛋白水平仅受到这些处理的轻微影响。基于细胞松弛素添加和化学引诱剂稀释的相似效果，两种处理很可能导致肌动蛋白从丝的尖端解聚。根据我们的结果，我们提出化学引诱剂刺激的多形核白细胞含有两种不同的肌动蛋白丝群体。片状伪足内的肌动蛋白丝非常不稳定，在化学引诱剂持续存在的情况下，这些丝会迅速翻转，在其正端（有倒刺的）持续聚合，并在其负端解聚。相比之下，受刺激和未受刺激细胞的皮质 F-肌动蛋白丝的稳定性不同。
Chemoattractants stimulate actin polymerization in lamellipodia of polymorphonuclear leukocytes. We find that removal of chemoattractant results in rapid (within 10 s at 37 degrees C) and selective depolymerization of the F-actin located in lamellipodia. Addition of 10 microM cytochalasin B, in the presence of chemoattractant, also resulted in rapid and selective depolymerization of lamellar F-actin. The elevated F-actin level induced by chemoattractant rapidly returns to the level present in unstimulated cells after (a) a 10-fold decrease in chemoattractant concentration; (b) the addition of 10 microM cytochalasin B; or (c) cooling to 4 degrees C. The F-actin levels of unstimulated cells are only slightly affected by these treatments. Based on the similar effects of cytochalasin addition and chemoattractant dilution, it is likely that both treatments result in actin depolymerization from the pointed ends of filaments. Based on our results we propose that chemoattractant-stimulated polymorphonuclear leukocytes contain two distinct populations of actin filaments. The actin filaments within the lamellipodia are highly labile and in the continued presence of chemoattractant these filaments are rapidly turning over, continually polymerizing at their plus (barbed) ends, and depolymerizing at their minus ends. In contrast, the cortical F-actin filaments of both stimulated and unstimulated cells are differentially stable.