de Brabander M, Nuydens R, Ishihara A, Holifield B, Jacobson K, Geerts H
Department of Cellular Biology and Pathology, Janssen Research Foundation, Beerse, Belgium.
J Cell Biol. 1991 Jan;112(1):111-24. doi: 10.1083/jcb.112.1.111.
A recently introduced extension of video-enhanced light microscopy, called Nanovid microscopy, documents the dynamic reorganization of individual cell surface components on living cells. 40-microns colloidal gold probes coupled to different types of poly-L-lysine label negative cell surface components of PTK2 cells. Evidence is provided that they bind to negative sialic acid residues of glycoproteins, probably through nonspecific electrostatic interactions. The gold probes, coupled to short poly-L-lysine molecules (4 kD) displayed Brownian motion, with a diffusion coefficient in the range 0.1-0.2 micron2/s. A diffusion coefficient in the 0.1 micron2/s range was also observed with 40-nm gold probes coupled to an antibody against the lipid-linked Thy-1 antigen on 3T3 fibroblasts. Diffusion of these probes is largely confined to apparent microdomains of 1-2 microns in size. On the other hand, the gold probes, coupled to long poly-L-lysine molecules (240 kD) molecules and bound to the leading lamella, were driven rearward, toward the boundary between lamelloplasm and perinuclear cytoplasm at a velocity of 0.5-1 micron/min by a directed ATP-dependent mechanism. This uniform motion was inhibited by cytochalasin, suggesting actin microfilament involvement. A similar behavior on MO cells was observed when the antibody-labeled gold served as a marker for the PGP-1 (GP-80) antigen. These results show that Nanovid microscopy, offering the possibility to observe the motion of individual specific cell surface components, provides a new and powerful tool to study the dynamic reorganization of the cell membrane during locomotion and in other biological contexts as well.
一种最近引入的视频增强光学显微镜扩展技术，称为纳米视频显微镜，记录了活细胞上单个细胞表面成分的动态重组。与不同类型聚-L-赖氨酸偶联的40微米胶体金探针标记PTK2细胞的阴性细胞表面成分。有证据表明它们可能通过非特异性静电相互作用与糖蛋白的阴性唾液酸残基结合。与短聚-L-赖氨酸分子（4 kD）偶联的金探针呈现布朗运动，扩散系数在0.1-0.2微米²/秒范围内。在3T3成纤维细胞上，与抗脂质连接的Thy-1抗原抗体偶联的40纳米金探针也观察到了0.1微米²/秒范围内的扩散系数。这些探针的扩散主要局限于大小为1-2微米的明显微区。另一方面，与长聚-L-赖氨酸分子（240 kD）偶联并结合到前缘片层的金探针，通过一种依赖ATP的定向机制，以0.5-1微米/分钟的速度向后朝着片层质和核周细胞质之间的边界移动。这种均匀运动被细胞松弛素抑制，表明肌动蛋白微丝参与其中。当抗体标记的金作为PGP-1（GP-80）抗原的标记物时，在MO细胞上观察到了类似的行为。这些结果表明，纳米视频显微镜能够观察单个特定细胞表面成分的运动，为研究细胞膜在运动过程以及其他生物学背景下的动态重组提供了一种新的强大工具。
