Carson J H, Worboys K, Ainger K, Barbarese E
Department of Biochemistry, University of Connecticut Health Center, Farmington 06030, USA.
Cell Motil Cytoskeleton. 1997;38(4):318-28. doi: 10.1002/(SICI)1097-0169(1997)38:4<318::AID-CM2>3.0.CO;2-#.
Myelin basic protein (MBP) mRNA is localized to the myelin membranes of oligodendrocytes. When exogenous MBP mRNA is microinjected into oligodendrocytes in culture, it is transported along the processes and localized to the myelin compartment in a multistep intracellular RNA trafficking pathway. In the work described here, oligodendrocytes were treated with agents that affect the cytoskeleton including: nocodazole, to disrupt microtubules; taxol, to stabilize microtubules; cytochalasin, to disrupt microfilaments; and kinesin anti-sense oligonucleotide, to suppress kinesin expression. Digoxigenin-labeled MBP mRNA was microinjected into the treated cells and the extent of translocation of the microinjected RNA was determined by confocal microscopy. Nocodazole, taxol, and kinesin anti-sense oligonucleotide inhibited translocation of microinjected MBP mRNA, while cytochalasin B and kinesin sense oligonucleotide did not. These results indicate that translocation of MBP mRNA in oligodendrocytes requires intact microtubules and kinesin but does not require intact microfilaments. The results are discussed in relation to the current multistep model for intracellular RNA trafficking in oligodendrocytes.
髓鞘碱性蛋白（MBP）mRNA定位于少突胶质细胞的髓鞘膜上。当将外源性MBP mRNA显微注射到培养的少突胶质细胞中时，它会沿着突起运输，并通过多步骤细胞内RNA运输途径定位于髓鞘区室。在本文所述的研究中，用影响细胞骨架的试剂处理少突胶质细胞，这些试剂包括：诺考达唑，用于破坏微管；紫杉醇，用于稳定微管；细胞松弛素，用于破坏微丝；以及驱动蛋白反义寡核苷酸，用于抑制驱动蛋白表达。将地高辛标记的MBP mRNA显微注射到处理过的细胞中，并通过共聚焦显微镜确定显微注射的RNA的转位程度。诺考达唑、紫杉醇和驱动蛋白反义寡核苷酸抑制了显微注射的MBP mRNA的转位，而细胞松弛素B和驱动蛋白正义寡核苷酸则没有。这些结果表明，少突胶质细胞中MBP mRNA的转位需要完整的微管和驱动蛋白，但不需要完整的微丝。结合当前关于少突胶质细胞内RNA运输的多步骤模型对这些结果进行了讨论。
