Shea T B
Ralph Lowell Laboratories, McLean Hospital, Belmont, MA 02178.
Brain Res. 1990 Jun 25;521(1-2):338-42. doi: 10.1016/0006-8993(90)91563-v.
The localization of vimentin (Vm) within the Triton-insoluble cytoskeleton was characterized during differentiation of mouse NB2a/dl neuroblastoma cells. Vm staining increased within neurites during the first day of differentiation, and then rapidly declined in both perikarya and neurites. By contrast, immunoreactivity against extensively phosphorylated forms of the high molecular weight neurofilament subunit (NF-H) was absent until the third day after differentiation. Immunoblot analyses confirmed that these alterations reflected specific changes in Vm and NF-H steady-state levels. Metabolic labeling demonstrated a decrease in the rate of Vm synthesis by the third day of differentiation. We conclude that changes in incorporation of intermediate filament species into the axonal cytoskeleton reflect distinct stages in neurite outgrowth and maturation; i.e., the Vm filament system may participate in initial stages of neuritogenesis during which outgrowth is most rapid, while NFPs may subsequently function in the establishment of a stabilized axonal cytoskeleton.
在小鼠NB2a/dl神经母细胞瘤细胞分化过程中，对波形蛋白（Vm）在不溶于曲拉通的细胞骨架中的定位进行了表征。在分化的第一天，神经突内的Vm染色增加，然后在胞体和神经突中迅速下降。相比之下，直到分化后第三天，才出现针对高分子量神经丝亚基（NF-H）广泛磷酸化形式的免疫反应性。免疫印迹分析证实，这些变化反映了Vm和NF-H稳态水平的特定变化。代谢标记显示，到分化第三天，Vm的合成速率下降。我们得出结论，中间丝种类纳入轴突细胞骨架的变化反映了神经突生长和成熟的不同阶段；即，Vm丝系统可能参与神经突发生的初始阶段，在此期间生长最为迅速，而神经丝蛋白可能随后在稳定轴突细胞骨架的建立中发挥作用。
