Parrow V, Fagerström S, Meyerson G, Nånberg E, Påhlman S
Department of Pathology, University Hospital, Uppsala, Sweden.
J Neurosci Res. 1995 Aug 15;41(6):782-91. doi: 10.1002/jnr.490410609.
SH-SY5Y cells differentiate into neuronal-like cells and express marker proteins like growth-associated protein (GAP-43) and neuropeptide tyrosine when treated with a low concentration (16 nM) of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) in the presence of growth factors or serum. Both control and differentiated cells expressed protein kinase C-alpha (PKC-alpha), PKC-epsilon, and PKC-zeta as revealed by Western blot analyses, but the subcellular distribution of the three isoforms was not uniform, indicating specific localized functions of the enzymes. In growth cones prepared from differentiating cells PKC-alpha and PKC-epsilon were enriched. In contrast, PKC-zeta was more evenly distributed within the differentiating cell. Cells treated with a high concentration of TPA (1.6 microM) differentiate poorly and continue to proliferate. In those cells, PKC-alpha and PKC-epsilon were found to be down-regulated while PKC-zeta remained present. Thus, down-regulation of PKC-alpha and PKC-epsilon appears to be incompatible with neuronal differentiation of SH-SY5Y cells. These cells also differentiate when treated with a combination of basic fibroblast growth factor and insulin-like growth factor I. Growth cones isolated from such cells are also enriched in PKC-alpha and PKC-epsilon, but not in PKC-zeta. Based on the subcellular distribution of PKC-alpha and epsilon, and that PKC substrates like GAP-43 and pp60c-src are enriched in SH-SY5Y growth cones, a role during neurite growth is suggested.
在生长因子或血清存在的情况下，用低浓度（16 nM）的佛波酯12 - O - 十四酰佛波醇 - 13 - 乙酸酯（TPA）处理时，SH - SY5Y细胞会分化为神经元样细胞，并表达生长相关蛋白（GAP - 43）和神经肽酪氨酸等标记蛋白。蛋白质印迹分析显示，对照细胞和分化细胞均表达蛋白激酶C - α（PKC - α）、PKC - ε和PKC - ζ，但这三种亚型的亚细胞分布并不均匀，表明这些酶具有特定的局部功能。在由分化细胞制备的生长锥中，PKC - α和PKC - ε富集。相比之下，PKC - ζ在分化细胞内分布更为均匀。用高浓度TPA（1.6 μM）处理的细胞分化较差并继续增殖。在这些细胞中，发现PKC - α和PKC - ε被下调，而PKC - ζ仍然存在。因此，PKC - α和PKC - ε的下调似乎与SH - SY5Y细胞的神经元分化不相容。当用碱性成纤维细胞生长因子和胰岛素样生长因子I联合处理时，这些细胞也会分化。从此类细胞分离出的生长锥中PKC - α和PKC - ε也富集，但PKC - ζ不富集。基于PKC - α和ε的亚细胞分布，以及GAP - 43和pp60c - src等PKC底物在SH - SY5Y生长锥中富集的情况，提示其在神经突生长过程中发挥作用。
