Drouva S V, Poulin B, Manceau V, Sobel A
CNRS UMR 6544, Université de la Méditerranée, Faculté de Médecine Nord, Bd Pierre Dramard, Marseille, France.
Endocrinology. 1998 May;139(5):2235-9. doi: 10.1210/endo.139.5.5995.
We have investigated the effects of GnRH (LHRH) and of the protein kinase C (PKC) activator 12-O-tetradecanoylphorbol-13-acetate on stathmin phosphorylation in the gonadotrope alphaT3-1 cell line. Stathmin expression and its phosphorylation were maximal during the exponential phase of cell growth. LHRH stimulated stathmin phosphorylation through a specific receptor in a dose- and time-dependent manner, and TPA induced a similar extensive stathmin phosphorylation. Their effects were inhibited either in PKC-depleted alphaT3-1 cells, or by the PKC inhibitor staurosporine. In the context of the known implication of PKC in LHRH-induced signal transduction, our results show that stathmin phosphorylation is involved in LHRH transduction, either as a result of direct activation of specific PKC isoforms or through a pathway involving kinases downstream to PKC activation.
我们研究了促性腺激素释放激素（GnRH，即黄体生成素释放激素，LHRH）和蛋白激酶C（PKC）激活剂12 - O - 十四酰佛波醇 - 13 - 乙酸酯对促性腺激素细胞αT3 - 1细胞系中微管蛋白磷酸化的影响。微管蛋白的表达及其磷酸化在细胞生长的指数期达到最大值。LHRH通过特定受体以剂量和时间依赖性方式刺激微管蛋白磷酸化，并且佛波酯（TPA）诱导了类似的广泛微管蛋白磷酸化。它们的作用在PKC缺失的αT3 - 1细胞中或被PKC抑制剂星形孢菌素抑制。鉴于已知PKC参与LHRH诱导的信号转导，我们的结果表明，微管蛋白磷酸化参与LHRH信号转导，这要么是特定PKC同工型直接激活的结果，要么是通过涉及PKC激活下游激酶的途径实现的。
