Cafferata E G, González-Guerrico A M, Giordano L, Pivetta O H, Santa-Coloma T A
Instituto de Investigaciones Bioquímicas-Fundación Campomar (IIB, UBA, IIBBA, CONICET), Patricias Argentinas 435, 1405, Buenos Aires, Argentina.
Biochim Biophys Acta. 2000 Feb 21;1500(2):241-8. doi: 10.1016/s0925-4439(99)00105-2.
Cystic fibrosis is an autosomal recessive genetic disease, produced by a mutation in the CFTR gene that impairs its function as a chloride channel. In this work, we have examined the effects of interleukin-1beta (IL-1beta) on the expression of CFTR in human colonic T84 cells. Treatment of T84 cells with IL-1beta (0.25 ng/ml) for 4 h resulted in an increased CFTR expression (mRNA and protein). However, higher doses of IL-1beta (1 ng/ml and over) produced inhibition of CFTR mRNA and protein expression. The protein kinase C (PKC) inhibitors H7 (50 microM) and GF109203X (1 microM) inhibited the stimulatory effect of IL-1beta. Similar effects were seen in the presence of the protein tyrosine kinase (PTK) inhibitors genistein (60 microM) and herbymicin A (2 microM). These results suggest that some PKC isoform(s) and at least a PTK might be involved in the CFTR up-regulation induced by IL-1beta. The repression of CFTR up-regulation by cycloheximide (35.5 microM) suggests the participation of a de novo synthesized protein. Results obtained by using the RNA polymerase II inhibitor DRB (78 microM), suggest that the increased mRNA levels seen after IL-1beta treatment are not due to an increased stability of the message. We conclude that the CFTR mRNA and protein levels are modulated by IL-1beta, this cytokine being the first extracellular protein known to up-regulate CFTR gene expression.
囊性纤维化是一种常染色体隐性遗传病，由CFTR基因突变引起，该突变损害了其作为氯离子通道的功能。在本研究中，我们检测了白细胞介素-1β（IL-1β）对人结肠T84细胞中CFTR表达的影响。用IL-1β（0.25 ng/ml）处理T84细胞4小时导致CFTR表达增加（mRNA和蛋白质）。然而，更高剂量的IL-1β（1 ng/ml及以上）会抑制CFTR mRNA和蛋白质表达。蛋白激酶C（PKC）抑制剂H7（50 microM）和GF109203X（1 microM）抑制了IL-1β的刺激作用。在存在蛋白酪氨酸激酶（PTK）抑制剂染料木黄酮（60 microM）和赫伯霉素A（2 microM）的情况下也观察到了类似的效果。这些结果表明，某些PKC亚型和至少一种PTK可能参与了IL-1β诱导的CFTR上调。放线菌酮（35.5 microM）对CFTR上调的抑制作用表明有新合成的蛋白质参与。使用RNA聚合酶II抑制剂DRB（78 microM）获得的结果表明，IL-1β处理后mRNA水平的升高并非由于信息稳定性的增加。我们得出结论，CFTR mRNA和蛋白质水平受IL-1β调节，这种细胞因子是已知的第一种上调CFTR基因表达的细胞外蛋白质。
