Xiao H, Hasegawa T, Miyaishi O, Ohkusu K, Isobe K i
Department of Basic Gerontology, National Institute for Longevity Sciences, 36-3 Gengo, Morioka-Cho, Obu, Japan.
Biochem Biophys Res Commun. 1997 Aug 18;237(2):457-60. doi: 10.1006/bbrc.1997.7158.
Sodium butyrate, a histone deacetylase inhibitor, has been shown to induce differentiation of many cancer cells and senescence-like state of human fibroblasts. Here we show that sodium butyrate also induces senescence-like state of NIH3T3 cells. The treated cells were blocked at G1 phase and featured morphologically like senescent cells with enlarged cytoplasm and multiple nuclei. The expression of p21(WAF/CIP1) (p21) increased after sodium butyrate treatment at transcriptional level. To analyze the induction of promoter activity, we isolated 4.6 kb of murine p21 promoter and inserted it upstream of a luciferase reporter gene. When this construct was transiently transfected into NIH3T3 cells, sodium butyrate enhanced the luciferase activity. p53 independency of sodium butyrate-inducible p21 promoter activity was confirmed by using the deletion mutants lacking p53 binding sites and p53 deficient cells in transfection experiments.
丁酸钠是一种组蛋白去乙酰化酶抑制剂，已被证明可诱导多种癌细胞分化以及人成纤维细胞进入衰老样状态。在此我们表明，丁酸钠还可诱导NIH3T3细胞进入衰老样状态。经处理的细胞停滞于G1期，形态上类似衰老细胞，细胞质增大且多核。丁酸钠处理后，p21（WAF/CIP1）（p21）的表达在转录水平上增加。为分析启动子活性的诱导情况，我们分离出4.6 kb的小鼠p21启动子，并将其插入荧光素酶报告基因的上游。当该构建体瞬时转染到NIH3T3细胞中时，丁酸钠增强了荧光素酶活性。通过在转染实验中使用缺失p53结合位点的缺失突变体和p53缺陷细胞，证实了丁酸钠诱导的p21启动子活性不依赖p53。
