Department of Biological Sciences, College of Pharmacy, Touro University of California, Mare Island, Vallejo, USA.
J Gerontol A Biol Sci Med Sci. 2011 Jul;66(7):723-31. doi: 10.1093/gerona/glr033. Epub 2011 Jun 2.
Senescent cells exhibit altered expression of numerous genes. Identifying the significance of the changes in gene expression may help advance our understanding of the senescence biology. Here, we report on the consistent and strong upregulation of CST1 expression during cellular senescence, independent of the initial trigger. CST1 expression at both the messenger RNA and protein levels was barely detected in control cells, which included early passage proliferating, quiescent, or immortal human fibroblasts and various human tumor cell lines. Immunoblotting and immunofluorescence cytochemical studies further suggest that CST1 accumulates intracellularly, within vesicular structures. We discuss these results in light of the known function of CST1 as a potent inhibitor of lysosomal cysteine proteases.
衰老细胞表现出许多基因表达的改变。鉴定基因表达变化的意义可能有助于我们深入了解衰老生物学。在这里，我们报告 CST1 表达在细胞衰老过程中一致且强烈地上调，而与初始触发因素无关。在对照细胞中，包括早期传代增殖、静止或永生化的人成纤维细胞和各种人肿瘤细胞系，几乎检测不到 CST1 的信使 RNA 和蛋白质水平的表达。免疫印迹和免疫荧光细胞化学研究进一步表明，CST1 在内含体样囊泡结构中积累。我们根据 CST1 作为溶酶体半胱氨酸蛋白酶的有效抑制剂的已知功能讨论了这些结果。
