Yamane Takuya, Yamamoto Yoshio, Nakano Yoshihisa, Nakagaki Takenori, Ohkubo Iwao, Ariga Hiroyoshi
Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan.
Department of Ecology and Molecular Biology, Mie University, Iga, Mie 518-0131, Japan.
Biochem Biophys Res Commun. 2015 Nov 20;467(3):472-7. doi: 10.1016/j.bbrc.2015.10.032. Epub 2015 Oct 14.
Legumain (EC 3.4.22.34) is an asparaginyl endopeptidase. Strong legumain activity was observed in the mouse kidney, and legumain was highly expressed in tumors. We previously reported that bovine kidney annexin A2 was co-purified with legumain and that legumain cleaved the N-terminal region of annexin A2 at an Asn residue in vitro and in vivo. Recently, we found that transcription of the legumain gene is regulated by the p53 tumor suppressor in HCT116 cells. We and others reported that DJ-1/PARK7, a cancer- and Parkinson's disease-associated protein, works as a coactivator to various transcription factors, including the androgen receptor, p53, PSF, Nrf2, SREBP and RREB1. In this study, we found that expression levels of legumain mRNA and protein and legumain activity were increased in DJ-1-knockout cells. Furthermore, we found that DJ-1 binds to the p53-binding site on intron 1 of the mouse legumain gene in wild-type cells and that cleavage of annexin A2 was increased in DJ-1-knockout cells. These results suggest that legumain expression and activation and cleavage of annexin A2 are regulated by DJ-1 through p53.
天冬酰胺内肽酶（EC 3.4.22.34）是一种天冬酰胺基内肽酶。在小鼠肾脏中观察到强烈的天冬酰胺内肽酶活性，并且天冬酰胺内肽酶在肿瘤中高表达。我们之前报道过牛肾膜联蛋白A2与天冬酰胺内肽酶共纯化，并且天冬酰胺内肽酶在体外和体内均能在一个天冬酰胺残基处切割膜联蛋白A2的N端区域。最近，我们发现天冬酰胺内肽酶基因的转录在HCT116细胞中受p53肿瘤抑制因子调控。我们和其他人报道过，DJ-1/PARK7，一种与癌症和帕金森病相关的蛋白质，作为包括雄激素受体、p53、PSF、Nrf2、SREBP和RREB1在内的多种转录因子的共激活因子发挥作用。在本研究中，我们发现天冬酰胺内肽酶mRNA和蛋白的表达水平以及天冬酰胺内肽酶活性在DJ-1基因敲除细胞中升高。此外，我们发现DJ-1在野生型细胞中与小鼠天冬酰胺内肽酶基因内含子1上的p53结合位点结合，并且膜联蛋白A2的切割在DJ-1基因敲除细胞中增加。这些结果表明天冬酰胺内肽酶的表达、激活以及膜联蛋白A2的切割受DJ-1通过p53进行调控。
