Transcriptional regulation of the legumain gene by p53 in HCT116 cells.
Legumain (EC 3.4.22.34) is an asparaginyl endopeptidase. Strong legumain activity was observed in the mouse kidney, and legumain was found to be 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. In this study, we found a p53-binding site in intron 1 of the human legumain gene using computational analysis. To determine whether transcription of the legumain gene is regulated by p53, HCT116 cells were transfected with p53 siRNA and the effect of knockdown of p53 expression on legumain expression was examined. The results showed that expression levels of both legumain mRNA and protein were decreased in the siRNA-treated cells. Furthermore, enzyme activity of legumain was also increased by doxorubicin and its activity was reduced by knockdown of p53 in HCT116 cells. These results suggest that legumain expression and its enzyme activity are regulated by p53.
Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan. t-yamane@pharm.hokudai.ac.jp
Takuya
T
Yamane
Sato
S
Murao
Izumi
I
Kato-Ose
Lisa
L
Kashima
Motoki
M
Yuguchi
Miyuki
M
Kozuka
Keisuke
K
Takeuchi
Hisakazu
H
Ogita
Iwao
I
Ohkubo
Hiroyoshi
H
Ariga
D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D003106:Colon / Q000187:drug effects / Q000378:metabolism; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000235:genetics* / Q000378:metabolism; D004317:Doxorubicin / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D045325:HCT116 Cells; D006801:Humans; D007438:Introns; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D015533:Transcriptional Activation; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D000099240:Asparaginyl Endopeptidase
D000903:Antibiotics, Antineoplastic; D003546:Cysteine Endopeptidases; D004317:Doxorubicin; D034741:RNA, Small Interfering; D016159:Tumor Suppressor Protein p53; D000099240:Asparaginyl Endopeptidase
DXR; Doxorubicin; Legumain; MCA; Z; benzyloxycarbonyl; doxorubicin; methylcumarinamide; p53