Light-dependent induction of early-response gene expression by calphostin-C.
Calphostin-C is a compound possessing the ability to inhibit protein kinase C (PKC) by oxidative modification in vitro and to enhance the epidermal growth factor (EGF) receptor phosphorylation in vivo in a light-dependent manner. Here, we found that calphostin-C induced c-fos and c-jun mRNA accumulation in the lung adenocarcinoma cell line A549 in a light-dependent manner. Nuclear run-on assay revealed that this mRNA accumulation took place at the transcription level. However, unlike in vitro, calphostin-C did not inhibit cytosolic PKC activity in vivo, and the gene expression induced by calphostin-C was inhibited by another PKC inhibitor, staurosporine. Thus, it was suggested that calphostin-C activates cytosolic PKC-dependent signaling pathway to the induction of "early-response gene" expression in a light-dependent manner.
Gamou
S
S
Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan.
Shimizu
N
N
D000230:Adenocarcinoma / Q000235:genetics; D015152:Blotting, Northern; D066246:ErbB Receptors / Q000187:drug effects / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D016762:Genes, fos / Q000187:drug effects*; D016758:Genes, jun / Q000187:drug effects*; D006801:Humans; D008027:Light; D008175:Lung Neoplasms / Q000235:genetics; D009281:Naphthalenes; D010766:Phosphorylation; D011083:Polycyclic Compounds / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured
D009281:Naphthalenes; D011083:Polycyclic Compounds; D012333:RNA, Messenger; C061465:calphostin complex; D066246:ErbB Receptors