title: Single cell analysis of PKC activation during proliferation and apoptosis induced by laser irradiation.
abstract: Laser irradiation has been shown to trigger cellular proliferation and apoptosis in various cell types. Studying the signaling pathways involved in the laser irradiation is important for understanding these processes. In present study, to monitor the protein kinase Cs (PKCs) activity in living cells in real time, we transfected and screened human lung adenocarcinoma cells (ASTC-a-1) stably expressing C kinase activity reporter (CKAR) constructed based on fluorescence resonance energy transfer (FRET) technique. The CKAR is a specific, reversible reporter of phosphorylation by PKCs and it can monitor the ongoing balance between PKCs and phosphatases. The increasing dynamics of PKCs activity is monitored during cell proliferation induced by low-power laser irradiation (LPLI) (0.8 J/cm2) in serum-starved ASTC-a-1 cells stably expressing CKAR reporter using FRET imaging on laser scanning confocal microscope and using spectrofluorometric analysis on a luminescence spectrometer, respectively. However, the decreasing dynamics of PKCs activity has been monitored in real time using FRET imaging for the cells treated with high fluence LPLI (60 J/cm2), which was previously found to induce cell apoptosis. Taken together, LPLI induces the ASTC-a-1 cell proliferation by specifically activating PKCs. However, PKCs activity decreases during cell apoptosis induced by high fluence LPLI. Our results indicate that PKCs play an important role in the laser irradiation-induced biological effects.
authors.affiliation: Institute of Laser Life Science, South China Normal University, Guangzhou, China, and Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
authors.forename: Xuejuan
authors.initials: X
authors.lastname: Gao
authors.forename: Tongsheng
authors.initials: T
authors.lastname: Chen
authors.forename: Da
authors.initials: D
authors.lastname: Xing
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Yihui
authors.initials: Y
authors.lastname: Pei
authors.forename: Xunbin
authors.initials: X
authors.lastname: Wei
mesh_terms: D017209:Apoptosis / Q000528:radiation effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000528:radiation effects*; D004789:Enzyme Activation / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D028022:Low-Level Light Therapy; D008954:Models, Biological; D011493:Protein Kinase C / Q000378:metabolism* / Q000528:radiation effects*; D013050:Spectrometry, Fluorescence; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D013997:Time Factors; D014162:Transfection
chemical_list: D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate