TY - JOUR

T1 - Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

AU - Straarup, E M

AU - Schousboe, P

AU - Hansen, H Q

AU - Kristiansen, Karsten

AU - Hoffmann, Else Kay

AU - Rasmussen, L

AU - Christensen, S. T.

N1 - Keywords: Animals; Autoradiography; Croton Oil; Diglycerides; Electrophoresis, Polyacrylamide Gel; Enzyme Activation; Enzyme Inhibitors; Myelin Basic Proteins; Phosphorylation; Protein Kinase C; Staurosporine; Tetradecanoylphorbol Acetate; Tetrahymena thermophila

PY - 1997

Y1 - 1997

N2 - Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein kinase C activators phorbol 12-myristate 13-acetate (PMA) or 1-oleyl 2-acetate glycerol (OAG) when added to 250 cells ml-1 supported cell survival and proliferation. In the presence of the serine and threonine kinase inhibitor staurosporine the cells died both at 250 cells ml-1 in cultures supplemented with either PMA or OAG, or at 2,500 cells ml-1. At 500 cells ml-1 PMA induced the in vivo phosphorylation of at least six proteins. The myelin basic protein fragment 4-14 was phosphorylated in vitro in crude extracts of a culture of 250,000 cells ml-1. Both the in vivo and the in vitro phosphorylation were inhibited by staurosporine.

AB - Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein kinase C activators phorbol 12-myristate 13-acetate (PMA) or 1-oleyl 2-acetate glycerol (OAG) when added to 250 cells ml-1 supported cell survival and proliferation. In the presence of the serine and threonine kinase inhibitor staurosporine the cells died both at 250 cells ml-1 in cultures supplemented with either PMA or OAG, or at 2,500 cells ml-1. At 500 cells ml-1 PMA induced the in vivo phosphorylation of at least six proteins. The myelin basic protein fragment 4-14 was phosphorylated in vitro in crude extracts of a culture of 250,000 cells ml-1. Both the in vivo and the in vitro phosphorylation were inhibited by staurosporine.

M3 - Journal article

C2 - 9523425

VL - 91

SP - 181

EP - 190

JO - Microbios

JF - Microbios

SN - 0026-2633

IS - 368-369

ER -