|Cancer||Cell death||Cell cycle||Cytoskeleton||Exo/endocytosis||Differentiation||Division||Organelles||Signalling||Stem cells||Trafficking|
Cell Biology International (1998) 22, 591598 (Printed in Great Britain)
STAUROSPORINE-INDUCED CELL DEATH INTETRAHYMENA THERMOPHILAHAS MIXED CHARACTERISTICS OF BOTH APOPTOTIC AND AUTOPHAGIC DEGENERATION
SØREN T. CHRISTENSENabc, JOHN CHEMNITZa, ELLEN M. STRAARUPa, KARSTEN KRISTIANSENb, DENYS N. WHEATLEYd and LEIF RASMUSSENa
aInstitute of Medical Biology, Department of Anatomy and Cell Biology, Odense University, Denmark
bDepartment of Molecular Biology, Odense University, Denmark
dCell Pathology Unit, University Medical School, Aberdeen, AB25 2ZD, Scotland, U.K.
cDepartment of Medical Biochemistry and Genetics, Biochemistry Laboratory B, University of Copenhagen, The Panum Institute, Blegdamsvej 3C, DK-2200, Copenhagen N, Denmark
Staurosporine blocks signal transduction associated with cell survival, proliferation and chemosensory behaviour in the ciliated protozoan,Tetrahymena thermophila. Staurosporine inhibits cell proliferation andin vivoprotein phosphorylation induced by phorbol ester. It also reduces thein vitrophosphorylation of the PKC-specific substrate, myelin basic protein fragment 4-14. Our results show that cell death in the presence of staurosporine is associated with morphological and ultrastructural changes similar to both apoptosis and autophagic degeneration, but these in turn can be postponed or prevented by 8-bromo-cyclic GMP, protoporphyrin IX, hemin or actinomycin D, although phorbol ester and insulin were ineffective. The results support the notion that staurosporine-induced cell death is an active process, associated with and/or requiringde novoRNA synthesis.
Key words: Tetrahymena thermophila, signalling, death, survival, proliferation, staurosporine, actinomycin D, programmed cell death, autophagic degeneration, apoptosis.
Received 21 August 1998; accepted 24 September 1998doi:10.1006/cbir.1998.0320