Cell death in Tetrahymena thermophila: new observations on culture conditions

TY - JOUR

T1 - Cell death in Tetrahymena thermophila: new observations on culture conditions

AU - Christensen, S T

AU - Sørensen, H

AU - Beyer, N H

AU - Kristiansen, K

AU - Rasmussen, L

AU - Rasmussen, M I

N1 - Keywords: Animals; Apoptosis; Cell Division; Centrifugation; Culture Media; Dactinomycin; Microbiological Techniques; Oxygen; Plastics; Protein Synthesis Inhibitors; Signal Transduction; Swimming; Temperature; Tetrahymena thermophila

PY - 2001

Y1 - 2001

N2 - We previously suggested that the cell fate of the protozoan ciliate, Tetrahymena thermophila, effectively relates to a quorum-sensing mechanism where cell-released factors support cell survival and proliferation. The cells have to be present above a critical initial density in a chemically defined nutrient medium in order to release a sufficient level of these factors to allow a new colony to flourish. At a relatively high rate of metabolism and/or macromolecular synthesis and below this critical density, cells began to die abruptly within 30 min of inoculation, and this death took the form of an explosive disintegration lasting less than 50 milliseconds. The cells died at any location in the culture, and the frequency of cell death was always lower in well-filled vials than those with medium/air interface. Cell death was inhibited by the addition of Actinomycin D or through modifications of the culture conditions either by reducing the oxygen tension or by decreasing the temperature of the growth medium. In addition, plastic caps in well-filled vials release substances, which promote cell survival. The fate of low-density cultures is related to certain 'physical' conditions, in addition to the availability of oxygen within closed culture systems.

AB - We previously suggested that the cell fate of the protozoan ciliate, Tetrahymena thermophila, effectively relates to a quorum-sensing mechanism where cell-released factors support cell survival and proliferation. The cells have to be present above a critical initial density in a chemically defined nutrient medium in order to release a sufficient level of these factors to allow a new colony to flourish. At a relatively high rate of metabolism and/or macromolecular synthesis and below this critical density, cells began to die abruptly within 30 min of inoculation, and this death took the form of an explosive disintegration lasting less than 50 milliseconds. The cells died at any location in the culture, and the frequency of cell death was always lower in well-filled vials than those with medium/air interface. Cell death was inhibited by the addition of Actinomycin D or through modifications of the culture conditions either by reducing the oxygen tension or by decreasing the temperature of the growth medium. In addition, plastic caps in well-filled vials release substances, which promote cell survival. The fate of low-density cultures is related to certain 'physical' conditions, in addition to the availability of oxygen within closed culture systems.

U2 - 10.1006/cbir.2000.0689

DO - 10.1006/cbir.2000.0689

M3 - Journal article

C2 - 11407856

SN - 1065-6995

VL - 25

SP - 509

EP - 519

JO - Cell Biology International

JF - Cell Biology International

IS - 6

ER -