Protein synthesis and mitosis. 1. Influence of anti-tubulins on protein synthetic activity in synchronous M-phase and asynchronous populations of HeLa S-3 cells.
Asynchronous and synchronous HeLa S-3 suspension cultures treated with colcemid and vinblastine (VLB) resulted, in the former case, in suppression of 3H-leucine incorporation into protein which became increasingly apparent as the percentage of M-phase-arrested cells increased. In the latter case, where no cells were allowed to enter M-phase, no significant inhibition of incorporation occurred. M-phase cells were collected by shake-off from asynchronous monolayers, or alternatively monolayers presynchronised 10 h before shake-off, either in the presence or absence of alkaloids. In both cases, alkaloid-treated cultures showed marked inhibition of protein synthesis, while controls were largely unaffected. The results indicate that marked suppression of protein synthesis in alkaloid-arrested M-phase population is primarily due to the inability of cells to complete mitosis. Arrested cells showed no increase in size or protein content with time, but began disintegrating approximately 6-7 h after alkaloid treatment. The necessity for cells to traverse M-phase quickly is emphasised, otherwise any transient decline of protein synthesis during M-phase becomes grossly exaggerated.
Wheatley
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Cell Pathology Laboratory, Department of Pathology, Aberdeen, Scotland, Great Britain.
Glenesk
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A
Inglis
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MS
D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D002460:Cell Line; D003703:Demecolcine / Q000494:pharmacology*; D006367:HeLa Cells / Q000166:cytology; D006801:Humans; D008677:Metaphase / Q000187:drug effects*; D008938:Mitosis / Q000187:drug effects*; D014404:Tubulin / Q000096:biosynthesis*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D014747:Vinblastine / Q000494:pharmacology*
D000903:Antibiotics, Antineoplastic; D014404:Tubulin; D014747:Vinblastine; D003703:Demecolcine