Submitted to: Nature Magazine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 3, 1995
Publication Date: N/A
Interpretive Summary: Between one quarter and one third of all herbicides affect plant cell division (mitosis) as a primary mechanism of action. Recently, we have demonstrated that all these herbicides disrupt mitosis by interfering with the microtubules that separate chromosomes during cell division. Employing a transformed mammalian cell line, we show that, at elevated concentrations, two of the N-phenyl carbamate mitotic-disruptor herbicides interfere with mammalian microtubules as well.
Recent examination of oat seedlings indicate that the N-phenyl carbamate mitotic-disruptor herbicides are inhibitors of polymerization of plant tubulin into microtubules (Protoplasma 179:16-25). Only two of these compounds, propham and chlorpropham, have been tested for cytoskeletotoxicity on vertebrate cells or cytoskeletal components of vertebrate cells. We show that in human HeLa cells the N-phenyl carbamate herbicides carbetamide and propham do not disrupt mitosis at the highest concentrations tested (i.e. 800 and 400 uM, respectively), but chlorpropham and barban induce metaphase arrest at 300 and 30 uM, respectively, and inhibit growth by 50% at 150 and 7.5 uM, respectively).