Farnesyl transferase inhibitors block the farnesylation of CENP-E and CENP-F and alter the association of CENP-E with the microtubules.
Human tumor cell lines that are sensitive to the effects of farnesyl transferase inhibitors accumulate in G(2) --> M (except for cells with an activated Ha-ras that accumulate in G(1)). A search for CAAX box proteins from Swiss-Prot revealed more than 300 peptides. Of these, the centromeric proteins CENP-E and CENP-F are preferentially expressed during mitosis and are implicated as mediators of the G(2) --> M checkpoint. Experiments performed here show that peptides from the COOH-terminal CAAX box of CENP-E and CENP-F are substrates for farnesyl transferase but not geranylgeranyl transferase-I. Although both proteins are prenylated in the human tumor cell line DLD-1, their prenylation is completely inhibited by the farnesyl transferase inhibitor, SCH 66336. Immunohistochemical data with the lung carcinoma cell line, A549, showed that preventing the farnesylation of CENP-E and CENP-F by treatment with the farnesyl transferase inhibitor SCH 66336 does not affect their localization to the kinetochores. However, the presence of farnesyl transferase inhibitors alters the association between CENP-E and the microtubules. Our results imply that the inhibition of CENP-E farnesylation results in the alteration of the microtubule-centromere interaction during mitosis and results in the accumulation of cells prior to metaphase.
Ashar
H R
HR
Department of Tumor Biology, Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA.
James
L
L
Gray
K
K
Carr
D
D
Black
S
S
Armstrong
L
L
Bishop
W R
WR
Kirschmeier
P
P
D019883:Alkyl and Aryl Transferases / Q000037:antagonists & inhibitors*; D002453:Cell Cycle / Q000187:drug effects; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D008798:Mevalonic Acid / Q000378:metabolism; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D010880:Piperidines / Q000494:pharmacology; D017368:Protein Prenylation; D011725:Pyridines / Q000494:pharmacology; D013379:Substrate Specificity; D014407:Tumor Cells, Cultured; D003986:Dibenzocycloheptenes
D019883:Alkyl and Aryl Transferases; D002868:Chromosomal Proteins, Non-Histone; D004791:Enzyme Inhibitors; D008798:Mevalonic Acid; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins; D010880:Piperidines; D011725:Pyridines; C068688:centromere protein E; C094772:centromere protein F; C064911:p21(ras) farnesyl-protein transferase; C115354:lonafarnib; D003986:Dibenzocycloheptenes