Vincristine inhibition of DNA synthesis in Tetrahymena pyriformis.
نویسندگان
چکیده
The effect of vincristine sulfate (VCR)2 on the incorporation of isotopic precursors into protein, RNA, and DNA of the pro tozoan Tetrahymena pyriformis has been studied. DNA synthesis in logartithmically growing cells of T. pyriformi.s was almost completely inhibited by concentrations of VCR which only moderately depressed RNA and protein synthesis. Under ap propriate conditions this selective inhibition of DNA synthesis may be prevented by riboflavin or flavin mononucleotide. Flavin adenine dinucleotide was without effect.
منابع مشابه
Regulation of ribosomal RNA synthesis in Tetrahymena pyriformis.
Ribosomal RNA is synthesized at constant rate during most of the cell cycle in heat-shock synchronized populations of Tetrahymena pyriformis. Early in each macronuclear S-period the rate of synthesis increases abruptly, concomitant with replication of the genes coding for ribosomal RNA. The increase is prevented by inhibitors of DNA replication, added prior to the S-period. Similarly, in cultur...
متن کاملInhibition of rRNA synthesis following incorporation of 5-bromodeoxyuridine into DNA of Tetrahymena pyriformis.
Tetrahymena pyriformis was grown on chemically defined medium in the presence of 5-bromodeoxyuridine (BUdR). Under these growth conditions more than 60% of the thymidine sites in DNA were substituted with BUdR. It was found that RNA synthesis was strongly inhibited by the presence of BUdR in DNA. To assure that incorporation of BUdR into DNA was a prerequisite of the effect observed, BUdR was a...
متن کاملA NEW BIOLOGICAL SCREENING SYSTEM FOR LOCAL ANAESTHETICS BY INHIBITION MOBILITY OF TETRAHYMENA PYRIFORMIS
An alternative in vitro approach to drug screening has been the use of human cell cultures for antiviral agents and microbial cell cultures for the assessment of the carcinogenic potential of selected compounds. A number of protozoan species have been also used as drug screens for anti-protozoal agents. The ciliated protozoan Tetrahymena pyriformis species has been widely utilised as a dru...
متن کاملAccumulation of Replicative Intermediates of Mitochondrial Dna in Tetrahymena Pyriformis Grown in Ethidium Bromide
The effect of growth of Tetrahymena pyriformis in ethidium bromide (EthBr) on the structure and synthesis of mitochondrial DNA (mtDNA) has been investigated. During the first 5 h of growth in EthBr, mtDNA synthesis is inhibited 95% or more. After 10-15 h, this block is partially released and large numbers of replicating molecules accumulate, indicating that inhibition by EthBr primarily affects...
متن کاملMicronuclear Ribonucleic Acid in Tetrahymena Pyriformis
The presence of RNA in the micronucleus of Tetrahymena pyriformis was detected by electron microscope radioautography after incubation with tritiated precursors. The specificity of RNA labeling was shown by ribonuclease digestion. The period of appearance of labeled RNA in the micronucleus is approximately coincident with the DNA synthesis period for the micronucleus. Pulse-chase experiments sh...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Cancer research
دوره 26 4 شماره
صفحات -
تاریخ انتشار 1966