RNA synthesis inhibitors

Tabata S, et al. Anti-tumor mechanisms of 3 -ethynyluridine and 3 -eth5mylcytidine as RNA synthesis inhibitors development and characterization of 3 -etyh5niyluri-dine-resistant cells. Cancer Lett 1997 116 225. 

Second, we evaluated the transcriptional rates of IL-8 in the presence or absence of EM by using a run-on transcription assay. EM clearly decreased the transcriptional rates of IL-8 mRNA. We evaluated the time course of IL-8 mRNA levels after treatment with actinomycin D, an RNA synthesis inhibitor there was no difference in the presence or absence of EM, showing that EM does not affect the decay speed of IL-8 mRNA. These findings indicated that EM suppresses IL-8 mRNA at the transcriptional levels. 

Thereafter, several compounds closely related to ircinins and variabilin have been isolated [5,6]. Fusetani and co-workers [34] reported the isolation of two compounds, dehydroderivative of ircinin (8) and an isomer of variabilin (9) from the Japanese sponge Cacospongia scalaris. Both compounds inhibited the cell division of fertilised starfish eggs at a concentration of 1.0 pg/ml. This assay is a variation on the test with sea urchin embryos, which can detect DNA and RNA synthesis inhibitors, microtubule assembly and protein synthesis inhibitors, the common leads... 

Protein and RNA synthesis inhibitors were subsequentially shown to rescue CNTF-, BDNF-and NGF-dependent neurons from apoptosis in vitro (Scott and Davies, 1990) and to reduce naturally occurring neuronal cell death in chick somatic motor and sensory neurons (Oppenheim et al., 1990). 

In the different models described above, apoptosis is triggered and mediated by different mechanisms. In some models, protein and RNA synthesis inhibitors rescue cells from death (Duke and Cohen 1986 Martin et al., 1988 Mesner et al.,... 

Corresponding variability in nuclear morphogenetic activity was demonstrated in later developmental stages and during postnatal ontogenesis, when the processes of cell and tissue specialization were complete. This was demonstrated for the differentiation of the crystalline lens (Reeder and Bell, 1965), muscle differentiation (Fieldman et al., 1964), hemopoiesis (Marx and Kovach, 1966), and early neuroem-bryogenesis (Akimova and Diban, 1967). The cortex of 1-5-day-oId newborn rats is sensitive to the injection of the RNA synthesis inhibitor actinomycin D. Under these conditions cortex development is slowed. Injection of actinomycin D after the fifth day postpartum does not affect development of 5-6 layers of cortex (Korochkin and Olenev, 1966 Korochkin, 1970). 

The hypothesis of a role for RNA in the establishment of memory has stimulated a number of experimental investigations of two types (1) the influence on memory of various compounds which disrupt RNA synthesis (inhibitors, base analogs), and physiological processes in the CNS (2) the influence of purified RNA on memory. 

Others RNA synthesis inhibitors, Peptidoglycan synthesis inhibitors Glycopeptides, Polypeptides, Rifamycins, Lipoglycopeptides and Tuberactinamycins... 

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