caa a22 4500 47711881X CHVBK 20180405111630.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00250998 doi (NATIONALLICENCE)springer-10.1007/BF00250998 Effect of anthracycline antitumor antibiotics (adriamycin and nogalamyicin) and cycloheximide on the biosynthesis and processing of major UsnRNAs [Elektronische Daten] [Rabindranath Ray, Bimal Chakraborty, Kaushik Ray, Sheela Mukherji, Jayasree Chowdhury, Chinmay Panda] In the present study, anthracycline antitumor antibiotics (e.g. adriamycin and nogalamycin), the potent RNA synthesis inhibitors and cycloheximide, the protein synthesis inhibitor, have been used to understand the events of biosynthesis and processing of major UsnRNAs (U1-U6). The anthracyclines inhibit the UsnRNAs biosynthesis (in terms of labelling) differentially in a dose dependent manner. The inhibitory effect of adriamycin and nogalamycin reached plateau at a concentration of 2.5 μg/106 cells/ml and 0.1 μg/106 cells/ml respectively and indicates that nogalamycin is more inhibitory than adriamycin. The inhibition of the UsnRNAs synthesis (in terms of labelling) became maximum within 30 min of incubation and remained unaltered even after 2 h. Thus, it shows that the anthracyclines preferentially inhibit the initiation of the UsnRNA genes' transcription as it has been seen in cases of other large RNAs' synthesis by some other laboratories. The higher inhibitory effect of the anthracyclines on the biosynthesis of U5 and U6 compared to other UsnRNAs indicates the presence of more binding sites on the U5 and U6 snRNA genes. In presence of the anthracyclines, there was high retention of cytoplasmic major pre-UsnRNAs/UsnRNAs which indicates that the elongation of the UsnRNA synthesis is probably impaired along with initiation; because for the proper processing of the pre-UsnRNAs, formation of the correct secondary structure of that pre-UsnRNA is necessary. Cycloheximide showed some differential effect on the pol 11 transcribed UsnRNAs (U1-U5) biosynthesis (in terms of labelling) however it has no effect on the pol III transcribed U6 snRNA. It implies that in the pol 11 transcribed UsnRNAs, some transacting labile factors, either activator or inhibitor, are involved. Whereas, the processing of the UsnRNAs (either pol II or pol III transcribed) was affected more or less in a similar fashion in presence of cycloheximide, indicating the involvement of some transacting labile factors in this event. Kluwer Academic Publishers, 1996 anthracyclines nationallicence cycloheximide nationallicence UsnRNAs nationallicence biosynthesis and processing nationallicence Ray Rabindranath Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Chakraborty Bimal Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Ray Kaushik Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Mukherji Sheela Department of Biophysics, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Chowdhury Jayasree Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Panda Chinmay Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www/wkap.nl 162/1(1996-03-01), 75-82 0300-8177 162:1<75 1996 162 11010 https://doi.org/10.1007/BF00250998 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00250998 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ray Rabindranath Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 700 1- Chakraborty Bimal Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 700 1- Ray Kaushik Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 700 1- Mukherji Sheela Department of Biophysics, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 700 1- Chowdhury Jayasree Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 700 1- Panda Chinmay Department of Biochemistry, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, 700 026, Calcutta, India aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www/wkap.nl 162/1(1996-03-01), 75-82 0300-8177 162:1<75 1996 162 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer