Electrophoretic characterization of nucleolar RNA from Chironomus tentans salivary gland cells

1970 ◽  
Vol 51 (2) ◽  
pp. 327-340 ◽  
Author(s):  
U. Ringborg ◽  
B. Daneholt ◽  
J.-E. Edström ◽  
E. Egyházi ◽  
B. Lambert
Keyword(s):  
Salivary Gland ◽  
Chironomus Tentans ◽  
Gland Cells ◽  
Salivary Gland Cells ◽  
Nucleolar Rna

Fractionation and characterization of rapidly phosphorylated nuclear proteins in salivary gland cells of Chironomus tentans

Chromosoma ◽  
1983 ◽  
Vol 88 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Endre Egyh�zi ◽  
Andrew Pigon ◽  
Mikael Holst ◽  
Lars Rydlander
Keyword(s):  
Salivary Gland ◽  
Nuclear Proteins ◽  
Chironomus Tentans ◽  
Gland Cells ◽  
Salivary Gland Cells

scholarly journals IN SITU DEMONSTRATION OF DNA HYBRIDIZING WITH CHROMOSOMAL AND NUCLEAR SAP RNA IN CHIRONOMUS TENTANS

1972 ◽  
Vol 53 (2) ◽  
pp. 407-418 ◽  
Author(s):  
B. Lambert ◽  
L. Wieslander ◽  
B. Daneholt ◽  
E. Egyházi ◽  
U. Ringborg
Keyword(s):  
Salivary Gland ◽  
Dna Sequences ◽  
Chironomus Tentans ◽  
Gland Cells ◽  
Salivary Gland Cells ◽  
Labeled Rna ◽  
Chromosome I ◽  
Nucleolar Rna ◽  
Diffuse Distribution

Cytological hybridization combined with microdissection of Chironomus tentans salivary gland cells was used to locate DNA complementary to newly synthesized RNA from chromosomes and nuclear sap and from a single chromosomal puff, the Balbiani ring 2 (BR 2). Salivary glands were incubated with tritiated nucleosides. The labeled RNA was extracted from microdissected nuclei and hybridized to denatured squash preparations of salivary gland cells under conditions which primarily allow repeated sequences to interact. The bound RNA, resistant to ribonuclease treatment, was detected radioautographically. It was found that BR 2 RNA hybridizes specifically with the BR 2 region of chromosome IV. Nuclear sap RNA was fractionated into high and low molecular-weight RNA; the former hybridizes with the BR 2 region of chromosome IV, the latter in a diffuse distribution over the whole chromosome set. RNA from chromosome I hybridizes diffusely with all chromosomes. Nucleolar RNA hybridizes specifically with the nucleolar organizers, contained in chromosomes II and III. It is concluded that the BR 2 region of chromosome IV contains repeated DNA sequences and that nuclear sap contains BR 2 RNA.

Microinjection of anti-topoisomerase I immunoglobulin G into nuclei of Chironomus tentans salivary gland cells leads to blockage of transcription elongation

1987 ◽  
Vol 7 (12) ◽  
pp. 4308-4316
Author(s):  
E Egyházi ◽  
E Durban
Keyword(s):  
Salivary Gland ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Immunoglobulin G ◽  
Topoisomerase I ◽  
Chironomus Tentans ◽  
Balbiani Ring ◽  
Gland Cells ◽  
Salivary Gland Cells ◽  
Transcriptional Process

Purified anti-topoisomerase I immunoglobulin G (IgG) was microinjected into nuclei of Chironomus tentans salivary gland cells, and the effect on DNA transcription was investigated. Synthesis of nucleolar preribosomal 38S RNA by RNA polymerase I and of chromosomal Balbiani ring RNA by RNA polymerase II was inhibited by about 80%. The inhibitory action of anti-topoisomerase I IgG could be reversed by the addition of exogenous topoisomerase I. Anti-topoisomerase I IgG had less effect on RNA polymerase II-promoted activity of other less efficiently transcribing heterogeneous nuclear RNA genes. The pattern of inhibition of growing nascent Balbiani ring chains indicated that the transcriptional process was interrupted at the level of chain elongation. The highly decondensed state of active Balbiani ring chromatin, however, remained unaffected after injection of topoisomerase I antibodies. These data are consistent with the interpretation that topoisomerase I is an essential component in the transcriptional process but not in the maintenance of the decondensed state of active chromatin.

scholarly journals Microinjection of anti-topoisomerase I immunoglobulin G into nuclei of Chironomus tentans salivary gland cells leads to blockage of transcription elongation.

1987 ◽  
Vol 7 (12) ◽  
pp. 4308-4316 ◽  
Author(s):  
E Egyházi ◽  
E Durban
Keyword(s):  
Salivary Gland ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Immunoglobulin G ◽  
Topoisomerase I ◽  
Chironomus Tentans ◽  
Balbiani Ring ◽  
Gland Cells ◽  
Salivary Gland Cells ◽  
Transcriptional Process

Purified anti-topoisomerase I immunoglobulin G (IgG) was microinjected into nuclei of Chironomus tentans salivary gland cells, and the effect on DNA transcription was investigated. Synthesis of nucleolar preribosomal 38S RNA by RNA polymerase I and of chromosomal Balbiani ring RNA by RNA polymerase II was inhibited by about 80%. The inhibitory action of anti-topoisomerase I IgG could be reversed by the addition of exogenous topoisomerase I. Anti-topoisomerase I IgG had less effect on RNA polymerase II-promoted activity of other less efficiently transcribing heterogeneous nuclear RNA genes. The pattern of inhibition of growing nascent Balbiani ring chains indicated that the transcriptional process was interrupted at the level of chain elongation. The highly decondensed state of active Balbiani ring chromatin, however, remained unaffected after injection of topoisomerase I antibodies. These data are consistent with the interpretation that topoisomerase I is an essential component in the transcriptional process but not in the maintenance of the decondensed state of active chromatin.

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