Corrections - Adrenocorticotropic Hormone Regualtion of Adrenal RNA Poymerases. Stimulation of Nuclear RNA Polymerase III.

Biochemistry ◽  
1977 ◽  
Vol 16 (10) ◽  
pp. 2312-2312 ◽  
Author(s):  
Sheila Fuhrman ◽  
Gordon Gill
1987 ◽  
Vol 262 (1) ◽  
pp. 75-81
Author(s):  
R Reddy ◽  
D Henning ◽  
G Das ◽  
M Harless ◽  
D Wright

DNA Repair ◽  
2009 ◽  
Vol 8 (5) ◽  
pp. 620-626 ◽  
Author(s):  
M.C. Díaz de la Loza ◽  
R.E. Wellinger ◽  
A. Aguilera

AGE ◽  
1983 ◽  
Vol 6 (4) ◽  
pp. 106-112 ◽  
Author(s):  
Patricia Fitzpatrick-Dimond ◽  
John A. Todhunter ◽  
Sameeh S. Elridi

2016 ◽  
Author(s):  
Shrivani Sriskanthadevan-Pirahas ◽  
Rujuta Deshpande ◽  
Byoungchun Lee ◽  
Savraj S. Grewal

ABSTRACTThe small G-protein Ras is a conserved regulator of cell and tissue growth. These effects of Ras are mediated largely through activation of a canonical RAF-MEK-ERK kinase cascade. An important challenge is to identify how this Ras/ERK pathway alters cellular metabolism to drive growth. Here we report on stimulation of RNA polymerase III (Pol III)-mediated tRNA synthesis as a growth effector of Ras/ERK signalling in Drosophila. We find that activation of Ras/ERK signalling promotes tRNA synthesis both in vivo and in cultured Drosophila S2 cells. We also show that Pol III function is required for Ras/ERK signalling to drive proliferation in both epithelial and stem cells in Drosophila tissues. We find that the transcription factor Myc is required but not sufficient for Ras-mediated stimulation of tRNA synthesis. Instead we show that the main way that Ras promotes Pol III function and tRNA synthesis is by inhibiting the nuclear localization and function of the Pol III repressor Maf1. We propose that inhibition of Maf1 and stimulation of tRNA synthesis is one way by which Ras signalling enhances protein synthesis to promote cell and tissue growth.


1992 ◽  
Vol 12 (7) ◽  
pp. 3247-3261
Author(s):  
S Murphy ◽  
J B Yoon ◽  
T Gerster ◽  
R G Roeder

The promoters of both RNA polymerase II- and RNA polymerase III-transcribed small nuclear RNA (snRNA) genes contain an essential and highly conserved proximal sequence element (PSE) approximately 55 bp upstream from the transcription start site. In addition, the upstream enhancers of all snRNA genes contain binding sites for octamer-binding transcription factors (Octs), and functional studies have indicated that the PSE and octamer elements work cooperatively. The present study has identified and characterized a novel transcription factor (designated PTF) which specifically binds to the PSE sequence of both RNA polymerase II- and RNA polymerase III-transcribed snRNA genes. PTF binding is markedly potentiated by Oct binding to an adjacent octamer site. This potentiation is effected by Oct-1, Oct-2, or the conserved POU domain of these factors. In agreement with these results and despite the independent binding of Octs to the promoter, PTF and Oct-1 enhance transcription from the 7SK promoter in an interdependent manner. Moreover, the POU domain of Oct-1 is sufficient for significant in vitro activity in the presence of PTF. These results suggest that essential activation domains reside in PTF and that the potentiation of PTF binding by Octs plays a key role in the function of octamer-containing snRNA gene enhancers.


1994 ◽  
Vol 14 (3) ◽  
pp. 2021-2028 ◽  
Author(s):  
A Fantoni ◽  
A O Dare ◽  
C Tschudi

Transcription of U2 small nuclear RNA (snRNA) genes in eukaryotes is executed by RNA polymerase II and is dependent on extragenic cis-acting regulatory sequences which are not found in other genes. Here we have mapped promoter elements of the Trypanosoma brucei U2 snRNA gene by transient DNA expression of mutant constructs in insect form trypanosomes. Unlike other eukaryotic U2 snRNA genes, the T. brucei homolog is transcribed by an RNA polymerase III-like enzyme on the basis of its sensitivity to the inhibitors alpha-amanitin and tagetitoxin. Thus, the trypanosome U2 snRNA provides a unique example of an RNA polymerase III transcript carrying a trimethylated cap structure. The promoter of this gene consists of three distinct elements: an intragenic sequence close to the 5' end of the coding region, which is probably required to position the polymerase at the correct transcription start site; and two extragenic elements, located 110 and 160 nucleotides upstream, which are essential for U2 snRNA gene expression. These two elements closely resemble both in sequence and in distance from each other the A and B box consensus sequences of the internal control regions of tRNA genes.


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