scholarly journals Human Synaptobrevin-like 1 Gene Basal Transcription Is Regulated through the Interaction of Selenocysteine tRNA Gene Transcription Activating Factor-Zinc Finger 143 Factors with Evolutionary Conserved Cis-elements

2003 ◽  
Vol 279 (9) ◽  
pp. 7734-7739 ◽  
Author(s):  
Francesca Di Leva ◽  
Maria Immacolata Ferrante ◽  
Francesca Demarchi ◽  
Antonella Caravelli ◽  
Maria Rosaria Matarazzo ◽  
...  
2004 ◽  
Vol 378 (2) ◽  
pp. 473-484 ◽  
Author(s):  
Stephan RYSER ◽  
Abbas MASSIHA ◽  
Isabelle PIUZ ◽  
Werner SCHLEGEL

Mitogen-activated protein kinases (MAPKs) are inactivated by a dual specificity phosphatase, MAPK phosphatase-1 (MKP-1). MKP-1 is transcribed as an immediate early response gene (IEG) following various stimuli. In the pituitary cell line GH4C1, MKP-1 gene transcription is strongly induced by thyrotropin-releasing hormone (TRH) as well as by epidermal growth factor (EGF) as a consequence of activated MAPK/extracellular-signal-regulated kinase (ERK) signalling. Intriguingly, reporter gene analysis with the MKP-1 promoter showed strong basal transcription, but only limited induction by TRH and EGF. Site-directed mutagenesis of the reporter construct combined with band-shift and in vivo studies revealed that part of the constitutive activity of the MKP-1 promoter resides in two GC boxes bound by Sp1 and Sp3 transcription factors in the minimal promoter. Basal transcription of transiently transfected luciferase reporter can be initiated by either of the two GC boxes or also by either of the two cAMP/Ca2+ responsive elements or by the E-box present in the proximal promoter. On the other hand, when analysed by stable transfection, the five responsive elements are acting in synergy to transactivate the MKP-1 proximal promoter. We show in this study that the MKP-1 promoter can function as a constitutive promoter or as a rapid and transient sensor for the activation state of MAPKs/ERKs. This dual mode of transcription initiation may have different consequences for the control of a block to elongation situated in the first exon of the MKP-1 gene, as described previously [Ryser, Tortola, van Haasteren, Muda, Li and Schlegel (2001) J. Biol. Chem. 276, 33319–33327].


2007 ◽  
Vol 44 (4) ◽  
pp. 311-321 ◽  
Author(s):  
Wafa Al-Kandari ◽  
Srikarthika Jambunathan ◽  
Vandana Navalgund ◽  
Rupa Koneni ◽  
Margot Freer ◽  
...  

1992 ◽  
Vol 47 (3-4) ◽  
pp. 320-322 ◽  
Author(s):  
Przemyslaw Szafranski ◽  
W. Jerzy Smagowicz

Abstract Apparent Michaelis constants for nucleotides in transcription of yeast tRN Agene by hom ologous RNA polymerase III with auxiliary protein factors, were found to be remarkably higher in initiation than in elongation of RNA chain. This supports presumptions regarding topological similarities between catalytic centers of bacterial and eukaryotic RNA polymerases.


2003 ◽  
Vol 17 (7) ◽  
pp. 1175-1191 ◽  
Author(s):  
Chi Keung Cheng ◽  
Ruby L. C. Hoo ◽  
Billy K. C. Chow ◽  
Peter C. K. Leung

Abstract The wide distribution of GnRH-II and conservation of its structure over all vertebrate classes suggest that the neuropeptide possesses vital biological functions. Although recent studies have shown that the expression of the human GnRH-II gene is regulated by cAMP and estrogen, the molecular mechanisms governing its basal transcription remain poorly understood. Using the neuronal TE-671 and placental JEG-3 cells, we showed that the minimal human GnRH-II promoter was located between nucleotide −1124 and −750 (relative to the translation start codon) and that the untranslated exon 1 was important to produce full promoter activity. Two putative E-box binding sites and one Ets-like element were identified within the first exon, and mutational analysis demonstrated that these cis-acting elements functioned cooperatively to stimulate the human GnRH-II gene transcription. EMSAs, UV cross-linking, and Southwestern blot analyses indicated that the basic helix-loop-helix transcription factor AP-4 bound specifically to the two E-box binding sites, whereas an unidentified protein bound to the Ets-like element. The functional importance of AP-4 in controlling human GnRH-II gene transcription was demonstrated by overexpression of sense and antisense full-length AP-4 cDNAs. Taken together, our present data demonstrate a novel mechanism in stimulating basal human GnRH-II gene transcription mediated by cooperative actions of multiple regulatory elements within the untranslated first exon of the gene.


2003 ◽  
Vol 23 (19) ◽  
pp. 6958-6972 ◽  
Author(s):  
Ying Zhang ◽  
Maria L. Dufau

ABSTRACT Transcription of luteinizing hormone receptor (LHR) gene is activated by Sp1/Sp3 at two Sp1 sites and is repressed by nuclear orphan receptors EAR2 and EAR3 through a direct-repeat (DR) motif. To elucidate the mechanism of the orphan receptor-mediated gene repression, we explored the functional connection between the orphan receptors and Sp1/Sp3 complex, and its impact on the basal transcription machinery. The Sp1(I) site was identified as critical for the repression since its mutation reduced the inhibition by EAR2 and abolished the inhibition by EAR3. Cotransfection analyses in SL2 cells showed that both Sp1 and Sp3 were required for this process since EAR3 displayed a complete Sp1/Sp3-dependent inhibitory effect. Functional cooperation between Sp1 and DR domains was further supported by mutual recruitment of EAR3 and Sp1/Sp3 bound to their cognate sites. Deletion of EAR3 N-terminal and DNA-binding domains that reduced its interaction with Sp1 impaired its inhibitory effect on human LHR (hLHR) gene transcription. Furthermore, we demonstrate interaction of TFIIB with Sp1/Sp3 at the Sp1(I) site besides its association with EAR3 and the TATA-less core promoter region. Such interaction relied on Sp1 site-bound Sp1/Sp3 complex and adaptor protein(s) present in the JAR nuclear extracts. We further demonstrated that EAR3 specifically decreased association of TFIIB to the Sp1(I) site without interfering on its interaction with the hLHR core promoter. The C-terminal region of EAR3, which did not participate in its interaction with Sp1, was required for its inhibitory function and may affect the association of TFIIB with Sp1. Moreover, perturbation of the association of TFIIB with Sp1 by EAR3 was reflected in the reduced recruitment of RNA polymerase II to the promoter. Overexpression of TFIIB counteracted the inhibitory effect of EAR3 and activated hLHR gene transcription in an Sp1 site-dependent manner. These findings therefore indicate that TFIIB is a key component in the regulatory control of EAR3 and Sp1/Sp3 on the initiation complex. Such cross talk among EAR3, TFIIB, and Sp1/Sp3 reveals repression of hLHR gene transcription by nuclear orphan receptors is achieved via perturbation of communication between Sp1/Sp3 at the Sp1-1 site and the basal transcription initiator complex.


2010 ◽  
Vol 17 (8) ◽  
pp. 976-981 ◽  
Author(s):  
Vesna C Nguyen ◽  
Brett W Clelland ◽  
Darren J Hockman ◽  
Sonya L Kujat-Choy ◽  
Holly E Mewhort ◽  
...  

2019 ◽  
Vol 2 (3) ◽  
pp. e201800261 ◽  
Author(s):  
Richoo B Davis ◽  
Neah Likhite ◽  
Christopher A Jackson ◽  
Tao Liu ◽  
Michael C Yu

Protein arginine methylation is an important means by which protein function can be regulated. In the budding yeast, this modification is catalyzed by the major protein arginine methyltransferase Hmt1. Here, we provide evidence that the Hmt1-mediated methylation of Rpc31, a subunit of RNA polymerase III, plays context-dependent roles in tRNA gene transcription: under conditions optimal for growth, it positively regulates tRNA gene transcription, and in the setting of stress, it promotes robust transcriptional repression. In the context of stress, methylation of Rpc31 allows for its optimal interaction with RNA polymerase III global repressor Maf1. Interestingly, mammalian Hmt1 homologue is able to methylate one of Rpc31’s human homologue, RPC32β, but not its paralogue, RPC32α. Our data led us to propose an efficient model whereby protein arginine methylation facilitates metabolic economy and coordinates protein-synthetic capacity.


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