scholarly journals TEAD/TEF transcription factors utilize the activation domain of YAP65, a Src/Yes-associated protein localized in the cytoplasm

2001 ◽  
Vol 15 (10) ◽  
pp. 1229-1241 ◽  
Author(s):  
A. Vassilev
2021 ◽  
Author(s):  
Chan Yul Yoo ◽  
Qing Sang ◽  
Jiangman He ◽  
Yongjian Qiu ◽  
Lingyun Long ◽  
...  

Phytochrome B (PHYB) triggers diverse light responses in Arabidopsis by binding to a group of antagonistically acting PHYTOCHROME-INTERACTING transcription FACTORs (PIFs) to promote PIF degradation, consequently downregulating PIF target genes. However, whether PHYB directly controls the transactivation activity of PIFs remains ambiguous. Here we show that the prototypic PIF, PIF3, possesses a p53-like transcription activation domain (TAD) consisting of a sequence-specific, hydrophobic activator motif surrounded by acidic residues. A PIF3mTAD mutant in which the activator motif is replaced with alanines fails to activate PIF3 target genes in Arabidopsis in dark, light, and shade conditions, validating the in vivo functions of the PIF3 TAD. Intriguingly, binding of the N-terminal photosensory module of PHYB to the PHYB-binding site adjacent to the TAD inhibits its transactivation activity. These results unveil a photoresponsive transcriptional switching mechanism in which photoactivated PHYB directly masks the transactivation activity of PIF3. Our study also suggests the unexpected conservation of sequence-specific TADs between the animal and plant kingdoms.


2004 ◽  
Vol 82 (4) ◽  
pp. 453-459 ◽  
Author(s):  
Alexandre M Erkine

Activation domains of promoter-specific transcription factors are critical entities involved in recruitment of multiple protein complexes to gene promoters. The activation domains often retain functionality when transferred between very diverse eukaryotic phyla, yet the amino acid sequences of activation domains do not bear any specific consensus or secondary structure. Activation domains function in the context of chromatin structure and are critical for chromatin remodeling, which is associated with transcription initiation. The mechanisms of direct and indirect recruitment of chromatin-remodeling and histone-modifying complexes, including mechanisms involving direct interactions between activation domains and histones, are discussed.Key words: activation domain, transcription, chromatin, nucleosome.


2006 ◽  
Vol 398 (3) ◽  
pp. 497-507 ◽  
Author(s):  
Yeon Sook Choi ◽  
Satrajit Sinha

The ESE (epithelium-specific Ets) subfamily of Ets transcription factors plays an important role in regulating gene expression in a variety of epithelial cell types. Although ESE proteins have been shown to bind to regulatory elements of some epithelial genes, the optimal DNA-binding sequence has not been experimentally ascertained for any member of the ESE subfamily of transcription factors. This has made the identification and validation of their targets difficult. We are studying ESE-2 (Elf5), which is highly expressed in epithelial cells of many tissues including skin keratinocytes. Here, we identify the preferred DNA-binding site of ESE-2 by performing CASTing (cyclic amplification and selection of targets) experiments. Our analysis shows that the optimal ESE-2 consensus motif consists of a GGA core and an AT-rich 5′- and 3′-flanking sequences. Mutational and competition experiments demonstrate that the flanking sequences that confer high DNA-binding affinity for ESE-2 show considerable differences from the known consensus DNA-binding sites of other Ets proteins, thus reinforcing the idea that the flanking sequences may impart recognition specificity for Ets proteins. In addition, we have identified a novel isoform of murine ESE-2, ESE-2L, that is generated by use of a hitherto unreported new exon and an alternate promoter. Interestingly, transient transfection assays with an optimal ESE-2 responsive reporter show that both ESE-2 and ESE-2L are weak transactivators. However, similar studies utilizing GAL4 chimaeras of ESE-2 demonstrate that while the DNA-binding ETS (E twenty-six) domain functions as a repressor, the PNT (pointed domain) of ESE-2 can act as a potent transcriptional activation domain. This novel transactivating property of PNT is also shared by ESE-3, another ESE family member. Identification of the ESE-2 consensus site and characterization of the transcriptional activation properties of ESE-2 shed new light on its potential as a regulator of target genes.


1993 ◽  
Vol 90 (23) ◽  
pp. 11361-11365 ◽  
Author(s):  
J D Licht ◽  
M Ro ◽  
M A English ◽  
M Grossel ◽  
U Hansen

The Krüppel (Kr) protein, bound at kilobase distances from the start site of transcription, represses transcription by RNA polymerase II in mammalian cells. Repression is monotonically dependent on the dose of Kr protein and the presence of Kr binding site(s) on the DNA. These data suggest an inhibitory protein-protein interaction between the Kr protein and proximal transcription factors. Repression by Kr depends on the specific activator protein driving transcription. In particular, Kr protein selectively represses transcription mediated by the Sp1 glutamine-rich activation domain, tethered to the promoter by a GAL4 DNA-binding domain, but does not repress transcription stimulated by the acidic GAL4 activator. We believe this represents repression by a quenching interaction between DNA-bound Kr protein and the activation region of Sp1, rather than competition between Sp1 and Kr for a limiting transcriptional component. Selective, context-related repression affords an added layer of combinatorial control of gene expression by sequence-specific transcription factors.


2012 ◽  
Vol 70 (5) ◽  
pp. 855-865 ◽  
Author(s):  
Shiv B. Tiwari ◽  
Alemu Belachew ◽  
Siu Fong Ma ◽  
Melinda Young ◽  
Jules Ade ◽  
...  

Development ◽  
2000 ◽  
Vol 127 (13) ◽  
pp. 2965-2976 ◽  
Author(s):  
A. Nasiadka ◽  
A. Grill ◽  
H.M. Krause

Homeodomain proteins are DNA-binding transcription factors that control major developmental patterning events. Although DNA binding is mediated by the homeodomain, interactions with other transcription factors play an unusually important role in the selection and regulation of target genes. A major question in the field is whether these cofactor interactions select target genes by modulating DNA binding site specificity (selective binding model), transcriptional activity (activity regulation model) or both. A related issue is whether the number of target genes bound and regulated is a small or large percentage of genes in the genome. In this study, we have addressed these issues using a chimeric protein that contains the strong activation domain of the viral VP16 protein fused to the Drosophila homeodomain-containing protein Fushi tarazu (Ftz). We find that genes previously thought not to be direct targets of Ftz remain unaffected by FtzVP16. Addition of the VP16 activation domain to Ftz does, however, allow it to regulate previously identified target genes at times and in regions that Ftz alone cannot. It also changes Ftz into an activator of two genes that it normally represses. Taken together, the results suggest that Ftz binds and regulates a relatively limited number of target genes, and that cofactors affect target gene specificity primarily by controlling binding site selection. Activity regulation then fine-tunes the temporal and spatial domains of promoter responses, the magnitude of these responses, and whether they are positive or negative.


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