Disease relevance of Activator Appliances

• We describe a mutant lambda phage repressor that has specifically lost its activator function [1].
• The X protein (HBx) of the human Hepatitis B Virus (HBV) is a regulatory protein that exercises a transcriptional activator function on a variety of regulatory elements and is therefore considered to be involved in the development of human hepatocellular carcinoma (HCC) [2].

High impact information on Activator Appliances

• Further, the readout of Shh activator function integrated over time and space does not display a stable and linear gradient along the A-P axis, as in a classical morphogen view [3].
• These results show that clr4 plays a critical role in silencing at mating-type loci and centromeres through the organization of repressive chromatin structure and demonstrate a new, activator function for Clr4p [4].
• Towards an understanding of the basis for activator function, including the multiplicity of TBP interactions, we have now identified mutations in yeast TBP that selectively block activator (GAL4-VP16)-dependent but not basal transcription [5].
• We show that activators function during at least two stages of preinitiation complex assembly: first, to recruit the general transcription factor TFIIB, and then at a second step, after TFIIB entry [6].
• These results reveal that selectivity in activator function in vivo can be achieved through differential use of TBP and TFIIB [7].

Biological context of Activator Appliances

• We discuss the dominant phenotype of C1-I with respect to its possible repressor function in contrast to the activator function of the C1 gene product [8].
• Taken together, we suggest that CTM alleviates repression by CE2, which allows HSF to be heat-inducibly phosphorylated and presume that phosphorylation is a prerequisite for the activator function of HSF when it binds to an atypical HSE [9].
• Evidence for a direct role for NGG1p in regulating activator function is supported by the finding that NGG1p is also required for transcriptional activation by GAL4p-VPl6 and LexA-GCN4p (Pina, B., Berger, S. L., Marcus, G. A., Silverman, N., Agapite, J., and Guarente, L. (1993) Mol. Cell. Biol. 13, 5981-5989) [10].
• We examined the interplay between DI, Gro and Dri on the hkb enhancer and show that when acting over a distance, Gro abolishes rather than converts DI activator function [11].
• Deletion of and point mutations in this CTD-like motif abolish the transcriptional activator function of the proline-rich domain, while natural CTD repeats from RNA polymerase II are fully functional in place of the CTD-like motif [12].

Anatomical context of Activator Appliances

• Recent studies have provided the first strong evidence for an instructive role: extracellular guidance cues can modulate Rho GTPase activities in vitro, and Rho GTPase activators function in growth cone guidance in vivo [13].
• As such, Gal4-final sigma(54) represents a novel tool with the potential to provide insight into the mechanism by which natural activators function in eukaryotic cells [14].

Associations of Activator Appliances with chemical compounds

• A nonantigenic covalent streptokinase-polyethylene glycol complex with plasminogen activator function [15].
• These data, which represent direct control of transcriptional activator function by a metabolite, are discussed in terms of the regulation of proline-specific genes in yeast and as a general mechanism of the control of transcription [16].
• We discuss how tyrosine phosphorylation, a very rare and highly significant regulatory modification, may control RIPE3b1 activator function [17].
• Mutations in basic residues of helix AH4 demonstrated the importance of the lysine K104 for the activator function of cGvpE [18].
• Mutations in the key residues of the putative leucine-zipper region AH6 of cGvpE confirmed that the three residues V159, L166 and L173 were essential for the activator function of cGvpE at the c-gvpA promoter, whereas the cysteine residue C180 could be altered to a leucine or an aspartate residue without the loss of this function [18].

Gene context of Activator Appliances

• Thus, Uaf30p plays only a minor role in its activator function [19].
• These data demonstrate that the products of the Pc-G genes can significantly repress activator function on transiently introduced DNA [20].
• We propose a model in which the ADA/GCN5 and SWI/SNF complexes facilitate activator function by acting in concert to disrupt or modify chromatin structure [21].
• These studies demonstrate that only the activator function of Gli2 is actually required, and indicates that in specific situations, Shh can modulate the ability of Gli1 to activate target genes [22].
• Our data, therefore, suggest that TFIIH and TFIIA can mediate activator function in the absence of TAFIIs [23].

References