Specificity Protein 1 Transcription Factor Regulates Human ARTS Promoter Activity through Multiple Binding Sites

Eukaryotic topoisomerase II (topo II) catalyses topological genomic changes essential for chromosome segregation, chromatin reorganization, DNA replication and transcription. Mammalian topo II exists as two isoforms, designated α and β. Human topo IIα is an important cancer drug target, and an established determinant of drug sensitivity and resistance. Human topo IIβ is also the target of anticancer drugs but its role in drug resistance is less clear. The two human topo II proteins are encoded by the TOP2A and TOP2B genes, respectively, which despite their highly conserved structural organization, are subject to distinctly different modes of regulation. In the present study, we have cloned and characterized the human TOP2B promoter containing a 1.3kb fragment of the 5′-flanking and untranslated region (-1067 to +193). We found that the promoter activity of this TOP2B fragment was constant throughout the cell cycle, in contrast to the activity of the proximal promoter of TOP2A which was low in resting cells and enhanced during proliferation. Analyses of 5′-serially and internally deleted luciferase reporter constructs revealed that 80% of the TOP2B promoter activity could be attributed to the region between −533 and −481. Mutational analyses of putative regulatory elements indicated that two inverted CCAAT boxes (ICBs) within this region were essential for TOP2B promoter activity and gel mobility-shift assays indicated these sites bound the transcription factor nuclear factor-Y (NF-Y). Co-transfection experiments using a dominant-negative form of subunit A of NF-Y suggested that TOP2B promoter activity required direct interaction of NF-Y with the ICBs. In addition, a specificity protein-1 (Sp1)-binding GC box located just upstream of the ICBs was shown to contribute to TOP2B promoter activity in a synergistic manner with the ICBs. Our results suggest that the binding sites for NF-Y and Sp1 are critical for TOP2B transcription.

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Regulation of human CETP gene promoter activity: Role of multiple binding sites for SP1 and SP3 transcription factors

Atherosclerosis Supplements ◽

10.1016/s1567-5688(02)80390-7 ◽

2002 ◽

Vol 3 (2) ◽

pp. 149-150

Keyword(s):

Transcription Factors ◽

Binding Sites ◽

Promoter Activity ◽

Gene Promoter ◽

Multiple Binding Sites ◽

Multiple Binding

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Faculty Opinions recommendation of Multiple binding sites for the general anesthetic isoflurane identified in the nicotinic acetylcholine receptor transmembrane domain.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.5804956.5786054 ◽

2010 ◽

Author(s):

Edward Bertaccini

Keyword(s):

Acetylcholine Receptor ◽

Nicotinic Acetylcholine Receptor ◽

Binding Sites ◽

Transmembrane Domain ◽

General Anesthetic ◽

Nicotinic Acetylcholine ◽

Multiple Binding Sites ◽

Multiple Binding

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NMDAR PAMs: Multiple Chemotypes for Multiple Binding Sites

Current Topics in Medicinal Chemistry ◽

10.2174/1568026619666191011095341 ◽

2019 ◽

Vol 19 (24) ◽

pp. 2239-2253 ◽

Cited By ~ 2

Author(s):

Paul J. Goldsmith

Keyword(s):

Binding Sites ◽

Receptor Activation ◽

Research Area ◽

Allosteric Modulators ◽

Nonselective Cation Channels ◽

Multiple Binding Sites ◽

Multiple Binding ◽

Excitatory Neurotransmission ◽

Psychiatric Conditions ◽

High Level

The N-methyl-D-aspartate receptor (NMDAR) is a member of the ionotropic glutamate receptor (iGluR) family that plays a crucial role in brain signalling and development. NMDARs are nonselective cation channels that are involved with the propagation of excitatory neurotransmission signals with important effects on synaptic plasticity. NMDARs are functionally and structurally complex receptors, they exist as a family of subtypes each with its own unique pharmacological properties. Their implication in a variety of neurological and psychiatric conditions means they have been a focus of research for many decades. Disruption of NMDAR-related signalling is known to adversely affect higherorder cognitive functions (e.g. learning and memory) and the search for molecules that can recover (or even enhance) receptor output is a current strategy for CNS drug discovery. A number of positive allosteric modulators (PAMs) that specifically attempt to overcome NMDAR hypofunction have been discovered. They include various chemotypes that have been found to bind to several different binding sites within the receptor. The heterogeneity of chemotype, binding site and NMDAR subtype provide a broad landscape of ongoing opportunities to uncover new features of NMDAR pharmacology. Research on NMDARs continues to provide novel mechanistic insights into receptor activation and this review will provide a high-level overview of the research area and discuss the various chemical classes of PAMs discovered so far.

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Effects of Multiple Binding Sites on Studies of Hydrogen Bonding between Nitroxide Radicals and Solvent Molecules

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19930047 ◽

1993 ◽

Vol 58 (1) ◽

pp. 47-52 ◽

Cited By ~ 2

Author(s):

Imad Al-Bala'a ◽

Richard D. Bates

Keyword(s):

Hydrogen Bonding ◽

Magnetic Resonance ◽

Binding Site ◽

Binding Sites ◽

Hyperfine Coupling Constant ◽

Hydrogen Donor ◽

Complex Formation Constants ◽

Multiple Binding Sites ◽

Multiple Binding ◽

Solvent Molecules

The role of more than one binding site on a nitroxide free radical in magnetic resonance determinations of the properties of the complex formed with a hydrogen donor is examined. The expression that relates observed hyperfine couplings in EPR spectra to complex formation constants and concentrations of each species in solution becomes much more complex when multiple binding sites are present, but reduces to a simpler form when binding at the two sites occurs independently and the binding at the non-nitroxide site does not produce significant differences in the hyperfine coupling constant in the complexed radical. Effects on studies of hydrogen bonding between multiple binding site nitroxides and hydrogen donor solvent molecules by other magnetic resonance methods are potentially more extreme.

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