scholarly journals Presence and significance of a R110W mutation in the DNA-binding domain of GCM2 gene in patients with isolated hypoparathyroidism and their family members

2010 ◽  
Vol 162 (2) ◽  
pp. 407-421 ◽  
Author(s):  
Neeraj Tomar ◽  
Hema Bora ◽  
Ratnakar Singh ◽  
Nandita Gupta ◽  
Punit Kaur ◽  
...  
Keyword(s):  
Dna Binding ◽  
Nuclear Localization ◽  
Family Members ◽  
Binding Domain ◽  
Compound Heterozygous ◽  
Dna Binding Domain ◽  
Nucleotide Polymorphisms ◽  
Loss Of Function ◽  
Mobility Shift ◽  
Mobility Shift Assay

ObjectiveGlial cells missing 2 (GCM2) gene encodes a parathyroid-specific transcription factor. We assessed GCM2 gene sequence in patients with isolated hypoparathyroidism (IH).DesignCase–control study.MethodsComplete DNA sequencing of the GCM2 gene including its exons, promoter, and 5′ and 3′ UTRs was performed in 24/101 patients with IH. PCR–restriction fragment length polymorphism was used to detect a novel R110W mutation in all 101 IH patients and 655 healthy controls. Significance of the mutation was assessed by electrophoretic mobility shift assay (EMSA) and nuclear localization on transfection.ResultsA heterozygous R110W mutation was present in DNA-binding domain in 11/101 patients (10.9%) and absent in 655 controls (P<10−7). Four of 13 nonaffected first-degree relatives for five of these index cases had R110W mutation. Four heterozygous single nucleotide polymorphisms were found in the 5′ region. One of the 11 patients with R110W also had T370M change in compound heterozygous form. Mutant R110W and T370M GCM2 proteins showed decreased binding with GCM recognition elements on EMSA indicating loss of function. Both wild-type and R110W mutant GCM2 proteins showed nuclear localization.ConclusionsThe present study indicates a significant association of R110W variant with IH. Absence of effect of heterozygous R110W mutation on DNA binding and presence of the same mutation in asymptomatic family members indicate that additional genetic (akin to T370M change) or nongenetic factors might contribute to the expression of diseases in IH. Alternatively, it is possible that association of R110W with IH could be due to linkage disequilibrium with the unidentified relevant genes in IH.

scholarly journals Role of the IE62 Consensus Binding Site in Transactivation by the Varicella-Zoster Virus IE62 Protein

2010 ◽  
Vol 84 (8) ◽  
pp. 3767-3779 ◽  
Author(s):  
Kris White ◽  
Hua Peng ◽  
John Hay ◽  
William T. Ruyechan
Keyword(s):  
Dna Binding ◽  
Varicella Zoster Virus ◽  
Binding Site ◽  
Consensus Sequence ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Consensus Binding Site ◽  
Mobility Shift ◽  
Varicella Zoster ◽  
Mobility Shift Assay

ABSTRACT The varicella-zoster virus (VZV) IE62 protein is the major transcriptional activator. IE62 is capable of associating with DNA both nonspecifically and in a sequence-specific manner via a consensus binding site (5′-ATCGT-3′). However, the function of the consensus site is poorly understood, since IE62 efficiently transactivates promoter elements lacking this sequence. In the work presented here, sequence analysis of the VZV genome revealed the presence of 245 IE62 consensus sites throughout the genome. Some 54 sites were found to be present within putative VZV promoters. Electrophoretic mobility shift assay (EMSA) experiments using an IE62 fragment containing the IE62 DNA-binding domain and duplex oligonucleotides that did or did not contain the IE62 consensus binding sequence yielded KD (equilibrium dissociation constant) values in the nanomolar range. Further, the IE62 DNA binding domain was shown to have a 5-fold-increased affinity for its consensus site compared to nonconsensus sequences. The effect of consensus site presence and position on IE62-mediated activation of native VZV and model promoters was examined using site-specific mutagenesis and transfection and superinfection reporter assays. In all promoters examined, the consensus sequence functioned as a distance-dependent repressive element. Protein recruitment assays utilizing the VZV gI promoter indicated that the presence of the consensus site increased the recruitment of IE62 but not Sp1. These data suggest a model where the IE62 consensus site functions to down-modulate IE62 activation, and interaction of IE62 with this sequence may result in loss or decrease of the ability of IE62 to recruit cellular factors needed for full promoter activation.

scholarly journals Loss-of-function mutations in Zn-finger DNA-binding domain of HNF4A cause aberrant transcriptional regulation in liver cancer

Oncotarget ◽  
2018 ◽  
Vol 9 (40) ◽  
pp. 26144-26156 ◽  
Author(s):  
Hiroaki Taniguchi ◽  
Akihiro Fujimoto ◽  
Hidetoshi Kono ◽  
Mayuko Furuta ◽  
Masashi Fujita ◽  
...  
Keyword(s):  
Transcriptional Regulation ◽  
Dna Binding ◽  
Liver Cancer ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Loss Of Function

scholarly journals A single amino acid change in CUP2 alters its mode of DNA binding.

1990 ◽  
Vol 10 (9) ◽  
pp. 4778-4787 ◽  
Author(s):  
C Buchman ◽  
P Skroch ◽  
W Dixon ◽  
T D Tullius ◽  
M Karin
Keyword(s):  
Amino Acid ◽  
Dna Binding ◽  
Binding Activity ◽  
Binding Domain ◽  
Single Amino Acid ◽  
Dna Binding Domain ◽  
Sequence Motifs ◽  
Wild Type ◽  
Mobility Shift ◽  
Single Amino Acid Change

CUP2 is a copper-dependent transcriptional activator of the yeast CUP1 metallothionein gene. In the presence of Cu+ and Ag+) ions its DNA-binding domain is thought to fold as a cysteine-coordinated Cu cluster which recognizes the palindromic CUP1 upstream activation sequence (UASc). Using mobility shift, methylation interference, and DNase I and hydroxyl radical footprinting assays, we examined the interaction of wild-type and variant CUP2 proteins produced in Escherichia coli with the UASc. Our results suggest that CUP2 has a complex Cu-coordinated DNA-binding domain containing different parts that function as DNA-binding elements recognizing distinct sequence motifs embedded within the UASc. A single-amino-acid substitution of cysteine 11 with a tyrosine results in decreased Cu binding, apparent inactivation of one of the DNA-binding elements and a dramatic change in the recognition properties of CUP2. This variant protein interacts with only one part of the wild-type site and prefers to bind to a different half-site from the wild-type protein. Although the variant has about 10% of wild-type DNA-binding activity, it appears to be completely incapable of activating transcription.

Molecular genetics of chromosome translocations involving EWS and related family members

1999 ◽  
Vol 1 (3) ◽  
pp. 127-138 ◽  
Author(s):  
JUNGHO KIM ◽  
JERRY PELLETIER
Keyword(s):  
Transcription Factors ◽  
Dna Binding ◽  
Molecular Genetics ◽  
Family Members ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Chromosome Translocations ◽  
Amino Terminal ◽  
Terminal Domain ◽  
Related Family

Kim, Jungho, and Jerry Pelletier. Molecular genetics of chromosome translocations involving EWS and related family members. Physiol. Genomics 1: 127–138, 1999.—Many types of sarcomas are characterized by specific chromosomal translocations that appear to result in the production of novel, tumor-specific chimeric transcription factors. Many of these show striking similarities: the emerging picture is that the amino-terminal domain of the fusion product is donated by the Ewing's sarcoma gene ( EWS) or a related member from the same gene family, whereas the carboxy-terminal domain often consists of a DNA-binding domain derived from one of a number of transcription factors. Given the observation that the different translocation partners of the EWS protooncogene are associated with distinct types of sarcomas, the functional consequence of fusing EWS (or a related family member) to a different DNA-binding domain can only be understood in the context of functional studies that define the specificity of action of the different fusion products. An understanding of the molecular structure and function of these translocations provides new methods for diagnosis and novel targets for therapeutics.

scholarly journals A specific and unusual nuclear localization signal in the DNA binding domain of the Rev-erb orphan receptors

2003 ◽  
Vol 30 (2) ◽  
pp. 197-211 ◽  
Author(s):  
S Chopin-Delannoy ◽  
S Thenot ◽  
F Delaunay ◽  
E Buisine ◽  
A Begue ◽  
...  
Keyword(s):  
Amino Acid ◽  
Dna Binding ◽  
Fusion Protein ◽  
Nuclear Receptors ◽  
Nuclear Localization ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Protein Fusion ◽  
Orphan Receptors ◽  
Amino Terminal

The orphan receptors Rev-erbalpha and Rev-erbbeta are members of the nuclear receptors superfamily and act as transcriptional repressors. Rev-erbalpha is expressed with a robust circadian rhythm and is involved in liver metabolism through repression of the ApoA1 gene, but no role has been yet defined for Rev-erbbeta. To gain better understanding of their function and mode of action, we characterized the proteins encoded by these two genes. Both Rev-erbalpha and Rev-erbbeta proteins were nuclear when transiently transfected in COS-1 cells. The major nuclear location signal (NLS) of Rev-erbalpha is in the amino-terminal region of the protein. Fusion of green fluorescent protein (GFP) to the amino terminus of Rev-erbalpha deletion mutants showed that the NLS is located within a 53 amino acid segment of the DNA binding domain (DBD). The homologous region of Rev-erbbeta fused to GFP also targeted the fusion protein to the nucleus, suggesting that the location of this NLS is conserved among all the Rev-erb group members. Interestingly, members of the phylogenetically closest nuclear orphan receptor group (ROR), which exhibit 58% amino acid identity with Rev-erb in the DBD, do not have their NLS located within the DBD. GFP/DBD. RORalpha or GFP/DBD.RORbeta remained cytoplasmic, in contrast to GFP/DBD. Rev-erb fusion proteins. Alignment of human Rev-erb and ROR DBD amino acid sequences predicted that the two basic residues, K167 and R168, located just upstream from the second zinc finger, could play a critical part in the nuclear localization of Rev-erb proteins. Substitution of these two residues with those found in ROR, in the GFP/DBD. Rev-erb context, resulted in cytoplasmic proteins. In contrast, the reverse mutation of the GFP/DBD. RORalpha towards the Rev-erbalpha residues targeted the fusion protein to the nucleus. Our data demonstrate that Rev-erb proteins contain a functional NLS in the DBD. Its location is unusual within the nuclear receptor superfamily and suggests that Rev-erb orphan receptors control their intracellular localization via a mechanism different from that of other nuclear receptors.

Binding of the estrogen receptor DNA-binding domain to the estrogen response element induces DNA bending

1992 ◽  
Vol 12 (5) ◽  
pp. 2037-2042
Author(s):  
A M Nardulli ◽  
D J Shapiro
Keyword(s):  
Estrogen Receptor ◽  
Dna Binding ◽  
Dna Bending ◽  
Binding Domain ◽  
Estrogen Response Element ◽  
Dna Binding Domain ◽  
Mobility Shift ◽  
Response Element ◽  
Estrogen Response ◽  
Dna Fragment

We have used circular permutation analysis to determine whether binding of purified Xenopus laevis estrogen receptor DNA-binding domain (DBD) to a DNA fragment containing an estrogen response element (ERE) causes the DNA to bend. Gel mobility shift assays showed that DBD-DNA complexes formed with fragments containing more centrally located EREs migrated more slowly than complexes formed with fragments containing EREs near the ends of the DNA. DNA bending standards were used to determine that the degree of bending induced by binding of the DBD to an ERE was approximately 34 degrees. A 1.55-fold increase in the degree of bending was observed when two EREs were present in the DNA fragment. These in vitro studies suggest that interaction of nuclear receptors with their hormone response elements in vivo may result in an altered DNA conformation.

scholarly journals Smooth Muscle-Specific Genes Are Differentially Sensitive to Inhibition by Elk-1

2005 ◽  
Vol 25 (22) ◽  
pp. 9874-9885 ◽  
Author(s):  
Jiliang Zhou ◽  
Guoqing Hu ◽  
B. Paul Herring
Keyword(s):  
Smooth Muscle ◽  
Dna Binding ◽  
Binding Site ◽  
Serum Response Factor ◽  
Specific Protein ◽  
Binding Domain ◽  
Dominant Negative ◽  
Differential Sensitivity ◽  
Dna Binding Domain ◽  
Mobility Shift

ABSTRACT Understanding the mechanism of smooth muscle cell (SMC) differentiation will provide the foundation for elucidating SMC-related diseases, such as atherosclerosis, restenosis, and asthma. In the current study, overexpression of Elk-1 in SMCs down-regulated expression of several endogenous smooth muscle-restricted proteins, including telokin, SM22α, and smooth muscle α-actin. In contrast, down-regulation of endogenous Elk-1 in smooth muscle cells increased the expression of only telokin and SM22α, suggesting that smooth muscle-specific promoters are differentially sensitive to the inhibitory effects of Elk-1. Consistent with this, overexpression of the DNA binding domain of Elk-1, which acts as a dominant-negative protein by displacing endogenous Elk-1, enhanced the expression of telokin and SM22α without affecting expression of smooth muscle α-actin. Elk-1 suppressed the activity of smooth muscle-restricted promoters, including the telokin promoter that does not contain a consensus Elk-1 binding site, through its ability to block myocardin-induced activation of the promoters. Gel mobility shift and chromatin immunoprecipitation assays revealed that Elk-1 binds to a nonconsensus binding site in the telokin promoter and Elk-1 binding is dependent on serum response factor (SRF) binding to a nearby CArG box. Although overexpression of the SRF-binding B-box domain of Elk-1 is sufficient to repress the myocardin activation of the telokin promoter, this repression is not as complete as that seen with an Elk-1 fragment that includes the DNA binding domain. In addition, reporter gene assays demonstrate that an intact Elk-1 binding site in the telokin promoter is required for Elk-1 to maximally inhibit promoter activity. Together, these data suggest that the differential sensitivity of smooth muscle-specific genes to inhibition by Elk-1 may play a role in the complex changes in smooth muscle-specific protein expression that are observed under pathological conditions.

scholarly journals Phosphorylation of a Conserved Serine in the Deoxyribonucleic Acid Binding Domain of Nuclear Receptors Alters Intracellular Localization

2007 ◽  
Vol 21 (6) ◽  
pp. 1297-1311 ◽  
Author(s):  
Kai Sun ◽  
Vedrana Montana ◽  
Karthikeyani Chellappa ◽  
Yann Brelivet ◽  
Dino Moras ◽  
...  
Keyword(s):  
Dna Binding ◽  
Nuclear Receptors ◽  
Nuclear Localization ◽  
Thyroid Hormone Receptor ◽  
Zinc Fingers ◽  
Binding Domain ◽  
Retinoid X Receptor ◽  
Common Mechanism ◽  
Dna Binding Domain ◽  
Cytoplasmic Localization

Abstract Nuclear receptors (NRs) are a superfamily of transcription factors whose genomic functions are known to be activated by lipophilic ligands, but little is known about how to deactivate them or how to turn on their nongenomic functions. One obvious mechanism is to alter the nuclear localization of the receptors. Here, we show that protein kinase C (PKC) phosphorylates a highly conserved serine (Ser) between the two zinc fingers of the DNA binding domain of orphan receptor hepatocyte nuclear factor 4α (HNF4α). This Ser (S78) is adjacent to several positively charged residues (Arg or Lys), which we show here are involved in nuclear localization of HNF4α and are conserved in nearly all other NRs, along with the Ser/threonine (Thr). A phosphomimetic mutant of HNF4α (S78D) reduced DNA binding, transactivation ability, and protein stability. It also impaired nuclear localization, an effect that was greatly enhanced in the MODY1 mutant Q268X. Treatment of the hepatocellular carcinoma cell line HepG2 with PKC activator phorbol 12-myristate 13-acetate also resulted in increased cytoplasmic localization of HNF4α as well as decreased endogenous HNF4α protein levels in a proteasome-dependent fashion. We also show that PKC phosphorylates the DNA binding domain of other NRs (retinoic acid receptor α, retinoid X receptor α, and thyroid hormone receptor β) and that phosphomimetic mutants of the same Ser/Thr result in cytoplasmic localization of retinoid X receptor α and peroxisome proliferator-activated receptor α. Thus, phosphorylation of this conserved Ser between the two zinc fingers may be a common mechanism for regulating the function of NRs.

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