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D D Moore

Publications and source records attributed to D D Moore.

At least 37 records · Page 2Linked to original sources
PubMed1999

Examining the relationship between gender and drug-using behaviors in adolescents: the use of diagnostic assessments and biochemical analyses of urine samples.

The present study examined the relationship between gender and drug-use among adolescents using diagnostic assessments and biochemical analyses of urine samples. The data were collected in the context of a referral and assessment program for adolescents suspected of using drugs, using the Adolescent Substance Battery [1]. A six-month random sample of 20 percent of adolescents assessed for drug use were targeted for biochemical assay. Compliance for urine delivery was relatively high at 91 percent. Urine samples were quantitatively screened for pharmaceuticals using a standard thin-layer chromatography (TLC) technique [2]. Statistical significance was found in the relationship between gender and marijuana use (p < .05). This study confirms that gender and drug-using behaviors among adolescents need additional research and evaluation.

Adolescent↗
PubMed1998

Androstane metabolites bind to and deactivate the nuclear receptor CAR-beta.

The orphan receptor CAR-beta binds DNA as a heterodimer with the retinoid-X receptor and activates gene transcription in a constitutive manner. Here we show that, in contrast to the classical nuclear receptors, the constitutive activity of CAR-beta results from a ligand-independent recruitment of transcriptional co-activators. While searching for potential ligands of CAR-beta, we found that the steroids androstanol and androstenol inhibit the constitutive activity of CAR-beta. This effect is stereospecific: only 3alpha-hydroxy, 5alpha-reduced androstanes are active. These androstanes do not interfere with heterodimerization or DNA binding of CAR-beta; instead, they promote co-activator release from the ligand-binding domain. These androstane ligands are examples of naturally occurring inverse agonists that reverse transcriptional activation by nuclear receptors. CAR-beta (constitutive androstane receptor-beta), therefore, defines an unanticipated steroidal signalling pathway that functions in a manner opposite to that of the conventional nuclear receptor pathways.

Androstanes↗
PubMed1998

Structure and expression of the orphan nuclear receptor SHP gene.

To determine the organization of the orphan nuclear receptor SHP gene (Seol, W., Choi, H.-S., and Moore, D.D. (1996) Science 272, 1336-1339), genomic clones were isolated from human and mouse genomic libraries. The SHP gene was composed of two exons interrupted by a single intron spanning approximately 1.8 kilobases in human and 1.2 kilobases in mouse. Genomic Southern blot analysis and fluorescence in situ hybridization of human metaphase chromosomes indicated that the SHP gene is located at the human chromosome 1p36.1 subband. The 5'-flanking regions of human and mouse SHP genes were highly conserved, showing 77% homology in the region of approximately 600 nucleotides upstream from the transcription start site. Primer extension analysis was carried out to determine the transcription start site of human SHP to 32 nucleotides downstream of a potential TATA box. The human SHP gene was specifically expressed in fetal liver, fetal adrenal gland, adult spleen, and adult small intestine. As expected from this expression pattern, the activity of the mouse SHP promoter measured by transient transfection was significantly higher in the adrenal-derived Y1 cells than HeLa cells.

Animals↗
PubMed1998

IkappaBbeta interacts with the retinoid X receptor and inhibits retinoid-dependent transactivation in lipopolysaccharide-treated cells.

To elucidate the molecular action of the NFkappaB inhibitor IkappaBbeta, we isolated a number of IkappaBbeta interactors using the yeast two-hybrid system. These include the retinoid X receptor (RXR), whose interaction with IkappaBbeta is significantly stimulated by the RXR ligand 9-cis-retinoic acid, as shown in the yeast system as well as the glutathione S-transferase pull down assays. RXR is a nuclear protein, whereas IkappaBbeta accumulates in the nucleus only in cells stimulated with lipopolysaccharide or other inducers that result in prolonged activation of NFkappaB. Consistent with this, cotransfection with IkappaBbeta specifically repressed the 9-cis-RA-induced transcriptional activities of RXR in an lipopolysaccharide-dependent manner. These results suggest a novel IkappaBbeta-mediated antagonism between the signaling pathways of NFkappaB and RXR.

Alitretinoin↗
PubMed1998

The Nuclear Receptor Resource: a growing family.

Last year, the original Glucocorticoid Receptor Resource was expanded into a comprehensive project: the Nuclear Receptor Resource (NRR, http:// nrr.georgetown.edu/nrr/nrr.html ). The NRR has since been offering comprehensive information on nuclear receptor structure and function, as well as general facts of interest to the scientific community on meetings, funding and employment opportunities. The project now includes individual resources as part of a network which integrates information on glucocorticoid, androgen, mineralocorticoid, thyroid hormone, Vitamin D and peroxisome-proliferator activated receptors. Many investigators have joined the NRR network by filling the Who is who? form available in the NRR home page. This has facilitated communication among scientists in the field and dissemination of data nor otherwise published. Because several investigators have contacted NRR authors over the past few months asking for advice and materials for educational purposes, we have recently decided to include in our project an educational resource on nuclear receptors termed the 'Graphics Library'. The input and suggestions of NRR users do shape the future direction of the project, so we encourage user to give us feedback.

Computer Communication Networks↗
PubMed1998

Alternative splicing variants of IkappaB beta establish differential NF-kappaB signal responsiveness in human cells.

To release transcription factor NF-kappaB into the nucleus, the mammalian IkappaB molecules IkappaB alpha and IkappaB beta are inactivated by phosphorylation and proteolytic degradation. Both proteins contain conserved signal-responsive phosphorylation sites and have conserved ankyrin repeats. To confer specific physiological functions to members of the NF-kappaB/Rel family, the different IkappaB molecules could vary in their specific NF-kappaB/Rel factor binding activities and could respond differently to activation signals. We have demonstrated that both mechanisms apply to differential regulation of NF-kappaB function by IkappaB beta relative to IkappaB alpha. Via alternative RNA processing, human IkappaB beta gives rise to different protein isoforms. IkappaB beta1 and IkappaB beta2, the major forms in human cells, differ in their carboxy-terminal PEST sequences. IkappaB beta2 is the most abundant species in a number of human cell lines tested, whereas IkappaB beta1 is the only form detected in murine cells. These isoforms are indistinguishable in their binding preferences to cellular NF-kappaB/Rel homo- and heterodimers, which are distinct from those of IkappaB alpha, and both are constitutively phosphorylated. In unstimulated B cells, however, IkappaB beta1, but not IkappaB beta2, is found in the nucleus. Furthermore, the two forms differ markedly in their efficiency of proteolytic degradation after stimulation with several inducing agents tested. While IkappaB beta1 is nearly as responsive as IkappaB alpha, indicative of a shared activation mechanism, IkappaB beta2 is only weakly degraded and often not responsive at all. Alternative splicing of the IkappaB beta pre-mRNA may thus provide a means to selectively control the amount of IkappaB beta-bound NF-kappaB heteromers to be released under NF-kappaB stimulating conditions.

Alternative Splicing↗
PubMed1998

Inhibition of estrogen receptor action by the orphan receptor SHP (short heterodimer partner).

SHP (short heterodimer partner) is an unusual orphan receptor that lacks a conventional DNA-binding domain. Previous results have shown that it interacts with several other nuclear hormone receptors, including the retinoid and thyroid hormone receptors, and inhibits their ligand-dependent transcriptional activation. Here we show that SHP also interacts with estrogen receptors and inhibits their function. In mammalian and yeast two-hybrid systems as well as glutathione-S-transferase pull-down assays, SHP interacts specifically with estrogen receptor-alpha (ERalpha) in an agonist-dependent manner. The same assay systems using various deletion mutants of SHP map the interaction domain with ERalpha to the same SHP sequences required for interaction with the nonsteroid hormone receptors such as retinoid X receptor and thyroid hormone receptor. In transient cotransfection assays, SHP inhibits estradiol -dependent activation by ERalpha by about 5-fold. In contrast, SHP interacts with ERbeta independent of ligand and reduces its ability to activate transcription by only 50%. These data suggest that SHP functions to regulate estrogen signaling through a direct interaction with ERalpha.

Estradiol↗
PubMed1997

Differential transactivation by two isoforms of the orphan nuclear hormone receptor CAR.

We have identified a new murine orphan member of the nuclear hormone receptor superfamily, termed mCAR, that is closely related to the previously described human orphan MB67, referred to here as hCAR. Like hCAR, mCAR expression is highest in liver. In addition to the most abundant mCAR1 isoform, the mCAR gene expresses a truncated mCAR2 variant that is missing the C-terminal portion of the ligand binding/dimerization domain. The mCAR gene has 8 introns, and this mCAR2 variant is generated by a splicing event that skips the 8th exon. mCAR1, like hCAR, binds as a heterodimer with the retinoid X receptor to the retinoic acid response element from the promoter of the retinoic acid receptor beta2 isoform. Consistent with its lack of a critical heterodimerization interface, the mCAR2 variant does not bind this site. Both mCAR1 and hCAR are apparently constitutive transcriptional activators. This activity is dependent on the presence of the conserved C-terminal AF-2 transcriptional activation motif. As expected from its inability to bind DNA, the mCAR2 variant neither transactivates by itself nor inhibits transactivation by hCAR or mCAR1.

Alternative Splicing↗
PubMed1997

Activation of the orphan receptor RIP14 by retinoids.

Retinoids are crucial regulators of a wide variety of processes in both developing and adult animals. These effects are thought to be mediated by the retinoic acid (RA) receptors and the retinoid X receptors (RXRs). We have identified an additional retinoid-activated receptor that is neither a retinoic acid receptors nor an RXR. RXR-interacting protein 14 (RIP14), a recently described orphan member of the nuclear receptor superfamily, can be activated by either all-trans-RA (tRA) or the synthetic retinoid TTNPB [[E]-4-[2-(5, 6, 7, 8-tetrahydro-5, 5, 8, 8-tetramethyl-2-naphthalenyl)propen-1-yl]benzoic acid].RIP14 binds to DNA as a heterodimer with RXR. In the presence of either tRA or TTNPB, the addition of 9-cis-RA or the RXR-specific agonist LG1069 [4-[1-(3, 5, 5, 8, 8-pentamethyl-5, 6, 7, 8-tertrahydro-2-naphthyl)ethenyl]benzoic acid] results in additional activation. Mutations of the ligand-dependent transcriptional activation functions indicate that TTNPB activates the RIP14 component of the RIP14-RXR heterodimer, that 9-cis-RA and LG1069 activate RXR, and that tRA activates via both RIP14 and RXR. Despite the very effective activation of RIP14 by tRA or TTNPB, relatively high concentrations of these compounds are required, and no evidence for direct binding of either compound was obtained using several approaches. These results suggest that RIP14 is the receptor for an as-yet-unidentified retinoid metabolite.

Animals↗
PubMed1997

The Nuclear Receptor Resource Project.

We have expanded the original Glucocorticoid Receptor Resource (GRR) database to include several individual resources as part of a larger project called the Nuclear Receptor Resource (NRR). In addition to the GRR, the NRR currently features the Thyroid Hormone Receptor Resource, the Androgen Receptor Resource, the Mineralocorticoid Receptor Resource, the Vitamin D Receptor Resource, and the Steroid Receptor Associated Proteins Resource. The goal of the NRR project is to provide a comprehensive resource for information on the nuclear receptor superfamily, and to provide a forum for the dissemination and discussion of both published and unpublished material on these proteins. Although the individual resources are managed from different servers, all the files are integrated and can be accessed through the project's Home Page, housed at http://nrr. georgetown.edu/nrr.html. In the near future, we hope to expand the project to contain information on other nuclear receptors and to better our electronic publication system. To accomplish this, we encourage the involvement of nuclear receptor investigators in the NRR.

Amino Acid Sequence↗
PubMed1997

Direct modulation of simian virus 40 late gene expression by thyroid hormone and its receptor.

Transcription of the late genes of simian virus 40 (SV40) is repressed during the early phase of the lytic cycle of infection of primate cells by the binding of cellular factors, called IBP-s, to the SV40 late promoter; repression is relieved after the onset of viral DNA replication by titration of these repressors (S. R. Wiley, R. J. Kraus, F. R. Zuo, E. E. Murray, K. Loritz, and J. E. Mertz, Genes Dev. 7:2206-2219, 1993). Recently, we showed that IBP-s consists of several members of the steroid/thyroid hormone receptor superfamily (F. Zuo and J. E. Mertz, Proc. Natl. Acad. Sci. USA 92:8586-8590, 1995). Here, we show that the thyroid hormone receptor TRalpha1, in combination with retinoid X receptor alpha (RXRalpha), is specifically bound at the transcriptional initiation site of the major late promoter of SV40. This binding repressed transcription from the SV40 late promoter by preventing the formation of pre-initiation complexes. Addition of the thyroid hormone 3,5,3'-L-triiodothyronine (T3) resulted in reversal of this repression in cotransfected CV-1 cells. Interestingly, repression did not occur when this thyroid response element (TRE) was translocated to 50 bp upstream of the major late initiation site. Binding of TRalpha1/RXRalpha heterodimers to this TRE induced bending of the promoter DNA. We conclude that hormones and their receptors can directly affect the expression of SV40, probably by affecting protein-protein and protein-DNA interactions involved in the formation of functional preinitiation complexes.

Animals↗
PubMed1997

Novel receptor interaction and repression domains in the orphan receptor SHP.

SHP (short heterodimer partner) is a novel orphan receptor that lacks a conventional DNA binding domain and interacts with other members of the nuclear hormone receptor superfamily. We have characterized the SHP sequences required for interaction with other superfamily members, and have defined an SHP repressor domain. In the mammalian two-hybrid system, a fusion of full-length SHP to the GAL4 DNA binding domain shows 9-cis-retinoic acid-dependent interaction with a VP16-retinoid X receptor alpha (RXR alpha) fusion. By deletion analysis, sequences required for this RXR interaction map to the central portion of SHP (amino acids 92 to 148). The same region is required for interaction with RXR in vitro and in the yeast two-hybrid system, and results from the yeast system suggest that the same SHP sequences are required for interaction with other members of the nuclear hormone receptor superfamily such as thyroid hormone receptor and retinoic acid receptor. In mammalian cells, a GAL4-SHP fusion protein shows about 10-fold-decreased transcriptional activation relative to GAL4 alone, and fusion of SHP to the C terminus of a GAL4-VP16 fusion to generate a triple chimera also results in a strong decrease in transactivation activity. Sequences required for this repressor function were mapped to the C terminus of SHP. This region is distinct from that required for corepressor interaction by other members of the nuclear hormone receptor superfamily, and SHP did not interact with N-CoR in either the yeast or mammalian two-hybrid system. Together, these results identify novel receptor interaction and repressor domains in SHP and suggest two distinct mechanisms for inhibition of receptor signaling pathways by SHP.

Amino Acid Sequence↗
PubMed1996

An orphan nuclear hormone receptor that lacks a DNA binding domain and heterodimerizes with other receptors.

SHP is an orphan member of the nuclear hormone receptor superfamily that contains the dimerization and ligand-binding domain found in other family members but lacks the conserved DNA binding domain. In the yeast two-hybrid system, SHP interacted with several conventional and orphan members of the receptor superfamily, including retinoid receptors, the thyroid hormone receptor, and the orphan receptor MB67. SHP also interacted directly with these receptors in vitro. In mammalian cells, SHP specifically inhibited transactivation by the superfamily members with which it interacted. These results suggest that SHP functions as a negative regulator of receptor-dependent signaling pathways.

Amino Acid Sequence↗
PubMed1996

A component of the 26S proteasome binds on orphan member of the nuclear hormone receptor superfamily.

The 26S proteasome complex plays a general role in turnover of both short and long lived proteins by specifically degrading ubiquitinated proteins. Recent evidence suggests that this large protease has more specific functions in a number of important cellular processes, ranging from activation of the transcription factor NFkB and antigen processing to transit through mitosis. We have identified a component of the 26S proteasome that interacts specifically with MB67, an orphan member of the nuclear hormone receptor superfamily. MIP224 (MB67 interacting protein) was isolated using the yeast two hybrid system and is apparently identical to the human 26S proteasome component TBP7. MIP224/TBP7 is one of several proteasomal proteins that share a strongly conserved ATPase domain (CAD) which is also present in a rapidly expanding superfamily of proteins with diverse functions. In yeast, MIP224 interacts specifically with MB67 and another closely related orphan receptor, but does not interact with several other receptor superfamily members tested. In mammalian cells, coexpression of MIP224 inhibits transactivation by MB67. MIP224 also interacts in yeast with other CAD proteins, including MSS1, which is proteasomal, and TRIP1, which is associated with transcriptional activation. This interaction of a proteasomal protein with a transcriptional protein suggests a previously unexpected link between the processes of protein degradation and transcriptional regulation.

ATPases Associated with Diverse Cellular Activitie↗
PubMed1996

Characterization and mapping of the Xiphophorus maculatus (Teleostei: Poeciliidae) RPS15 gene.

We have determined the nucleotide sequence and gene map location of the Xiphophorus maculatus homologue of RPS15 (ribosomal protein S15, alias RIG). The Xiphophorus RPS15 cDNA encodes 145 amino acids, which show 94% identity compared to deduced mammalian and avian RPS15 amino acid sequences. At the nucleotide level, 84% sequence identity is maintained between the fish and human gene, while homologous amphibian and avian sequences show about 80% nucleotide identity compared to the Xiphophorus sequence. Nucleotide identity substantially decreases when the fish gene is compared to Arabidopsis S15 (64%) and yeast S21 (55%) genes. Genetic linkage analysis of an RPS15 restriction fragment length polymorphism in backcross hybrids generated from the cross X. helleri x (X. maculatus Jp 163 B x X. helleri) demonstrated linkage of Xiphophorus RPS15 to the EGFR, UMPK and YES loci in Xiphophorus Linkage Group VI.

Amino Acid Sequence↗
PubMed1996

Two receptor interacting domains in the nuclear hormone receptor corepressor RIP13/N-CoR.

The thyroid hormone receptor (TR) and the retinoic acid receptor (RAR) act as transcriptional repressors when they are not occupied by their cognate ligands. This repressor function is mediated by proteins called corepressors. One of the nuclear hormone receptor corepressors, N-CoR, was originally isolated as a retinoid X receptor-interacting protein called RIP13. We have isolated a new potential variant of RIP13/N-CoR that is missing previously described transcriptional repressor domains but is similar in structure to the related corepressor termed SMRT or TRAC-2. Detailed analysis of the interaction with TR and RAR demonstrates that RIP13/N-CoR contains a new receptor interaction domain, termed ID-II, in addition to the previously described domain, referred to here as ID-I. Both ID-I and ID-II are capable of interacting independently with either TR or RAR, as assessed by the yeast two-hybrid system, by a mammalian two-hybrid system, or by direct in vitro binding. Results with all three approaches confirm that RIP13/N-CoR also interacts with retinoid X receptor, but this interaction is weaker than that with TR or RAR. Together, these results demonstrate that RIP13/N-CoR can interact with several different nuclear hormone receptors via two separate receptor interaction domains. Differences between the interactions observed in the different systems suggest that corepressor function may be modified by additional factors present in various cell types.

Amino Acid Sequence↗
PubMed1996

Early prevention of alcohol and other drug use among adolescents.

Among a variety of methods to prevent drug use among adolescents, school-community based prevention and intervention programs are prevalent. The impact of such programs will be compromised, however, if drug use among adolescents is impacted by forces apart from the impact of school-community prevention and intervention, such as the function of the family. On the other hand, prevention and intervention programs can have a powerful impact if teenage drug use is responded to through early intervention. The purpose of this study was to review a sample of students referred for drug assessments to determine how early intervention should occur and how involved high school and middle school students are with alcohol and other drugs.

Adolescent↗