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Stanley Wang

Publications and source records attributed to Stanley Wang.

5 recordsLinked to original sources
PubMed2006

In vitro fluorescence anisotropy analysis of the interaction of full-length SRC1a with estrogen receptors alpha and beta supports an active displacement model for coregulator utilization.

Binding of full-length P160 coactivators to hormone response element-steroid receptor complexes has been difficult to investigate in vitro. Here, we report a new application of our recently described fluorescence anisotropy microplate assay to investigate binding and dissociation of full-length steroid receptor coactivator-1a (SRC1a) from full-length estrogen receptor alpha (ERalpha) or estrogen receptor beta (ERbeta) bound to a fluorescein-labeled (fl) estrogen response element (ERE). SRC1a exhibited slightly higher affinity binding to flERE.ERbeta than to flERE.ERalpha. Binding of SRC1a to flERE.ERalpha and to flERE.ERbeta was 17beta-estradiol (E2)-dependent and was nearly absent when ICI 182,780, raloxifene, or 4-hydroxytamoxifen were bound to the ERs. SRC1a binds to flERE.E2-ERalpha and flERE.E2-ERbeta complexes with a t1/2 of 15-20 s. Short LXXLL-containing nuclear receptor (NR) box peptides from P160 coactivators competed much better for SRC1a binding to flERE.E2-ER than an NR box peptide from TRAP220. However, approximately 40-250-fold molar excess of the P160 NR box peptides was required to inhibit SRC1a binding by 50%. This suggests that whereas the NR box region is a primary site of interaction between SRC1a and ERE.E2-ER, additional contacts between the coactivator and the ligand-receptor-DNA complex make substantial contributions to overall affinity. Increasing amounts of NR box peptides greatly enhanced the rate of dissociation of SRC1a from preformed flERE.E2-ER complexes. The data support a model in which coactivator exchange is facilitated by active displacement and is not simply the result of passive dissociation and replacement. It also shows that an isolated coactivator exhibits an inherent capacity for rapid exchange.

Amino Acid Sequence↗
PubMed2006

Analysis of RNA-protein interactions by a microplate-based fluorescence anisotropy assay.

Quantitative studies of RNA-protein interactions are quite cumbersome using traditional methods. We developed a rapid microplate-based fluorescence anisotropy (FA)/fluorescence polarization assay that works well, even with RNA probes >90 nucleotides long. We analyzed binding of RNA targets by vigilin/DDP1/SCP160p and by c-myc coding region instability determinant (CRD) binding protein, CRD-BP. Vigilin is essential for cell viability and functions in heterochromatin formation and mRNA decay. The CRD-BP stabilizes c-myc mRNA. Vigilin bound to a vitellogenin mRNA 3'-UTR probe with a two to three-fold lower affinity than to a Drosophila dodecasatellite ssDNA binding site and bound to the c-myc CRD with a two- to three-fold lower affinity than to the vitellogenin mRNA 3'-UTR. Competition between vigilin and CRD-BP for binding to the CRD may therefore play a role in regulating c-myc mRNA degradation. We analyzed suitability of the microplate-based FA assay for high-throughput screening for small-molecule regulators of RNA-protein interactions. The assay exhibits high reproducibility and precision and works well in 384-well plates and in 5 microl to 20 microl samples. To demonstrate the potential of this assay for screening libraries of small molecules to identify novel regulators of RNA-protein interactions, we identified neomycin and H33342 as inhibitors of binding of vigilin to the vitellogenin mRNA 3'-UTR.

3' Untranslated Regions↗
PubMed2006

Rural-urban disparities in health-related quality of life within disease categories of Veterans.

CONTEXT: Compared to their urban counterparts, rural veterans have been found to have lower health-related quality of life. PURPOSE: To determine whether these disparities persist when examining disease categories of rural and urban veterans. METHODS: We obtained survey data on 748,216 veterans who were current or anticipated Veterans Health Administration patients. Using International Classification of Diseases (ICD)-9CM codes, we determined whether these veterans had diagnoses that fell into any of 30 physical health disease categories, and we used ZIP codes to determine whether veterans lived in rural or urban settings. We compared rural to urban prevalence of disease categories as well as urban to rural health-related quality-of-life physical health component summary scores (PCS) and mental health component summary scores (MCS) for each disease category. FINDINGS: Physical diagnoses were significantly more prevalent in the rural veteran population for most disease categories examined. For every disease category examined, PCS were significantly lower for veterans who lived in rural, compared to urban, settings (P < .001 for all); rural veterans also experienced lower MCS for all disease categories although differences were modest. Differences persisted after controlling for sociodemographic factors. CONCLUSIONS: Compared to the urban veteran population, within disease categories, the rural veteran population experiences higher disease prevalence and lower physical and mental quality-of-life scores. Policymakers should anticipate greater health care demands from the rural veteran population and work to meet that demand.

Aged↗
PubMed2006

Rural and urban disparities in health-related quality of life among veterans with psychiatric disorders.

OBJECTIVE: The authors studied whether rural and urban disparities in health-related quality of life, demonstrated previously among veterans, persist among veterans with common psychiatric disorders. METHODS: A cohort of 748,216 users or anticipated users of Veterans Affairs services completed the Veterans Short Form Health Survey in 1999. From the survey, the authors determined health-related quality-of-life scores (physical [PCS] and mental [MCS] health component summaries) and used ICD-9-CM codes to identify veterans with six mental health disorders-depression, anxiety, posttraumatic stress disorder, alcohol dependence, schizophrenia, and bipolar disorder. With Rural-Urban Commuting Area codes to determine urban residency, the prevalence of psychiatric illness and health-related quality of life were compared across rural and urban groups. RESULTS: All psychiatric disorders except anxiety disorders not related to posttraumatic stress disorder were more prevalent in urban settings. However, rural veterans within mental illness cohorts had worse PCS and MCS scores. Differences in PCS scores were substantial, ranging between 2.27 for schizophrenia and 3.39 for alcohol dependence (p<.001 for all diagnoses). Differences in MCS scores were statistically significant but modest. In regression models, rural-urban disparities within psychiatric disorder cohorts persisted after sociodemographic factors were controlled for. CONCLUSIONS: Although less likely than their urban counterparts to have mental disorders, rural veterans with mental illness experienced a greater disease burden and were likely to incur greater health care costs. Improving access to mental health care for veterans in rural settings may narrow quality-of-life disparities among rural and urban veterans.

Adult↗