The bromo-adjacent homology domains of PBRM1 associate with histone tails and contribute to PBAF-mediated gene regulation.

A critical component of gene regulation is recognition of histones and their post-translational modifications by transcription-associated proteins or complexes. Although many histone-binding reader modules have been characterized, the bromo-adjacent homology (BAH) domain family of readers is still poorly characterized. A pre-eminent member of this family is PBRM1 (BAF180), a component of the PBAF chromatin-remodeling complex. PBRM1 contains two adjacent BAH domains of unknown histone-binding potential. We evaluated the tandem BAH domains for their capacity to associate with histones and to contribute to PBAF-mediated gene regulation. The BAH1 and BAH2 domains of human PBRM1 broadly interacted with histone tails, but they showed a preference for unmodified N-termini of histones H3 and H4. Molecular modeling and comparison of the BAH1 and BAH2 domains with other BAH readers pointed to a conserved binding mode via an extended open pocket and, in general, an aromatic cage for histone lysine binding. Point mutants that were predicted to disrupt the interaction between the BAH domains and histones reduced histone binding in vitro and resulted in dysregulation of genes targeted by PBAF in cellulo. Although the BAH domains in PBRM1 were important for PBAF-mediated gene regulation, we found that overall chromatin targeting of PBRM1 was not dependent on BAH-histone interaction. Our findings identify a function of the PBRM1 BAH domains in PBAF activity that is likely mediated by histone tail interaction.

The Characteristics of People with Serious Mental Illness Who are at High Risk for Hospitalization or Death.

Many individuals with serious mental illness are at high risk for hospitalization or death due to inadequate treatment of medical conditions or unhealthy behaviors. The authors describe demographic and clinical characteristics associated with increased risk in this population. Electronic data were obtained for individuals in treatment at a large Veterans' healthcare system who were at high risk according to a validated model. A random sample of these individuals was assessed in person. Multivariable regressions estimated the effect of numerous demographic, health, and clinical characteristics on risk. Emergency visits and hospitalizations were common. Greater risk was associated with being male, not married, and having more diagnoses. While risk varied by race, this effect was no longer significant after controlling for other factors. Health-related quality of life worsened with increasing risk. Routine data identify a large population of high-risk individuals who may benefit from outreach to provide healthcare services.

Variation in benefit among patients with serious mental illness who receive integrated psychiatric and primary care.

PURPOSE: The population with serious mental illness has high risk for hospitalization or death due to unhealthy behaviors and inadequate medical care, though the level of risk varies substantially. Programs that integrate medical and psychiatric services improve outcomes but are challenging to implement and access is limited. It would be useful to know whether benefits are confined to patients with specific levels of risk. METHODS: In a population with serious mental illness and increased risk for hospitalization or death, a specialized medical home integrated services and improved treatment and outcomes. Treatment quality, chronic illness care, care experience, symptoms, and quality of life were assessed for a median of 385 days. Analyses examine whether improvements varied by baseline level of patient risk. RESULTS: Patients with greater risk were more likely to be older, more cognitively impaired, and have worse mental health. Integrated services increased appropriate screening for body mass index, lipids, and glucose, but increases did not differ significantly by level of risk. Integrated services also improved chronic illness care, care experience, mental health-related quality of life, and psychotic symptoms. There were also no significant differences by risk level. CONCLUSIONS: There were benefits from integration of primary care and psychiatric care at all levels of increased risk, including those with extremely high risk above the 95th percentile. When developing integrated care programs, patients should be considered at all levels of risk, not only those who are the healthiest.

Improved methods for the detection of histone interactions with peptide microarrays.

Histone post-translational modifications contribute to chromatin function largely through the recruitment of effector proteins that contain specialized "reader" domains. While a significant number of reader domains have been characterized for their histone binding specificities, many of these domains remain poorly characterized. Peptide microarrays have been widely employed for the characterization of histone readers, as well as modifying enzymes and histone antibodies. While powerful, this platform has limitations in terms of its sensitivity and they frequently miss low affinity reader domain interactions. Here, we provide several technical changes that improve reader domain detection of low-affinity interactions. We show that 1% non-fat milk in 1X PBST as the blocking reagent during incubation improved reader-domain interaction results. Further, coupling this with post-binding high-salt washes and a brief, low-percentage formaldehyde cross-linking step prior to the high-salt washes provided the optimal balance between resolving specific low-affinity interactions and minimizing background or spurious signals. We expect this improved methodology will lead to the elucidation of previously unreported reader-histone interactions that will be important for chromatin function.