mTOR Complex 2 Is Required for the Development of Prostate Cancer Induced by Pten Loss in Mice

mTOR complex 2 (mTORC2) contains the mammalian target of rapamycin (mTOR) kinase and the Rictor regulatory protein and phosphorylates Akt. Whether this function of mTORC2 is critical for cancer progression is unknown. Here, we show that transformed human prostate epithelial cells lacking PTEN require mTORC2 to form tumors when injected into nude mice. Furthermore, we find that Rictor is a haploinsufficient gene and that deleting one copy protects Pten heterozygous mice from prostate cancer. Finally, we show that the development of prostate cancer caused by Pten deletion specifically in prostate epithelium requires mTORC2, but that for normal prostate epithelial cells, mTORC2 activity is nonessential. The selective requirement for mTORC2 in tumor development suggests that mTORC2 inhibitors may be of substantial clinical utility.W. M. Keck FoundationDamon Runyon Cancer Research Foundation (Research Fellowship)Leukemia & Lymphoma Society of America (Career Development Award)Howard Hughes Medical Institute (Investigator)National Institutes of Health (U.S.) (K99 CA1296613-01A1)National Institutes of Health (U.S.) (R01 CA107166)National Institutes of Health (U.S.) (R01 AI04389)National Institutes of Health (U.S.) (R01 CA103866

The Plasma Membrane-Associated GTPase Rin Interacts with the Dopamine Transporter and Is Required for Protein Kinase C-Regulated Dopamine Transporter Trafficking

Dopaminergic signaling and plasticity are essential to numerous CNS functions and pathologies, including movement, cognition, and addiction. The amphetamine- and cocaine-sensitive dopamine (DA) transporter (DAT) tightly controls extracellular DA concentrations and half-life. DAT function and surface expression are not static but are dynamically modulated by membrane trafficking. We recently demonstrated that the DAT C terminus encodes a PKC-sensitive internalization signal that also suppresses basal DAT endocytosis. However, the cellular machinery governing regulated DAT trafficking is not well defined. In work presented here, we identified the Ras-like GTPase, Rin (for Ras-like in neurons) (Rit2), as a protein that interacts with the DAT C-terminal endocytic signal. Yeast two-hybrid, GST pull down and FRET studies establish that DAT and Rin directly interact, and colocalization studies reveal that DAT/Rin associations occur primarily in lipid raft microdomains. Coimmunoprecipitations demonstrate that PKC activation regulates Rin association with DAT. Perturbation of Rin function with GTPase mutants and shRNA-mediated Rin knockdown reveals that Rin is critical for PKC-mediated DAT internalization and functional downregulation. These results establish that Rin is a DAT-interacting protein that is required for PKC-regulated DAT trafficking. Moreover, this work suggests that Rin participates in regulated endocytosis

Association of Glycemic Index and Glycemic Load With Risk of Incident Coronary Heart Disease Among Whites and African Americans With and Without Type 2 Diabetes: The Atherosclerosis Risk in Communities Study

This study examined whether high glycemic index (GI) and glycemic load (GL) diets are associated with increased risk of developing CHD in Whites and African Americans with and without type 2 diabetes

Early life environment and natural history of inflammatory bowel diseases

Background: Early life exposures may modify risk of inflammatory bowel diseases (IBD; Crohn’s disease (CD), ulcerative colitis (UC)). However, the relationship between early life exposures and natural history of IBD has not been previously examined. Methods: This single center study included patients with CD or UC recruited in a prospective IBD registry. Enrolled patients completed a detailed environmental questionnaire that assessed various early life environmental exposures. Our primary outcome was requirement for disease-related surgery in CD and UC. Logistic regression models defined independent effect of early life exposures, adjusting for potential confounders. Results: Our study included 333 CD and 270 UC patients. Just over half were female with a median age at diagnosis of 25 years. One-third of the cohort had history of bowel surgery (31%) and nearly half had used at least one biologic agent (47%). Among those with CD, being breastfed was associated with reduced risk of CD-related surgery (34% vs. 55%), while childhood cigarette smoke exposure was associated with increased risk. On multivariate analysis, history of being breastfed (odds ratio (OR) 0.21, 95% confidence interval [CI] 0.09–0.46) and cigarette smoke exposure as a child (OR 2.17, 95% CI 1.10–4.29) remained independently associated with surgery. None of the early life variables influenced disease phenotype or outcome in UC. Conclusion: A history of being breastfed was associated with a decreased risk while childhood cigarette smoke exposure was associated with an increased risk of surgery in patients with CD. Further investigation to examine biological mechanisms is warranted. Electronic supplementary material The online version of this article (doi:10.1186/s12876-014-0216-8) contains supplementary material, which is available to authorized users

Uncoordinated Loss of Chromatid Cohesion Is a Common Outcome of Extended Metaphase Arrest

Chromosome segregation requires coordinated separation of sister chromatids following biorientation of all chromosomes on the mitotic spindle. Chromatid separation at the metaphase-to-anaphase transition is accomplished by cleavage of the cohesin complex that holds chromatids together. Here we show using live-cell imaging that extending the metaphase bioriented state using five independent perturbations (expression of non-degradable Cyclin B, expression of a Spindly point mutant that prevents spindle checkpoint silencing, depletion of the anaphase inducer Cdc20, treatment with a proteasome inhibitor, or treatment with an inhibitor of the mitotic kinesin CENP-E) leads to eventual scattering of chromosomes on the spindle. This scattering phenotype is characterized by uncoordinated loss of cohesion between some, but not all sister chromatids and subsequent spindle defects that include centriole separation. Cells with scattered chromosomes persist long-term in a mitotic state and eventually die or exit. Partial cohesion loss-associated scattering is observed in both transformed cells and in karyotypically normal human cells, albeit at lower penetrance. Suppressing microtubule dynamics reduces scattering, suggesting that cohesion at centromeres is unable to resist dynamic microtubule-dependent pulling forces on the kinetochores. Consistent with this view, strengthening cohesion by inhibiting the two pathways responsible for its removal significantly inhibits scattering. These results establish that chromosome scattering due to uncoordinated partial loss of chromatid cohesion is a common outcome following extended arrest with bioriented chromosomes in human cells. These findings have important implications for analysis of mitotic phenotypes in human cells and for development of anti-mitotic chemotherapeutic approaches in the treatment of cancer

Development of a real-time quantitative PCR assay for detection of a stable genomic region of BK virus

<p>Abstract</p> <p>Background</p> <p>BK virus infections can have clinically significant consequences in immunocompromised individuals. Detection and monitoring of active BK virus infections in certain situations is recommended and therefore PCR assays for detection of BK virus have been developed. The performance of current BK PCR detection assays is limited by the existence of viral polymorphisms, unknown at the time of assay development, resulting in inconsistent detection of BK virus. The objective of this study was to identify a stable region of the BK viral genome for detection by PCR that would be minimally affected by polymorphisms as more sequence data for BK virus becomes available.</p> <p>Results</p> <p>Employing a combination of techniques, including amino acid and DNA sequence alignment and interspecies analysis, a conserved, stable PCR target region of the BK viral genomic region was identified within the VP2 gene. A real-time quantitative PCR assay was then developed that is specific for BK virus, has an analytical sensitivity of 15 copies/reaction (450 copies/ml) and is highly reproducible (CV ≤ 5.0%).</p> <p>Conclusion</p> <p>Identifying stable PCR target regions when limited DNA sequence data is available may be possible by combining multiple analysis techniques to elucidate potential functional constraints on genomic regions. Applying this approach to the development of a real-time quantitative PCR assay for BK virus resulted in an accurate method with potential clinical applications and advantages over existing BK assays.</p

Structural covariance of the ventral visual stream predicts posttraumatic intrusion and nightmare symptoms: a multivariate data fusion analysis

Visual components of trauma memories are often vividly re-experienced by survivors with deleterious consequences for normal function. Neuroimaging research on trauma has primarily focused on threat-processing circuitry as core to trauma-related dysfunction. Conversely, limited attention has been given to visual circuitry which may be particularly relevant to posttraumatic stress disorder (PTSD). Prior work suggests that the ventral visual stream is directly related to the cognitive and affective disturbances observed in PTSD and may be predictive of later symptom expression. The present study used multimodal magnetic resonance imaging data (n = 278) collected two weeks after trauma exposure from the AURORA study, a longitudinal, multisite investigation of adverse posttraumatic neuropsychiatric sequelae. Indices of gray and white matter were combined using data fusion to identify a structural covariance network (SCN) of the ventral visual stream 2 weeks after trauma. Participant\u27s loadings on the SCN were positively associated with both intrusion symptoms and intensity of nightmares. Further, SCN loadings moderated connectivity between a previously observed amygdala-hippocampal functional covariance network and the inferior temporal gyrus. Follow-up MRI data at 6 months showed an inverse relationship between SCN loadings and negative alterations in cognition in mood. Further, individuals who showed decreased strength of the SCN between 2 weeks and 6 months had generally higher PTSD symptom severity over time. The present findings highlight a role for structural integrity of the ventral visual stream in the development of PTSD. The ventral visual stream may be particularly important for the consolidation or retrieval of trauma memories and may contribute to efficient reactivation of visual components of the trauma memory, thereby exacerbating PTSD symptoms. Potentially chronic engagement of the network may lead to reduced structural integrity which becomes a risk factor for lasting PTSD symptoms

The AURORA Study: A Longitudinal, Multimodal Library of Brain Biology and Function after Traumatic Stress Exposure

Adverse posttraumatic neuropsychiatric sequelae (APNS) are common among civilian trauma survivors and military veterans. These APNS, as traditionally classified, include posttraumatic stress, postconcussion syndrome, depression, and regional or widespread pain. Traditional classifications have come to hamper scientific progress because they artificially fragment APNS into siloed, syndromic diagnoses unmoored to discrete components of brain functioning and studied in isolation. These limitations in classification and ontology slow the discovery of pathophysiologic mechanisms, biobehavioral markers, risk prediction tools, and preventive/treatment interventions. Progress in overcoming these limitations has been challenging because such progress would require studies that both evaluate a broad spectrum of posttraumatic sequelae (to overcome fragmentation) and also perform in-depth biobehavioral evaluation (to index sequelae to domains of brain function). This article summarizes the methods of the Advancing Understanding of RecOvery afteR traumA (AURORA) Study. AURORA conducts a large-scale (n = 5000 target sample) in-depth assessment of APNS development using a state-of-the-art battery of self-report, neurocognitive, physiologic, digital phenotyping, psychophysical, neuroimaging, and genomic assessments, beginning in the early aftermath of trauma and continuing for 1 year. The goals of AURORA are to achieve improved phenotypes, prediction tools, and understanding of molecular mechanisms to inform the future development and testing of preventive and treatment interventions

(Re)Making Public Campus Art: Connecting the University, Publics and the City

Public campus art in the U.K. is predominantly a postwar phenomenon and can be interpreted as artworks situated in university spaces with free access to its audience: any public users — where the multiplicity of such audience defines them as “publics”: communities of interest. Public art’s ontology of “publicness” is complex: what is “public” and who are the “publics”? The local, theme and form of art in “public” space is contested along dualist conceptions of public/private, indoor/outdoor, closed/open, permanent/temporary, decorative/interactive, past/future, space/place, online/offline, and so on and so forth. It may moreover span any material, digital, performative and socially engaged, practice-based work and multimedia beyond more traditional sculptural artworks. This article analyses how public campus art has traditionally related to historic university agendas and campus communities, but has recently provided a platform for far-reaching public engagement beyond the campus, thus reaching new audiences

Lineage-Specific Biology Revealed by a Finished Genome Assembly of the Mouse

A finished clone-based assembly of the mouse genome reveals extensive recent sequence duplication during recent evolution and rodent-specific expansion of certain gene families. Newly assembled duplications contain protein-coding genes that are mostly involved in reproductive function