The rockefeller university

Cyclin-dependent kinases (CDKs) regulate a variety of fundamental cellular processes. CDK10 stands out as one of the last orphan CDKs for which no activating cyclin has been identified and no kinase activity revealed. Previous work has shown that CDK10 silencing increases ETS2 (v-ets erythroblastosis virus E26 oncogene homolog 2)-driven activation of the MAPK pathway, which confers tamoxifen resistance to breast cancer cells. The precise mechanisms by which CDK10 modulates ETS2 activity, and more generally the functions of CDK10, remain elusive. Here we demonstrate that CDK10 is a cyclin-dependent kinase by identifying cyclin M as an activating cyclin. Cyclin M, an orphan cyclin, is the product of FAM58A, whose mutations cause STAR syndrome, a human developmental anomaly whose features include toe syndactyly, telecanthus, and anogenital and renal malformations. We show that STAR syndrome-associated cyclin M mutants are unable to interact with CDK10. Cyclin M silencing phenocopies CDK10 silencing in increasing c-Raf and in conferring tamoxifen resistance to breast cancer cells. CDK10/cyclin M phosphorylates ETS2 in vitro, and in cells it positively controls ETS2 degradation by the proteasome. ETS2 protein levels are increased in cells derived from a STAR patient, and this increase is attributable to decreased cyclin M levels. Altogether, our results reveal an additional regulatory mechanism for ETS2, which plays key roles in cancer and development. They also shed light on the molecular mechanisms underlying STAR syndrome.

ObjectiveLithium (Li) is often an effective treatment for mood disorders, especially bipolar disorder (BPD), and can mitigate the effects of stress on the brain by modulating several pathways to facilitate neural plasticity. This review seeks to summarize what is known about the molecular mechanisms underlying Li's actions in the brain in response to stress, particularly how Li is able to facilitate plasticity through regulation of the glutamate system and cytoskeletal components. MethodThe authors conducted an extensive search of the published literature using several search terms, including Li, plasticity, and stress. Relevant articles were retrieved, and their bibliographies consulted to expand the number of articles reviewed. The most relevant articles from both the clinical and preclinical literature were examined in detail. ResultsChronic stress results in morphological and functional remodeling in specific brain regions where structural differences have been associated with mood disorders, such as BPD. Li has been shown to block stress-induced changes and facilitate neural plasticity. The onset of mood disorders may reflect an inability of the brain to properly respond after stress, where changes in certain regions may become locked in' when plasticity is lost. Li can enhance plasticity through several molecular mechanisms, which have been characterized in animal models. Further, the expanding number of clinical imaging studies has provided evidence that these mechanisms may be at work in the human brain. ConclusionThis work supports the hypothesis that Li is able to improve clinical symptoms by facilitating neural plasticity and thereby helps to unlock' the brain from its maladaptive state in patients with mood disorders.

Objectives: To prospectively evaluate QTc changes among methadone maintenance treatment (MMT) patients. Methods: All 512 opiate addicts newly admitted to 2 MMT clinics had been prospectively studied for 4.5 years. Ninety-one patients were excluded because they were admitted from other MMTs, and 26 were excluded because their first electrocardiogram was performed following 28 days in MMT; therefore, 421 were studied. QTc values were again performed either after (A) a steady methadone dose for at least 3 months and negative urine tests for opiates, cocaine, amphetamines, cannabis, benzodiazepine; or after (B) same as for (A) but with positive urine tests for cannabis and/or benzodiazepine. Results: Mean QTc intervals were not related to benzodiazepine or cocaine use on admission. QTc interval was significantly prolonged from the baseline to steady methadone dose (424.5 +/- 23.2 ms and 438.6 +/- 26.6 ms, respectively) but not affected by methadone dose (<100 or >= 100 mg/d) or by the time to achieve a steady methadone dose (between 3 months and >2 years). QTc prolongation was greater among patients whose urine tested positive for benzodiazepine on a steady dose (P = 0.003). No additional prolongation was observed in 49 patients who achieved a steady methadone dose less than 1 year in MMT and had additional follow-up. Two patients who were benzodiazepine abusers died for undefined reasons. Conclusions: There is significant QTc prolongation during early MMT with no apparent clinical significance. A combination of benzodiazepine and methadone should be monitored.

Recent studies link synaptojanin 1 (synj1), the main phosphoinositol (4,5)-biphosphate phosphatase (PI(4,5)P-2-degrading enzyme) in the brain and synapses, to Alzheimer disease. Here we report a novel mechanism by which synj1 reversely regulates cellular clearance of amyloid-beta (A beta). Genetic down-regulation of synj1 reduces both extracellular and intracellular A beta levels in N2a cells stably expressing the Swedish mutant of amyloid precursor protein (APP). Moreover, synj1 haploinsufficiency in an Alzheimer disease transgenic mouse model expressing the Swedish mutant APP and the presenilin-1 mutant Delta E9 reduces amyloid plaque load, as well as A beta(40) and A beta(42) levels in hippocampus of 9-month-old animals. Reduced expression of synj1 attenuates cognitive deficits in these transgenic mice. However, reduction of synj1 does not affect levels of full-length APP and the C-terminal fragment, suggesting that A beta generation by beta- and gamma-secretase cleavage is not affected. Instead, synj1 knockdown increases A beta uptake and cellular degradation through accelerated delivery to lysosomes. These effects are partially dependent upon elevated PI(4,5)P-2 with synj1 down-regulation. In summary, our data suggest a novel mechanism by which reduction of a PI(4,5)P-2-degrading enzyme, synj1, improves amyloid-induced neuropathology and behavior deficits through accelerating cellular A beta clearance.

Background: As microarray technology has become mature and popular, the selection and use of a small number of relevant genes for accurate classification of samples has arisen as a hot topic in the circles of biostatistics and bioinformatics. However, most of the developed algorithms lack the ability to handle multiple classes, arguably a common application. Here, we propose an extension to an existing regularization algorithm, called Threshold Gradient Descent Regularization (TGDR), to specifically tackle multi-class classification of microarray data. When there are several microarray experiments addressing the same/similar objectives, one option is to use a meta-analysis version of TGDR (Meta-TGDR), which considers the classification task as a combination of classifiers with the same structure/model while allowing the parameters to vary across studies. However, the original Meta-TGDR extension did not offer a solution to the prediction on independent samples. Here, we propose an explicit method to estimate the overall coefficients of the biomarkers selected by Meta-TGDR. This extension permits broader applicability and allows a comparison between the predictive performance of Meta-TGDR and TGDR using an independent testing set. Results: Using real-world applications, we demonstrated the proposed multi-TGDR framework works well and the number of selected genes is less than the sum of all individualized binary TGDRs. Additionally, Meta-TGDR and TGDR on the batcheffect adjusted pooled data approximately provided same results. By adding Bagging procedure in each application, the stability and good predictive performance are warranted. Conclusions: Compared with Meta-TGDR, TGDR is less computing time intensive, and requires no samples of all classes in each study. On the adjusted data, it has approximate same predictive performance with Meta-TGDR. Thus, it is highly recommended.

LINE-1s are active human DNA parasites that are agents of genome dynamics in evolution and disease. These streamlined elements require host factors to complete their life cycles, whereas hosts have developed mechanisms to combat retrotransposition's mutagenic effects. As such, endogenous L1 expression levels are extremely low, creating a roadblock for detailed interactomic analyses. Here, we describe a system to express and purify highly active L1 RNP complexes from human suspension cell culture and characterize the copurified proteome, identifying 37 high-confidence candidate interactors. These data sets include known interactors PABPC1 and MOV10 and, with in-cell imaging studies, suggest existence of at least three types of compositionally and functionally distinct L1 RNPs. Among the findings, UPF1, a key nonsense-mediated decay factor, and PCNA, the polymerase-delta-associated sliding DNA clamp, were identified and validated. PCNA interacts with ORF2p via a PIP box motif; mechanistic studies suggest that this occurs during or immediately after target-primed reverse transcription.

Disulfiram is a cocaine addiction pharmacotherapy that inhibits dopamine beta-hydroxylase (D beta H) and reduces norepinephrine production. We examined whether a functional variant of the ADRA1A gene (Cys to Arg at codon 347 in exon 2, Cys347Arg) may enhance treatment response through decreased stimulation of this alpha(1A)-adrenoceptor, since antagonists of this receptor show promise in reducing cocaine use. Sixty-nine cocaine and opioid co-dependent (DSM-IV) subjects were stabilized on methadone for two weeks and subsequently randomized into disulfiram (250 mg/day, N=32) and placebo groups (N=37) for 10 weeks. We genotyped the ADRA1A gene polymorphism (rs1048101) and evaluated its role for increasing cocaine free urines in those subjects treated with disulfiram using repeated measures analysis of variance, corrected for population structure. The 47 patients who carried at least one T allele of rs1048101 (TT or TC genotype) reduced their cocaine positive urines from 84% to 56% on disulfiram (p=0.0001), while the 22 patients with the major allele CC genotype showed no disulfiram effect. This study indicates that a patients ADRA1A genotype could be used to identify a subset of individuals for which disulfiram and, perhaps, other alpha(1)-adrenoceptor blockers may be an effective pharmacotherapy for cocaine dependence. Published by Elsevier B.V.

Searches for anomalous top quark-antiquark production are presented, based on pp collisions at root s = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were collected with the CMS detector at the LHC. The observed t (t) over bar invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements.