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Genetic screens in Drosophila melanogaster have long been used to identify genes found in a variety of developmental, cellular, and behavioral processes. Here we describe the characterization and mapping of a mutation identified in a conditional screen for genetic regulators of cell growth and cell division. Within a Flp/FRT system, mutant G.3.2 results in a reduction of mutant tissue and a rough eye phenotype. We find that G.3.2 maps to the gene cnk , providing further support that cnk is a critical gene in Drosophila eye development. This mutant was characterized, mapped and sequenced by undergraduate students within the Fly-CURE consortium., Competing Interests: The authors declare that there are no conflicts of interest present., (Copyright: © 2024 by the authors.)

Background: Psychological interventions, along with antipsychotic medications, are recommended for adults diagnosed with a psychotic disorder. While initially designed to mitigate positive symptoms, psychological interventions targeting personal recovery were developed and aligned with the recovery framework that many mental health services have adopted. Acceptance and Commitment Therapy (ACT) for psychosis is one such intervention that shows promise when delivered in an individual format. There is preliminary evidence that ACT for psychosis in a group format improves recovery., Objective: This trial aims to evaluate the effectiveness of the "Recovery ACT" group program on personal recovery among adults living with a psychotic disorder., Methods: Our unfunded study is a multiagency, prospective, nonrandomized, waitlist control, single-group trial of the Recovery ACT group program. The program involves 7 weekly group sessions of 90 minutes duration and a 90-minute booster session held 1 month later. We intend to recruit 160 adults living with a psychotic disorder who enroll in a group that is offered as a routine clinical service at participating public mental health services in Melbourne, Victoria, Australia. The 4 assessment time points are 4-6 weeks before the start of the group program, at the start of the group program, at the end of the group program, and at the booster session. There is an optional midgroup assessment and follow-up study. The primary outcome is personal recovery. Secondary outcomes include participants' well-being and psychological flexibility processes. Qualitative data are also collected from participants and facilitators., Results: Recruitment began in September 2019 and is ongoing until 2024, subsequent to a 24-month disruption due to the COVID-19 pandemic. As of the submission of this paper, 93 participants consented to the evaluation, 65 completed T1 measures, and 40 had a complete data set for the proposed analyses., Conclusions: This is the first trial evaluating the effectiveness of the Recovery ACT group program on personal recovery for adults living with a psychotic disorder. Findings will contribute to knowledge about psychosocial interventions for adults living with psychosis. This trial may also serve as an example of a partnership between clinicians and academics that can facilitate the translation of research into practice., Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN12620000223932; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12620000223932., International Registered Report Identifier (irrid): DERR1-10.2196/49849., (©Marilyn L Cugnetto, Eric M J Morris, Siobain F Bonfield, Jesse Gates, Ilona Morrison, Ellie R Newman, Julia D Nicholls, Lisa M Soares, Megan T Antonucci, Jacinta R Clemente, Claire L M Garratt, Eliot Goldstone, David A Pavone, John Farhall. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 18.03.2024.)

Clinical studies frequently report that patients with major mental illness such as schizophrenia and bipolar disorder have co-morbid physical conditions, suggesting that systemic alterations affecting both brain and peripheral tissues might underlie the disorders. Numerous studies have reported elevated levels of anti-Toxoplasma gondii (T. gondii) antibodies in patients with major mental illnesses, but the underlying mechanism was unclear. Using multidisciplinary epidemiological, cell biological, and gene expression profiling approaches, we report here multiple lines of evidence suggesting that a major mental illness-related susceptibility factor, Disrupted in schizophrenia (DISC1), is involved in host immune responses against T. gondii infection. Specifically, our cell biology and gene expression studies have revealed that DISC1 Leu607Phe variation, which changes DISC1 interaction with activating transcription factor 4 (ATF4), modifies gene expression patterns upon T. gondii infection. Our epidemiological data have also shown that DISC1 607 Phe/Phe genotype was associated with higher T. gondii antibody levels in sera. Although further studies are required, our study provides mechanistic insight into one of the few well-replicated serological observations in major mental illness.

The typical dose used to record cryo-electron microscopy images from vitrified biological specimens is so high that radiation-induced structural alterations are bound to occur during data acquisition. Integration of all scattered electrons into one image can lead to significant blurring, particularly if the data are collected from an unsupported thin layer of ice suspended over the holes of a support film. Here, the dose has been fractioned and exposure series have been acquired in order to study beam-induced specimen movements under low dose conditions, prior to bubbling. Gold particles were added to the protein sample as fiducial markers. These were automatically localized and tracked throughout the exposure series and showed correlated motions within small patches, with larger amplitudes of motion vectors at the start of a series compared with the end of each series. A non-rigid scheme was used to register all images within each exposure series, using natural neighbor interpolation with the gold particles as anchor points. The procedure increases the contrast and resolution of the examined macromolecules.

The nucleosome assembly protein (NAP) family represents a key group of histone chaperones that are essential for cell viability. Several x-ray structures of NAP1 dimers are available; however, there are currently no structures of this ubiquitous chaperone in complex with histones. We have characterized NAP1 from Xenopus laevis and reveal that it forms discrete multimers with histones H2A/H2B and H3/H4 at a stoichiometry of one NAP dimer to one histone fold dimer. These complexes have been characterized by size exclusion chromatography, analytical ultracentrifugation, multiangle laser light scattering, and small-angle x-ray scattering to reveal their oligomeric assembly states in solution. By employing single-particle cryo-electron microscopy, we visualized these complexes for the first time and show that they form heterogeneous ring-like structures, potentially acting as large scaffolds for histone assembly and exchange.

Schizophrenia is a complex psychiatric disorder with both genetic and environmental components and is thought to be in part neurodevelopmental in origin. The DISC1 gene has been linked to schizophrenia in two independent Caucasian populations. The DISC1 protein interacts with a variety of proteins including FEZ1, the mammalian homolog of the Caenorhabditis elegans unc-76 protein, which is involved in axonal outgrowth. Variation at the FEZ1 gene has been associated with schizophrenia in a large Japanese cohort. In this study, nine SNP markers at the FEZ1 locus were genotyped in two populations. A North American Caucasian cohort of 212 healthy controls, 178 schizophrenics, 79 bipolar disorder, and 58 with schizoaffective disorder, and an African American cohort of 133 healthy controls, 162 schizophrenics, and 28 with schizoaffective disorder. No association to schizophrenia, bipolar disorder or schizoaffective disorder was found for any of the nine markers typed in these populations at the allelic or the genotypic level. Additionally no association was found in either population between specific haplotypes and any of the psychiatric disorders. Variation at the FEZ1 locus does not play a significant role in the etiology of schizophrenia, bipolar disorder or schizoaffective disorder in North American Caucasian or African American populations.Neuropsychopharmacology (2007) 32, 190-196. doi:10.1038/sj.npp.1301177; published online 16 August 2006.

Exposure to methamphetamine (METH) during the preweanling period produces few, if any, neurotoxic effects (using criteria established in adult rats), yet it has substantial long-term effects on a variety of behavioral measures (e.g., locomotor activity, acoustic startle response, and spatial learning). The purpose of the present study was to examine the long-term changes in dopaminergic functioning brought about by early METH exposure. Rats were injected with METH (10 mg/kg) or saline four times daily on postnatal days (PD) 11-20 and housed undisturbed until PD 90, at which time they were killed and their dorsal striata (i.e., caudate-putamen) were removed and frozen for assay. The ability of early METH exposure to alter protein kinase A (PKA) activity and dopamine (DA) D(2)-like binding sites, as well as DA and DOPAC content, were assessed. Results showed that METH exposure on PD 11-20 caused long-term reductions in all of the dopaminergic markers assayed. METH-induced reductions in DA content and D(2)-like receptors were observed. Some sex differences were apparent, as the METH-induced decreases in PKA activity and DOPAC content were more evident in male rats. In conclusion, preweanling METH exposure caused changes in DA markers that were still detectable at PD 90; however the magnitude of many of these effects (e.g., the reductions in DA and DOPAC levels) was substantially less than typically reported for rats treated with METH in adulthood. The ability of METH to cause long-term reductions in PKA activity may partially account for some of behavioral deficits exhibited by rats exposed to METH prior to weaning., (Copyright 2003 Wiley-Liss, Inc.)

Rationale: The role played by D(1)-like receptors in amphetamine-induced behavioral sensitization has been examined using both the D(1)-like receptor antagonist, SCH 23390, and the D(1A) receptor knockout mouse (i.e. D(1A)-deficient mice). Studies using these two approaches have provided conflicting evidence about the importance of D(1)-like receptors for amphetamine-induced behavioral sensitization., Objective: The purpose of the present study was to determine: (a) whether D(1A)-deficient mice exhibit amphetamine-induced locomotor sensitization after 3 and 17 drug abstinence days, and (b) whether SCH 23390, which binds to both D(1A) and D(1B) receptor subtypes, blocks development of amphetamine sensitization in wild-type and D(1A)-deficient mice., Methods: In the first experiment, adult wild-type and D(1A)-deficient mice were injected with amphetamine (0, 1, 2, 4, or 8 mg/kg, IP) for 7 consecutive days. In the second experiment, wild-type and D(1A)-deficient mice were pretreated with SCH 23390 (0, 0.15, or 0.5 mg/kg, IP) 30 min prior to being injected with amphetamine (0 or 8 mg/kg, IP). After each daily amphetamine injection, mice were placed in activity chambers where distance traveled (i.e. horizontal locomotor activity) was measured for 60 min. On the test days, which occurred after 3 or 17 drug abstinence days, mice were injected with 1 mg/kg amphetamine and locomotion was measured for 120 min., Results: Both wild-type and D(1A)-deficient mice exhibited amphetamine-induced locomotor sensitization. Pretreatment with 0.5 mg/kg SCH 23390 blocked the development of locomotor sensitization in wild-type mice, but did not alter the sensitized responding of D(1A)-deficient mice., Conclusions: It appears that D(1)-like receptors are necessary for the development of amphetamine sensitization in wild-type mice, while neither the D(1A) nor D(1B) receptor subtypes are necessary for the amphetamine-induced locomotor sensitization of D(1A)-deficient mice. A possible explanation for these conflicting results is that D(1A)-deficient mice may have a compensatory mechanism (not involving D(1B) receptors) that allows them to exhibit amphetamine-induced behavioral sensitization in the absence of the D(1A) receptor.

A longitudinal study (employing a multiple separation technique) of chicks' social behavior over the first postnatal month indicated systematic changes in their mode of physical interactions. During the first week or so, intersubject pecking in same-sex pairs was frequent, and was more likely in birds with a home cage advantage (i.e., a prior resident effect). However, there were no sex differences in any of the forms of social pecking (head, body, or feet of the opponent), and all types showed significant decreases over the period of the study. On the contrary, there was a strong effect for sex on rates of aggressive leaping, with males exhibiting more leaps than females. Further, there was a clear increase in leaping over the first weeks of testing, and something of a decline thereafter. These data suggest that in this species the definitive expression of aggressive or dominance behavior may be leaping. Early social pecking (during a period in which this behavior was at its maximum rate) did not predict the subsequent leaping behavior of individuals, but later "leap orders" were highly associated with later "peck orders"., (Copyright © 1981. Published by Elsevier B.V.)