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This article, published in the Chemistry of Natural Compounds journal, explores the challenges of extracting polyhydroxyl compounds from medicinal plants and their role in repelling insects. The study focuses on the plant Hylotelephium erythrostictum, which is resilient and adaptable to various weather conditions. The researchers have identified eight polyhydroxyl compounds from this plant, including sarmentosin, sachaloside V, rhodiocyanoside A, lotaustralin, ethyl glucopyranoside, (–)-myrtenyl-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside, maltose, and glycerol. The article provides detailed information about the chemical structures and properties of these compounds. The document also discusses the methods used to collect, identify, extract, and partition the plant, as well as the presence of similar compounds in other species of the Rhodiola genus. The research was supported by funding from the National Natural Science Foundation of China and the Doctor of Natural Science Foundation of Yanbian University. [Extracted from the article]

Here, we report the generation and comprehensive characterization of a knockin mouse model for the hotspot p.Arg87Cys variant of the cytoplasmic FMR1‐interacting protein 2 (CYFIP2) gene, which was recently identified in individuals diagnosed with West syndrome, a developmental and epileptic encephalopathy. The Cyfip2+/R87C mice recapitulated many neurological and neurobehavioral phenotypes of the patients, including spasmlike movements, microcephaly, and impaired social communication. Age‐progressive cytoarchitectural disorganization and gliosis were also identified in the hippocampus of Cyfip2+/R87C mice. Beyond identifying a decrease in CYFIP2 protein levels in the Cyfip2+/R87C brains, we demonstrated that the p.Arg87Cys variant enhances ubiquitination and proteasomal degradation of CYFIP2. ANN NEUROL 2023;93:155–163 [ABSTRACT FROM AUTHOR]

The two members of the cytoplasmic FMR1‐interacting protein family, CYFIP1 and CYFIP2, are evolutionarily conserved multifunctional proteins whose defects are associated with distinct types of brain disorders. Even with high sequence homology between CYFIP1 and CYFIP2, several lines of evidence indicate their different functions in the brain; however, the underlying mechanisms remain largely unknown. Here, we performed reciprocal immunoprecipitation experiments using CYFIP1‐2 × Myc and CYFIP2‐3 × Flag knock‐in mice and found that CYFIP1 and CYFIP2 are not significantly co‐immunoprecipitated with each other in the knock‐in brains compared with negative control wild‐type (WT) brains. Moreover, CYFIP1 and CYFIP2 showed different size distributions by size‐exclusion chromatography of WT mouse brains. Specifically, mass spectrometry‐based analysis of CYFIP1‐2 × Myc knock‐in brains identified 131 proteins in the CYFIP1 interactome. Comparison of the CYFIP1 interactome with the previously identified brain region‐ and age‐matched CYFIP2 interactome, consisting of 140 proteins, revealed only eight common proteins. Investigations using single‐cell RNA‐sequencing databases suggested non‐neuronal cell‐ and neuron‐enriched expression of Cyfip1 and Cyfip2, respectively. At the protein level, CYFIP1 was detected in both neurons and astrocytes, while CYFIP2 was detected only in neurons, suggesting the predominant expression of CYFIP1 in astrocytes. Bioinformatic characterization of the CYFIP1 interactome, and co‐expression analysis of Cyfip1 with astrocytic genes, commonly linked CYFIP1 with focal adhesion proteins. Immunocytochemical analysis and proximity ligation assay suggested partial co‐localization of CYFIP1 and focal adhesion proteins in cultured astrocytes. Together, these results suggest a CYFIP1‐specific association with astrocytic focal adhesion, which may contribute to the different brain functions and dysfunctions of CYFIP1 and CYFIP2. Cover Image for this issue: https://doi.org/10.1111/jnc.15410 [ABSTRACT FROM AUTHOR]

The SH3 and multiple ankyrin repeat domains 3 (Shank3) protein is a core organizer of the macromolecular complex in excitatory postsynapses, and its defects cause numerous synaptopathies, including autism spectrum disorders. Although the function of Shank3 as a postsynaptic scaffold is adequately established, other potential mechanisms through which Shank3 broadly modulates the postsynaptic proteome remain relatively unexplored. In our previous quantitative proteomic analysis, six up-regulated ribosomal proteins were identified in the striatal synaptosome of Shank3-overexpressing transgenic (TG) mice. In the present study, we validated the increased levels of RPLP1 and RPL36A in synaptosome, but not in whole lysate, of the TG striatum. Moreover, protein synthesis and extracellular signaling-regulated kinase (ERK) activity were enhanced in the TG striatal synaptosome. To understand the potential contribution of increased protein synthesis to the proteomic change in the TG striatal synaptosome, we performed RNA-sequencing analyses on both whole synaptosomal and synaptic polysome-enriched fractions. Comparative analyses showed a positive correlation only between the polysome-associated transcriptome and up-regulated proteome in the TG striatal synaptosome. Our findings suggest a novel mechanism through which Shank3 may remodel the postsynaptic proteome by regulating synaptic protein synthesis, whose dysfunction can be implicated in SHANK3-associated synaptopathies. [ABSTRACT FROM AUTHOR]

Variants of the SH3 and multiple ankyrin repeat domains 3 (SHANK3), which encodes postsynaptic scaffolds, are associated with brain disorders. The targeted alleles in a few Shank3 knock-out (KO) lines contain a neomycin resistance (Neo) cassette, which may perturb the normal expression of neighboring genes; however, this has not been investigated in detail. We previously reported an unexpected increase in the mRNA expression of Shank3 exons 1–12 in the brains of Shank3B KO mice generated by replacing Shank3 exons 13–16 with the Neo cassette. In this study, we confirmed that the increased Shank3 mRNA in Shank3B KO brains produced an unusual ∼60 kDa Shank3 isoform (Shank3-N), which did not properly localize to the synaptic compartment. Functionally, Shank3-N overexpression altered the dendritic spine morphology in cultured neurons. Importantly, Shank3-N expression in Shank3B KO mice was not a compensatory response to a reduction of full-length Shank3 because expression was still detected in the brain after normalizing the level of full-length Shank3. Moreover, in another Shank3 KO line (Shank3 gKO) with a similar Shank3 exonal deletion as that in Shank3B KO mice but without a Neo cassette, the mRNA expression levels of Shank3 exons 1–12 were lower than those of wild-type mice and Shank3-N was not detected in the brain. In addition, the expression levels of genes neighboring Shank3 on chromosome 15 were altered in the striatum of Shank3B KO but not Shank3 gKO mice. These results suggest that the Neo cassette has potential off-target effects in Shank3B KO mice. [ABSTRACT FROM AUTHOR]

The cytoplasmic fragile X mental retardation 1 (FMR1)-interacting protein 2 (CYFIP2) gene is associated with epilepsy, intellectual disability (ID), and developmental delay, suggesting its critical role in proper neuronal development and function. CYFIP2 is involved in regulating cellular actin dynamics and also interacts with RNA-binding proteins. However, the adult brain function of CYFIP2 remains unclear because investigations thus far are limited to Cyfip2 heterozygous (Cyfip2+/−) mice owing to the perinatal lethality of Cyfip2 -null mice. Therefore, we generated Cyfip2 conditional knock-out (cKO) mice with reduced CYFIP2 expression in postnatal forebrain excitatory neurons (CaMKIIα-Cre). We found that in the medial prefrontal cortex (mPFC) of adult Cyfip2 cKO mice, CYFIP2 expression was decreased in both layer 2/3 (L2/3) and layer 5 (L5) neurons, unlike the L5-specific CYFIP2 reduction observed in adult Cyfip2+/− mice. Nevertheless, filamentous actin (F-actin) levels were increased only in L5 of Cyfip2 cKO mPFC possibly because of a compensatory increase in CYFIP1, the other member of CYFIP family, in L2/3 neurons. Abnormal dendritic spines on basal, but not on apical, dendrites were consistently observed in L5 neurons of Cyfip2 cKO mPFC. Meanwhile, neuronal excitability and activity were enhanced in both L2/3 and L5 neurons of Cyfip2 cKO mPFC, suggesting that CYFIP2 functions of regulating F-actin and excitability/activity may be mediated through independent mechanisms. Unexpectedly, adult Cyfip2 cKO mice did not display locomotor hyperactivity or reduced anxiety observed in Cyfip2+/− mice. Instead, both exhibited enhanced social dominance accessed by the tube test. Together, these results provide additional insights into the functions of CYFIP2 in the adult brain. [ABSTRACT FROM AUTHOR]

The chemical structures of the compounds were determined from the NMR and MS spectra and by comparison with reported values in the literature. The petroleum ether extract (5.3 g) was subjected to a series of silica gel columns (petroleum ether-ethyl acetate, 30:1 to 2:1) to afford 10 compounds on the basis of TLC analysis and a bioassay-guided fractionation. Compd. 2019; 55: 21. 1:CAS:528:DC%2BC1MXmsFeltbc%3D. 10.1007/s10600-019-02606-w 13 Sielinou VT, Vardamides JC, Ali MS, Ahmed Z, Hameed A, Nkengfack AE. In our continuous effort to explore inhibitory -glucosidase ingredients from this plant, we isolate 10 compounds from the petroleum ether extract of I H. erythromosticum i , which is the first report on compounds from the genus I Hylotelephium i , including diethyl 2-hydroxysuccinate ( B 1 b ), triethyl 2-hydroxypropane-1,2,3-tricarboxylate ( B 2 b ), 5-ethoxy-3-(ethoxycarbonyl)- 3-hydroxy-5-oxopentanoic acid ( B 3 b ), methyl -D-xylopyranoside ( B 4 b ), 4-hydroxy-2-methylphenyl- -D-glucopyranoside ( B 5 b ), 6 I O i -acetylarbutin ( B 6 b ), I cis i -caffeic acid ( B 7 b ), scopoletin ( B 8 b ), 24-propylcholesterol ( B 9 b ), and acacetin-7 I O i - -D-glucopyranoside ( B 10 b ). [Extracted from the article]

Objective: Genetic variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) encoding an actin-regulatory protein are associated with brain disorders, including intellectual disability and epilepsy. However, specific in vivo neuronal defects and potential treatments for CYFIP2-associated brain disorders remain largely unknown. Here, we characterized Cyfip2 heterozygous (Cyfip2+/- ) mice to understand their neurobehavioral phenotypes and the underlying pathological mechanisms. Furthermore, we examined a potential treatment for such phenotypes of the Cyfip2+/- mice and specified a neuronal function mediating its efficacy.Methods: We performed behavioral analyses of Cyfip2+/- mice. We combined molecular, ultrastructural, and in vitro and in vivo electrophysiological analyses of Cyfip2+/- prefrontal neurons. We also selectively reduced CYFIP2 in the prefrontal cortex (PFC) of mice with virus injections.Results: Adult Cyfip2+/- mice exhibited lithium-responsive abnormal behaviors. We found increased filamentous actin, enlarged dendritic spines, and enhanced excitatory synaptic transmission and excitability in the adult Cyfip2+/- PFC that was restricted to layer 5 (L5) neurons. Consistently, adult Cyfip2+/- mice showed increased seizure susceptibility and auditory steady-state responses from the cortical electroencephalographic recordings. Among the identified prefrontal defects, lithium selectively normalized the hyperexcitability of Cyfip2+/- L5 neurons. RNA sequencing revealed reduced expression of potassium channel genes in the adult Cyfip2+/- PFC. Virus-mediated reduction of CYFIP2 in the PFC was sufficient to induce L5 hyperexcitability and lithium-responsive abnormal behavior.Interpretation: These results suggest that L5-specific prefrontal dysfunction, especially hyperexcitability, underlies both the pathophysiology and the lithium-mediated amelioration of neurobehavioral phenotypes in adult Cyfip2+/- mice, which can be implicated in CYFIP2-associated brain disorders. ANN NEUROL 2020;88:526-543. [ABSTRACT FROM AUTHOR]

Background: Infections caused by the carbapenem-resistant Enterobacter cloacae (CREC) bring great challenges to the clinical treatment and pose a serious threat to public health. In this study, we investigated the molecular characteristics of CREC in a tertiary hospital. Materials and Methods: A total of 12 non-duplicate CREC strains isolated during the period of November 2016 to July 2019 were subjected to automated microbial identification and antimicrobial susceptibility testing (AST) using the BD Phoenix-100 identification and antimicrobial susceptibility testing (ID/AST) system. The strains were also subjected to phenotypic screening for the detection of antibiotic resistance genes such as the carbapenemase and other β-lactamase genes, with the use of the polymerase chain reaction assay (PCR). Finally, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE)-based homology analysis were applied. Results: Four types of carbapenemases namely IMP-26, NDM-5, NDM-1, and KPC-2 were identified in 12 CREC strains. IMP-26 was the most prevalent type (6/12 strains, 50 %), followed by NDM-5 (3/12 strains, 25 %). The results of MLST revealed that these 12 strains could be divided into five sequence types (STs) among which ST544 was the dominant type (6/12 strains, 50 %). The PFGE results divided the 12 strains into four clusters. Conclusion: Our study indicated that the epidemics of the IMP-26-producing E. cloacae ST544 strain did occur in the intensive care unit (ICU) of a tertiary hospital. Therefore, early surveillance and strict implementation of control measures are crucial for the prevention of nosocomial infections and transmissions in hospitals. [ABSTRACT FROM AUTHOR]

Introduction: Carbapenem-resistant Enterobacteriaceae (CRE) pose a serious threat to clinical patient management and public health, as they are generally resistant to most antibiotics and cause infections with high mortality rates. Klebsiella pneumoniae ranks second among Enterobacteriaceae species that cause nosocomial infections. In this study, we investigated the epidemic characteristics of carbapenem-resistant K. pneumoniae (CRKP) in the pediatric intensive care unit (PICU) of Yanbian University Hospital. Materials and Methods: A total of 14 non-duplicate CRKP strains, collected from March  2015 to November 2019, were subjected to automated microbial identification and antimicrobial susceptibility tests using the Phoenix-100 ID/AST system. The strains were also subjected to genotypic resistance testing, polymerase chain reaction assays to detect genes encoding carbapenemases and other β-lactamases, multi-locus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE)-based homology analysis. Results: Two carbapenemase genes, KPC-2 and NDM-1 (in eight and six strains, respectively), were detected. MLST enabled the division of the strains into two sequence types, ST11 and ST1224 (containing eight and six strains, respectively). PFGE results classified the 14 strains into clonotypes A–D, of which clonotypes A and B belonged to ST11, while clonotypes C and D belonged to ST1224. Conclusion: Our study reveals that epidemics of the KPC-2-ST11 and NDM-1-ST1224 strains occurred in the PICU of Yanbian University Hospital. Surveillance and strict implementation of prevention and control measures are crucial to prevent the occurrence and rapid spread of nosocomial infections. [ABSTRACT FROM AUTHOR]

Ursolic acid (UA), a plant-derived compound, has many properties beneficial to health. In the present study, we synthesised three series of novel UA derivatives and evaluated their anti-Toxoplasma gondii activity both in vitro and in vivo. Most derivatives exhibited an improved anti-T. gondii activity in vitro when compared with UA (parent compound), whereas compound 3d exhibited the most potent anti-T. gondii activity in vivo. Spiramycin served as the positive control. Additionally, determination of biochemical parameters, including the liver and spleen indexes, indicated compound 3d to effectively reduce hepatotoxicity and significantly enhance anti-oxidative effects, as compared with UA. Furthermore, our molecular docking study indicated compound 3d to possess a strong binding affinity for T. gondii calcium-dependent protein kinase 1 (TgCDPK1). Based on these findings, we conclude that compound 3d, a derivative of UA, could act as a potential inhibitor of TgCDPK1. [ABSTRACT FROM AUTHOR]

Genetic variants of the SH3 and multiple ankyrin repeat domains 3 (SHANK3) gene, which encodes excitatory postsynaptic core scaffolds cause numerous brain disorders. Several lines of Shank3 knock-out (KO) mice with deletions of different Shank3 exons have previously been generated and characterized. The different Shank3 KO mouse lines have both common and line-specific phenotypes. Shank3 isoform diversity is considered a mechanism underlying phenotypic heterogeneity, and compensatory changes through regulation of Shank3 expression may contribute to this heterogeneity. However, whether such compensatory changes occur in Shank3 KO mouse lines has not been investigated in detail. Using previously reported RNA-sequencing analyses, we identified an unexpected increase in Shank3 transcripts in two different Shank3 mutant mouse lines (Shank3B and Shank3ΔC) having partial deletions of Shank3 exons. We validated an increase in Shank3 transcripts in the hippocampus, cortex, and striatum, but not in the cerebellum, of Shank3B heterozygous (HET) and KO mice, using qRT-PCR analyses. In particular, expression of the N-terminal exons 1–12, but not the more C-terminal exons 19–22, was observed to increase in Shank3B mice with deletion of exons 13–16. This suggests a selective compensatory activation of upstream Shank3 promoters. Furthermore, using domain-specific Shank3 antibodies, we confirmed that the increased Shank3 transcripts in Shank3B KO mice produced a small Shank3 isoform that was not detected in wild-type mice. Taken together, our results illustrate another layer of complexity in the regulation of Shank3 expression in the brain, which may also contribute to the phenotypic heterogeneity of different Shank3 KO mouse lines. [ABSTRACT FROM AUTHOR]

The SH3 and multiple ankyrin repeat domains 3 (Shank3) proteins are core organizers of the postsynaptic density in neuronal excitatory synapses, and their defects cause various neurodevelopmental and neuropsychiatric disorders. Mechanistically, Shank3 directly and indirectly interacts with hundreds of synaptic proteins with diverse functions and potentially exerts its regulatory roles in synaptic development and function via these interactors. However, Shank3‐dependent regulation of synaptic abundance has been validated in vivo for only a few Shank3 interactors. Here, using a quantitative proteomic analysis, we identified 136 proteins with altered synaptic abundance in the striatum of Shank3‐overexpressing transgenic (TG) mice. By comparing these proteins with those found in a previous analysis of the postsynaptic density of Shank3 knock‐out (KO) striatum, we identified and confirmed that cylindromatosis‐associated deubiquitinase (Cyld), a deubiquitinase specific for Lys63‐linked polyubiquitin chains, was up‐ and down‐regulated in Shank3 TG and KO striatal synapses, respectively. Consistently, we found that the synaptic levels of Lys63‐linked polyubiquitin chains were down‐ and up‐regulated in the Shank3 TG and KO striata, respectively. Furthermore, by isolating and analyzing the synaptic Cyld complex, we generated a Cyld interactome consisting of 103 proteins, which may include Cyld substrates. Bioinformatic analyses suggested associations of the Cyld interactome with a few brain disorders and synaptic functions. Taken together, these results suggest that Shank3 regulates the synaptic abundance of Cyld in the mouse striatum and, thereby, potentially modulates the Lys63‐linked polyubiquitination of striatal synaptic proteins. [ABSTRACT FROM AUTHOR]

Both deletions and duplications of the SH3 and multiple ankyrin repeat domains 3 (SHANK3) gene, encoding excitatory postsynaptic scaffolds, are causally associated with various brain disorders, suggesting that proper Shank3 dosage is critical for normal brain development and function. In addition to its well-established synaptic functions, recent studies have suggested that Shank3 can also affect gene expression in the nucleus. However, it has not been investigated whether there are a group of genes whose directional expression is regulated in a Shank3 dosage-dependent manner (i.e. showing opposite changes in expression following Shank3 reduction and overexpression). This is an important issue to be examined for better understanding why neuronal development and function are sensitive to Shank3 dosage, and how much transcriptional changes contribute to neuronal phenotypes affected by Shank3 dosage. To examine this, we performed transcriptome analyses on the striatum of Shank3 heterozygous and knock-out mice, which identified three and 17 differentially expressed genes, respectively. We then compared the results to those of our previous striatal transcriptome analysis of Shank3 overexpressing mice and identified 31 candidate genes showing directional expression changes in a Shank3 dosage-dependent manner. However, overall, their Shank3 dosage-dependent fold changes were very subtle (average of absolute log2(fold change) was 0.139). Meanwhile, the gene set enrichment analyses of the striatal transcriptome suggested that Shank3 dosage may affect anchoring junction-related functions. Taken together, these results suggest that Shank3 dosage minimally affects directional gene expression changes in the mouse striatum. [ABSTRACT FROM AUTHOR]

In the mammalian brain, neuronal excitatory synaptic development, function, and plasticity largely rely on dynamic, activity-dependent changes in the macromolecular protein complex called the postsynaptic density (PSD). Activity-dependent Lys48-linked polyubiquitination and subsequent proteasomal degradation of key proteins in the PSD have been reported. However, investigations into the functions and regulatory mechanisms of Lys63-linked polyubiquitination, the second most abundant polyubiquitin form in synapses, have recently begun. Recent studies showed that a Lys63 linkage-specific deubiquitinase (DUB), cylindromatosis-associated DUB (CYLD) localizes to the PSD where its DUB activity is regulated by different kinases. In addition, Lys63-linked polyubiquitination of postsynaptic density 95 (PSD-95), a core scaffolding protein of the PSD, was identified and its functional significance in synaptic plasticity was characterized. In this review, we summarize these recent findings on Lys63-linked polyubiquitination in excitatory postsynapses, and also propose key questions and prospects about this emerging type of posttranslational modification of the PSD proteome. [ABSTRACT FROM AUTHOR]

Background Carbapenem-resistant Enterobacteriaceae (CRE) strains are a major threat to global health. The development of effective control measures requires more detailed phenotypic and genotypic characterization of CRE. Methods CRE isolates were collected from 65 hospitals in 25 provinces across China between January 1, 2012, and December 31, 2016. The isolates were characterized by antimicrobial susceptibility testing and multilocus sequence typing. Genes encoding carbapenemases, mobilized colistin resistance (mcr-1), and β-lactamases were detected by polymerase chain reaction and DNA sequencing. Results A total of 1801 independent CRE isolates (1201 Klebsiella pneumoniae, 282 Escherichia coli, and 179 Enterobacter cloacae) were collected during the study period. Overall, 96.9%, 89.7%, 54.5%, 49.9%, and 40% of CRE strains were susceptible to colistin, tigecycline, amikacin, minocycline, and fosfomycin, respectively. Notably, 1091/1201 (91%) K. pneumoniae, 225/282 (80%) E. coli, and 129/179 (72%) E. cloacae harbored carbapenemase gene. K. pneumoniae carbapenemase (KPC) was predominant in K. pneumoniae (77%), whereas New Delhi metallo-β-lactamase (NDM) was predominant in E. coli (75%) and E. cloacae (53%). The mcr-1 gene was detected in 13 NDM-carrying E. coli isolates (4.6%). Sequence type (ST)11 and ST167 were predominant among the 100 K. pneumoniae and 47 E. coli STs, respectively. KPC-ST11, which accounted for 64% of K. pneumoniae isolates, had higher levels of resistance than non-ST11 strains to aztreonam, fosfomycin, and amikacin (P <.001). The proportions of KPC and NDM enzymes in CRE increased from 2012 to 2016 (54%–59% and 12%–28%, respectively). Conclusions The number of CRE strains harboring carbapenemase is increasing. KPC-ST11 K. pneumoniae, the predominant strain, shows a reduced susceptibility to most available antibiotics. [ABSTRACT FROM AUTHOR]

FIGURE: Expression and stability of wild-type (WT) or mutant CYFIP2 in HEK293T cells or cultured neurons. Second, we examined protein levels of wild-type or mutant CYFIP2 by transfecting the constructs into HEK293T cells or cultured rat cortical neurons (Fig). [Extracted from the article]

Variants of the SH3 and multiple ankyrin repeat domain 3 (SHANK3) gene, encoding excitatory postsynaptic core scaffolding proteins, are causally associated with numerous neurodevelopmental and neuropsychiatric disorders, including autism spectrum disorder (ASD), bipolar disorder, intellectual disability, and schizophrenia (SCZ). Although detailed synaptic changes of various Shank3 mutant mice have been well characterized, broader downstream molecular changes, including direct and indirect changes, remain largely unknown. To address this issue, we performed a transcriptome analysis of the medial prefrontal cortex (mPFC) of adult Shank3 -overexpressing transgenic (TG) mice, using an RNA-sequencing approach. We also re-analyzed previously reported RNA-sequencing results of the striatum of adult Shank3 TG mice and of the prefrontal cortex of juvenile Shank3+/ΔC mice with a 50–70% reduction of Shank3 proteins. We found that several myelin-related genes were significantly downregulated specifically in the mPFC, but not in the striatum or hippocampus, of adult Shank3 TG mice by comparing the differentially expressed genes (DEGs) of the analyses side by side. Moreover, we also found nine common DEGs between the mPFC and striatum of Shank3 TG mice, among which we further characterized ASD- and SCZ-associated G protein-coupled receptor 85 (Gpr85), encoding an orphan Gpr interacting with PSD-95. Unlike the mPFC-specific decrease of myelin-related genes, we found that the mRNA levels of Gpr85 increased in multiple brain regions of adult Shank3 TG mice, whereas the mRNA levels of its family members, Gpr27 and Gpr173 , decreased in the cortex and striatum. Intriguingly, in cultured neurons, the mRNA levels of Gpr27 , Gpr85 , and Gpr173 were modulated by the neuronal activity. Furthermore, exogenously expressed GPR85 was co-localized with PSD-95 and Shank3 in cultured neurons and negatively regulated the number of excitatory synapses, suggesting its potential role in homeostatic regulation of excitatory synapses in Shank3 TG neurons. Finally, we performed a gene set enrichment analysis of the RNA-sequencing results, which suggested that Shank3 could affect the directional expression pattern of numerous ribosome-related genes in a dosage-dependent manner. To sum up, these results reveal previously unidentified brain region-specific and broad molecular changes in Shank3 -overexpressing mice, further elucidating the complexity of the molecular pathophysiology of SHANK3 -associated brain disorders. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Enterobacteriaceae (CRE) are usually resistant to most of antibiotics. Infections caused by such bacteria have a high mortality and pose a serious threat to clinical management and public health. Enterobacter cloacae ranks third among Enterobacteriaceae that cause nosocomial infections. In this study, the molecular characteristics of carbapenem-resistant E. cloacae in China were investigated. From November 2012 to August 2016, 55 non-repetitive strains of carbapenem-resistant E. cloacae were collected from 12 hospitals in 11 Chinese cities. The bacteria were identified with matrix-assisted laser desorption/ionization time of flight mass spectrometry. Antimicrobial susceptibility tests were determined by agar dilution method. Carbapenemase and other β-lactamase genes were detected with PCR and sequencing. Multilocus sequence typing and plasmid conjugation tests were performed. Among the 55 E. cloacae strains, 50 strains were detected to produce 8 types of carbapenemase including NDM-1, NDM-5, IMP-4, IMP-26, IMP-1, KPC-2, and VIM-1. NDM-1 accounted for 68.0% (34/50) among the carbapenemase-producing E. cloacae. A total of 24 sequence types were identified and ST418 was the most common, accounting for 20% (11/55). For further investigation, a pulsed-field gel electrophoresis (PFGE) assay was conducted to identify the PFGE patterns of the strains. These 23 isolates yielded 13 PFGE patterns, which were designated as type A–M. Eight isolates obtained from Shenzhen had the same PFGE pattern (type A) and the remaining 15 isolates belonged to the other 12 PFGE patterns (type B–M). The observation that 8 of the 15 blaNDM−1-positive E. cloacae isolates obtained from Shenzhen with the same PFGE pattern (type A) suggested a transmission outbreak of a common strain. S1-nuclease PFGE and Southern blotting were also conducted to estimate the size of plasmids harbored by blaNDM−1-positive strains. The results showed that the plasmids harboring the blaNDM−1 gene ranged in size from approximately 52–58 kilobases. Our study indicates that carbapenem-resistant E. cloacae strains that produce NDM carbapenemase have strong resistance. Early detection and monitoring of the prevalence of these strains are urgent. [ABSTRACT FROM AUTHOR]

Variants of the cytoplasmic FMR1-interacting protein (CYFIP) gene family, CYFIP1 and CYFIP2, are associated with numerous neurodevelopmental and neuropsychiatric disorders. According to several studies, CYFIP1 regulates the development and function of both pre- and post-synapses in neurons. Furthermore, various studies have evaluated CYFIP2 functions in the postsynaptic compartment, such as regulating dendritic spine morphology; however, no study has evaluated whether and how CYFIP2 affects presynaptic functions. To address this issue, in this study, we have focused on the presynapses of layer 5 neurons of the medial prefrontal cortex (mPFC) in adult Cyfip2 heterozygous (Cyfip2+/−) mice. Electrophysiological analyses revealed an enhancement in the presynaptic short-term plasticity induced by high-frequency stimuli in Cyfip2+/− neurons compared with wild-type neurons. Since presynaptic mitochondria play an important role in buffering presynaptic Ca2+, which is directly associated with the short-term plasticity, we analyzed presynaptic mitochondria using electron microscopic images of the mPFC. Compared with wild-type mice, the number, but not the volume or cristae density, of mitochondria in both presynaptic boutons and axonal processes in the mPFC layer 5 of Cyfip2+/− mice was reduced. Consistent with an identification of mitochondrial proteins in a previously established CYFIP2 interactome, CYFIP2 was detected in a biochemically enriched mitochondrial fraction of the mouse mPFC. Collectively, these results suggest roles for CYFIP2 in regulating presynaptic functions, which may involve presynaptic mitochondrial changes. [ABSTRACT FROM AUTHOR]

Various mutations in the SH3 and multiple ankyrin repeat domains 3 (SHANK3) gene are associated with neurodevelopmental and neuropsychiatric disorders. Thus far, synaptic abnormalities in multiple brain regions, including the hippocampus, prefrontal cortex, striatum, and ventral tegmental area, have been investigated in several lines of Shank3 mutant mice. However, although some reports have shown loss and gain of body weight in Shank3 knock-out and overexpressing transgenic (TG) mice, respectively, the potential functions of Shank3 in the hypothalamus, a brain region critically involved in energy intake and expenditure, are unknown. Hence, we first characterized endogenous Shank3 mRNA and protein expression in the hypothalamus of adult wild-type mice. Thereafter, we performed transcriptome analysis (RNA-sequencing) in the hypothalamus of adult Shank3 TG mice which mildly overexpress Shank3 proteins. By comparing the 174 differentially expressed genes in the hypothalamus with those previously reported in the striatum and medial prefrontal cortex (mPFC) of Shank3 TG mice, we found that 159 were hypothalamus-specific while only 15 were also observed in either the striatum or mPFC. Furthermore, gene set enrichment analysis of the RNA-sequencing analysis revealed that ribosome-related genes were enriched especially in the up-regulated genes of Shank3 TG hypothalamus, which is in contrast to the results of the Shank3 TG striatum and mPFC analyses, where ribosome-related genes were enriched in the down-regulated genes. Beyond revealing endogenous Shank3 mRNA and protein expression in the hypothalamus, our results suggest unique molecular changes in the hypothalamus of Shank3 TG mice compared with those in the striatum and mPFC. [ABSTRACT FROM AUTHOR]

The SH3 and multiple ankyrin repeat domains 3 (SHANK3) gene encodes core scaffolds in neuronal excitatory postsynapses. SHANK3 duplications have been identified in patients with hyperkinetic disorders and early-onset generalized tonic-clonic seizures. Consistently, Shank3 transgenic (TG) mice, which mildly overexpress Shank3 proteins exhibit hyperkinetic behavior and spontaneous seizures. However, the seizure phenotype of Shank3 TG mice has only been investigated in adults of the seizure-sensitive strain FVB/N. Therefore, it remains unknown if spontaneous seizures occur in Shank3 TG mice from the early postnatal stages onward, or even in seizure-resistant strains. Clinically, generalized tonic-clonic seizures are the critical risk factor for epilepsy-associated mortality. However, the potential association between Shank3 overexpression and mortality, at least in mice, has not been investigated in detail. In the present study, we backcrossed Shank3 TG mice in seizure-resistant C57BL/6 J strain and monitored their home-cage activities at 3 weeks of age. Of the 15 Shank3 TG mice monitored, two exhibited spontaneous tonic-clonic seizures, and one died immediately after the seizure event. Based on this observation, we determined the survival rate of the Shank3 TG mice from 3 to 12 weeks of age. We found that approximately 40–45% of the Shank3 TG mice, both males and females, died before reaching 12 weeks of age. Notably, 53% and 70% of the total deaths in male and female Shank3 TG mice, respectively, occurred in the juvenile stages. These results suggest spontaneous seizure and partial lethality of juvenile Shank3 TG mice in seizure-resistant background, further supporting the validity of this model. [ABSTRACT FROM AUTHOR]