scholarly journals Awake functional MRI detects neural circuit dysfunction in a mouse model of autism

2020 ◽  
Vol 6 (6) ◽  
pp. eaav4520 ◽  
Author(s):  
Tomokazu Tsurugizawa ◽  
Kota Tamada ◽  
Nobukazu Ono ◽  
Sachise Karakawa ◽  
Yuko Kodama ◽  
...  

MRI has potential as a translational approach from rodents to humans. However, given that mouse functional MRI (fMRI) uses anesthetics for suppression of motion, it has been difficult to directly compare the result of fMRI in “unconsciousness” disease model mice with that in “consciousness” patients. We develop awake fMRI to investigate brain function in 15q dup mice, a copy number variation model of autism. Compared to wild-type mice, we find that 15q dup is associated with whole-brain functional hypoconnectivity and diminished fMRI responses to odors of stranger mice. Ex vivo diffusion MRI reveals widespread anomalies in white matter ultrastructure in 15q dup mice, suggesting a putative anatomical substrate for these functional hypoconnectivity. We show that d-cycloserine (DCS) treatment partially normalizes these anormalies in the frontal cortex of 15q dup mice and rescues some social behaviors. Our results demonstrate the utility of awake rodent fMRI and provide a rationale for further investigation of DCS therapy.

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Shinji Sasaki ◽  
Youko Miki ◽  
Takayuki Ibi ◽  
Hiroyuki Wakaguri ◽  
Yuichi Yoshida ◽  
...  

Abstract Background Calf mortality generally occurs in calves prior to weaning, which is a serious problem in cattle breeding. Several causative variants of monogenic Mendelian disorders in calf mortality have been identified, whereas genetic factors affecting the susceptibility of calves to death are not well known. To identify variants associated with calf mortality in Japanese Black cattle, we evaluated calf mortality as a categorical trait with a threshold model and performed a genome-wide copy number variation (CNV) association study on calf mortality. Results We identified a 44-kb deleted-type CNV ranging from 103,317,687 to 103,361,802 bp on chromosome 5, which was associated with the mortality of 1–180-day-old calves. The CNV harbored C1RL, a pseudogene, and an IncRNA localized in the C1R and C1S gene cluster, which is a component of the classical complement activation pathway for immune complexes for infectious pathogens. The average complement activity in CNVR_221 homozygotes at postnatal day 7 was significantly lower than that of wild-type animals and heterozygotes. The frequency of the risk allele in dead calves suffering from diarrhea and pneumonia and in healthy cows was 0.35 and 0.28, respectively (odds ratio = 2.2, P = 0.016), suggesting that CNVR_221 was associated with the mortality of Japanese Black calves suffering from an infectious disease. Conclusions This study identified a deleted-type CNV associated with the mortality of 1–180-day-old calves. The complement activity in CNVR_221 homozygotes was significantly lower than that in heterozygotes and wild type animals. The frequency of the risk allele was higher in dead calves suffering from an infectious disease than in healthy cows. These results suggest that the existence of CNVR_221 in calves could be attributed to a reduction in complement activity, which in turn leads to susceptibility to infections. Thus, the risk allele could serve as a useful marker to reduce the mortality of infected Japanese Black calves.


PLoS Genetics ◽  
2010 ◽  
Vol 6 (9) ◽  
pp. e1001097 ◽  
Author(s):  
Soumya Raychaudhuri ◽  
Joshua M. Korn ◽  
Steven A. McCarroll ◽  
David Altshuler ◽  
Pamela Sklar ◽  
...  

2021 ◽  
Author(s):  
Hua-fu Zhao ◽  
Xiu-ming Zhou ◽  
Jing Wang ◽  
Fan-fan Chen ◽  
Chang-peng Wu ◽  
...  

Abstract Background Epidermal growth factor receptor (EGFR) and lanthionine synthetase C-like 2 (LanCL2) genes locate in the same amplicon, and co-amplification of EGFR and LANCL2 is frequent in glioblastoma. However, the prognostic value of LANCL2 and EGFR co-amplification, and their mRNA and protein expression in glioblastoma remain unclear yet. Methods This study analyzed the prognostic values of the copy number variations (CNVs), mRNA and protein expression of LANCL2 and EGFR in glioblastoma specimens from TCGA database or our tumor banks. Results The amplification of LANCL2 or EGFR, and their co-amplification were frequent in glioblastoma of TCGA database and our tumor banks. CNVs of LANCL2 or EGFR were significantly correlated with IDH1/2 mutation but not MGMT promoter methylation status. LANCL2 or EGFR amplification, and their co-amplification were significantly associated with reduced overall survival (OS) of glioblastoma patients, rather than IDH1/2-wild-type glioblastoma patients. mRNA and protein overexpression of LANCL2 and EGFR was also frequently found in glioblastoma. LANCL2, rather than EGFR, was overexpressed in relapsing glioblastoma, compared with newly diagnosed glioblastoma. However, mRNA or protein expression of EGFR and LANCL2 was not significantly correlated with OS of glioblastoma patients. In addition, the intracellular localization of LanCL2, not EGFR, was associated with the grade of gliomas. Conclusions Taken together, amplification and mRNA overexpression of LANCL2 and EGFR, and their co-amplification and co-expression were frequent in glioblastoma patients. Our findings suggest that CNVs of LANCL2 and EGFR were the independent diagnostic and prognostic biomarkers for histological glioblastoma patients, but not for IDH1/2-wild-type glioblastoma patients.


2018 ◽  
Vol 7 (3) ◽  
pp. 460-465 ◽  
Author(s):  
Annette Mouritsen ◽  
Alexander Siegfried Busch ◽  
Lise Aksglaede ◽  
Ewa Rajpert-De Meyts ◽  
Anders Juul

Objective Only a few genetic loci are known to be associated with male pubertal events. The ability of excreting testosterone (T) and other steroids in the urine depends on sulfation and glucuronidation. One of several essential glucuronidases is encoded by the UGT2B17 gene. In a preliminary report, we found that homozygous deletion of UGT2B17 in boys was associated with lower urinary excretion of T. We hypothesized that boys with a lower glucuronidation capacity may have altered androgen action and excretion affecting pubarche, as this represents a T-dependent event. Design, participants and measures 668 healthy boys (cross-sectional) aged 6.1–21.9 years (COPENHAGEN puberty study conducted from 2005 to 2006) were included. 65 of the boys where followed longitudinally every 6 months. Participants were genotyped for UGT2B17 copy number variation (CNV). Clinical pubertal staging including orchidometry, anthropometry and serum reproductive hormone levels. Results 59 of the 668 boys (8.8%) presented with a homozygous deletion of UGT2B17 (del/del). These boys experienced pubarche at a mean age of 12.73 years (12.00–13.46) vs 12.40 years (12.11–12.68) in boys heterozygous for deletion of UGT2B17 (del/ins) vs 12.06 years (11.79–12.33) in boys with the wild-type genotype (ins/ins) (P = 0.029, corrected for BMI z-score). The effect accounted for 0.34 years delay per allele (95% CI: 0.03–0.64). A comparable trend was observed for onset of testicular enlargement >3 mL but did not reach significance. Conclusion CNV of UGT2B17 is a factor contributing to the timing of male pubarche.


2019 ◽  
Author(s):  
Danny E. Miller

ABSTRACTGenetic stability depends on the maintenance of a variety of chromosome structures and the precise repair of DNA breaks. During meiosis, programmed double-strand breaks (DSBs) made in prophase I are normally repaired as gene conversions or crossovers. Additionally, DSBs are made by the movement of transposable elements (TEs), which must also be resolved. Incorrect repair of these DNA lesions can lead to mutations, copy number variations, translocations, and/or aneuploid gametes. In Drosophila melanogaster, as in most organisms, meiotic DSB repair occurs in the presence of a rapidly evolving multiprotein structure called the synaptonemal complex (SC). Here, whole-genome sequencing is used to investigate the fate of meiotic DSBs in D. melanogaster mutant females lacking functional SC, to assay for de novo CNV formation, and to examine the role of the SC in transposable element movement in flies. The data indicate that, in the absence of SC, copy number variation still occurs but meiotic DSB repair by gene conversion may occur only rarely. Remarkably, an 856-kilobase de novo CNV was observed in two unrelated individuals of different genetic backgrounds and was identical to a CNV recovered in a previous wild-type study, suggesting that recurrent formation of large CNVs occurs in Drosophila. In addition, the rate of novel TE insertion was markedly higher than wild type in one of two SC mutants tested, suggesting that SC proteins may contribute to the regulation of TE movement and insertion in the genome. Overall, this study provides novel insight into the role that the SC plays in genome stability and provides clues as to why SC proteins are among the most rapidly evolving in any organism.


2019 ◽  
Vol 10 (2) ◽  
pp. 525-537 ◽  
Author(s):  
Danny E. Miller

Genetic stability depends on the maintenance of a variety of chromosome structures and the precise repair of DNA breaks. During meiosis, programmed double-strand breaks (DSBs) made in prophase I are normally repaired as gene conversions or crossovers. DSBs can also be made by other mechanisms, such as the movement of transposable elements (TEs), which must also be resolved. Incorrect repair of these DNA lesions can lead to mutations, copy-number changes, translocations, and/or aneuploid gametes. In Drosophila melanogaster, as in most organisms, meiotic DSB repair occurs in the presence of a rapidly evolving multiprotein structure called the synaptonemal complex (SC). Here, whole-genome sequencing is used to investigate the fate of meiotic DSBs in D. melanogaster mutant females lacking functional SC, to assay for de novo CNV formation, and to examine the role of the SC in transposable element movement in flies. The data indicate that, in the absence of SC, copy-number variation still occurs and meiotic DSB repair by gene conversion occurs infrequently. Remarkably, an 856-kilobase de novo CNV was observed in two unrelated individuals of different genetic backgrounds and was identical to a CNV recovered in a previous wild-type study, suggesting that recurrent formation of large CNVs occurs in Drosophila. In addition, the rate of novel TE insertion was markedly higher than wild type in one of two SC mutants tested, suggesting that SC proteins may contribute to the regulation of TE movement and insertion in the genome. Overall, this study provides novel insight into the role that the SC plays in genome stability and provides clues as to why the sequence, but not structure, of SC proteins is rapidly evolving.


2019 ◽  
Vol 41 (4) ◽  
pp. 490-501 ◽  
Author(s):  
Tetsuya Matsuura ◽  
Yoshiaki Maru ◽  
Masashi Izumiya ◽  
Daisuke Hoshi ◽  
Shingo Kato ◽  
...  

Abstract The organoid culture technique has been recently applied to modeling carcinogenesis in several organs. To further explore its potential and gain novel insights into tumorigenesis, we here investigated whether pancreatic ductal adenocarcinoma (PDA) could be generated as subcutaneous tumors in immunocompromised nude mice, by genetic engineering of normal organoids. As expected, acute induction of KrasG12Din vitro occasionally led to development of tiny nodules compatible with early lesions known as pancreatic intraepithelial neoplasia (PanIN). KrasG12D-expressing cells were enriched after inoculation in the subcutis, yet proved rather declined during culture, suggesting that its advantage might depend on surrounding environments. Depletion of growth factors or concurrent Trp53 deletion resulted in its robust enrichment, invariably leading to development of PanIN or large high-grade adenocarcinoma, respectively, consistent with in vivo mouse studies for the same genotype. Progression from PanIN was also recapitulated by subsequent knockdown of common tumor suppressors, whereas the impact of Tgfbr2 deletion was only partially recapitulated, illustrating genotype-dependent requirement of the pancreatic niche for tumorigenesis. Intriguingly, analysis of tumor-derived organoids revealed that KrasG12D-expressing cells with spontaneous deletion of wild-type Kras were positively selected and exhibited an aging-related mutation signature in nude mice, mirroring the pathogenesis of human PDA, and that the sphere-forming potential and orthotopic tumorigenicity in syngenic mice were significantly augmented. These observations highlighted the relevance of the subcutis of nude mice in promoting PDA development despite its ectopic nature. Taken together, pancreatic carcinogenesis could be considerably recapitulated with organoids, which would probably serve as a novel disease model.


2016 ◽  
Vol 115 (3) ◽  
pp. 1263-1272 ◽  
Author(s):  
Min-Yu Sun ◽  
Yukitoshi Izumi ◽  
Ann Benz ◽  
Charles F. Zorumski ◽  
Steven Mennerick

N-methyl-d-aspartate receptors (NMDARs), a major subtype of glutamate receptors mediating excitatory transmission throughout the central nervous system (CNS), play critical roles in governing brain function and cognition. Because NMDAR dysfunction contributes to the etiology of neurological and psychiatric disorders including stroke and schizophrenia, NMDAR modulators are potential drug candidates. Our group recently demonstrated that the major brain cholesterol metabolite, 24 S-hydroxycholesterol (24S-HC), positively modulates NMDARs when exogenously administered. Here, we studied whether endogenous 24S-HC regulates NMDAR activity in hippocampal slices. In CYP46A1−/−(knockout; KO) slices where endogenous 24S-HC is greatly reduced, NMDAR tone, measured as NMDAR-to-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) excitatory postsynaptic current (EPSC) ratio, was reduced. This difference translated into more NMDAR-driven spiking in wild-type (WT) slices compared with KO slices. Application of SGE-301, a 24S-HC analog, had comparable potentiating effects on NMDAR EPSCs in both WT and KO slices, suggesting that endogenous 24S-HC does not saturate its NMDAR modulatory site in ex vivo slices. KO slices did not differ from WT slices in either spontaneous neurotransmission or in neuronal intrinsic excitability, and exhibited LTP indistinguishable from WT slices. However, KO slices exhibited higher resistance to persistent NMDAR-dependent depression of synaptic transmission induced by oxygen-glucose deprivation (OGD), an effect restored by SGE-301. Together, our results suggest that loss of positive NMDAR tone does not elicit compensatory changes in excitability or transmission, but it protects transmission against NMDAR-mediated dysfunction. We expect that manipulating this endogenous NMDAR modulator may offer new treatment strategies for neuropsychiatric dysfunction.


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