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Since its debut in the biomedical research fields in 1981, zebrafish have been used as a vertebrate model organism in more than 40,000 biomedical research studies. Especially useful are zebrafish lines expressing fluorescent proteins in a molecule, intracellular organelle, cell or tissue specific manner because they allow the visualization and tracking of molecules, intracellular organelles, cells or tissues of interest in real time and in vivo. In this review, we summarize representative transgenic fluorescent zebrafish lines that have revolutionized biomedical research on signal transduction, the craniofacial skeletal system, the hematopoietic system, the nervous system, the urogenital system, the digestive system and intracellular organelles.

Genotyping usually entails analysis of the products of polymerase chain reaction (PCR) carried out with genomic DNA (gDNA) as template, and is employed for validation of mutant or transgenic organisms. For genotyping of adult zebrafish, gDNA is often extracted from clipped caudal fin or skin mucus through either alkaline lysis using NaOH or proteinase K (PK) treatment. Further purification of the gDNA using ethanol precipitation was optional. To develop a rapid and noninvasive method that extracts PCR-ready gDNA from adult zebrafish, we combined skin swabbing with PK treatment and demonstrated its efficiency. This method could be applied to a wide range of fish.

Multiple hereditary exostoses (MHE) is a rare autosomal dominant skeletal disorder with a variety of clinical manifestations. We aimed to evaluate the general clinical phenotypic severity of MHE using our own scoring system and analyzed the risk factors associated with severe clinical phenotypes. In this study, 43 patients from 30 families were analyzed. The mutations were identified by direct sequencing of polymerase chain reaction-amplified genomic DNA or by multiplex ligation-dependent probe amplification. According to a new scoring system devised by the authors, the severity of the phenotype was assessed as mild, moderate, or severe based on the deformity of each segment, number of exostoses, leg length discrepancy, and functional limitations. Of 43 patients from 30 families, 39 patients (90.7%) and 24 families (80%) presented with EXT1 or EXT2 mutations. Patients with EXT1 mutations had a significantly worse phenotype than that of patients with EXT2 mutations or without any detectable mutation. The mean clinical score of patients with an EXT1 mutation (5.76; range, 2.0–8.0; SD = 1.60) was higher than that of patients with an EXT2 mutation (4.06; range, 2.0–7.0; SD = 1.47) or of those without any detectable mutation (4.63; range, 3.0–6.0; SD = 1.44; p = 0.005). According to our classification system, more patients with EXT1 mutations had ‘severe disease’ than those with EXT2 mutations. Deformity scores were also higher in patients with EXT1 mutations (p = 0.018). In the multivariate analysis, the deformity score was found to be associated with the ‘severe’ class (p = 0.031). In conclusion, 90.7% of patients with MHE showed EXT mutations. Our scoring system showed reliable results. We suggest that the extent of deformity is an important factor in determining the phenotype of MHE and close monitoring for the development of severe disease is recommended in patients with high deformity scores.

Background IK is a splicing factor that promotes spliceosome activation and contributes to pre-mRNA splicing. Although the molecular mechanism of IK has been previously reported in vitro, the physiological role of IK has not been fully understood in any animal model. Here, we generate an ik knock-out (KO) zebrafish using the CRISPR/Cas9 system to investigate the physiological roles of IK in vivo. Results The ik KO embryos display severe pleiotropic phenotypes, implying an essential role of IK in embryonic development in vertebrates. RNA-seq analysis reveals downregulation of genes involved in skeletal muscle differentiation in ik KO embryos, and there exist genes having improper pre-mRNA splicing among downregulated genes. The ik KO embryos display impaired neuromuscular junction (NMJ) and fast-twitch muscle development. Depletion of ik reduces myod1 expression and upregulates pax7a, preventing normal fast muscle development in a non-cell-autonomous manner. Moreover, when differentiation is induced in IK-depleted C2C12 myoblasts, myoblasts show a reduced ability to form myotubes. However, inhibition of IK does not influence either muscle cell proliferation or apoptosis in zebrafish and C2C12 cells. Conclusion This study provides that the splicing factor IK contributes to normal skeletal muscle development in vivo and myogenic differentiation in vitro.

Alexander disease (AxD) is a neurodegenerative astrogliopathy caused by mutation in the glial fibrillary acidic protein (GFAP) gene. A 42-year-old Korean man presented with temporary gait disturbance and psychiatric regression after a minor head trauma in the absence of bulbar symptoms and signs. Magnetic resonance images of the brain and spinal cord showed significant atrophy of the medulla oblongata and the entire spinal cord as well as contrast-enhanced T2 hypointensity in the basal ganglia. DNA sequencing revealed a novel 33-bp in-frame deletion mutation (p.Glu138_Leu148del) within the 1B rod domain of GFAP, which was predicted to be deleterious by PROVEAN analysis. To test whether the deletion mutant is disease-causing, we performed in vitro GFAP assembly and sedimentation assays, and GFAP aggregation assays in human adrenal carcinoma SW13 (Vim(−)) cells and rat primary astrocytes. All the assays revealed that GFAP p.Glu138_Leu148del is aggregation prone. Based on these findings, we diagnosed the patient with Type II AxD. This is a report that demonstrates the pathogenicity of InDel mutation of GFAP through functional studies. This patient’s atypical presentation as well as the discrepancy between clinical symptoms and radiologic findings may extend the scope of AxD.

IK is a splicing factor that promotes spliceosome activation and contributes to pre-mRNA splicing. Although the molecular mechanism of IK has been previously reported in vitro, the physiological role of IK has not been fully understood in any animal model. Here, we generate an ik knock-out (KO) zebrafish using the CRISPR/Cas9 system to investigate the physiological roles of IK in vivo.The ik KO embryos display severe pleiotropic phenotypes, implying an essential role of IK in embryonic development in vertebrates. RNA-seq analysis reveals downregulation of genes involved in skeletal muscle differentiation in ik KO embryos, and there exist genes having improper pre-mRNA splicing among downregulated genes. The ik KO embryos display impaired neuromuscular junction (NMJ) and fast-twitch muscle development. Depletion of ik reduces myod1 expression and upregulates pax7a, preventing normal fast muscle development in a non-cell-autonomous manner. Moreover, when differentiation is induced in IK-depleted C2C12 myoblasts, myoblasts show a reduced ability to form myotubes. However, inhibition of IK does not influence either muscle cell proliferation or apoptosis in zebrafish and C2C12 cells.This study provides that the splicing factor IK contributes to normal skeletal muscle development in vivo and myogenic differentiation in vitro.

Additional file 7: Figure S3. The Sashimi plots of housekeeping genes in RNA-seq. Sashimi plots of housekeeping genes including (A) actb1, (B) gapdh, and (C) tuba1b from the Integrative Genomics Viewer (IGV) browser in WT (blue plots; lower) and ik KO embryos (red plots; upper). In each plot, minimum splice junction coverage was set to 5 for visual clarity and statistical significance.

Additional file 1: Figure S1. The homology of IK between human and zebrafish. A sequence alignment of IK cytokine proteins from human and zebrafish by NCBI COBALT. The conservation is shown below in red.

Additional file 6: Figure S2. The Sashimi plots of skeletal muscle differentiation genes in RNA-seq. Sashimi plots of skeletal muscle differentiation genes, including (A) cdkn1a, (B) mybpc2a (C) mybpc1, (D) tnnt2e, (E) smyd1a, (F) tnni3k, and (G) acta1a from the Integrative Genomics Viewer (IGV) browser in WT (blue plots; lower) and ik KO embryos (red plots; upper). In each plot, minimum splice junction coverage was set to 5 for visual clarity and statistical significance.

Additional file 9: Figure S4. Sashimi plots of pax7a in RNA-seq. Sashimi plots of pax7a gene from the Integrative Genomics Viewer (IGV) browser in WT (blue plots; lower) and ik KO embryos (red plots; upper). Minimum splice suction coverage was set to 5 for visual clarity and statistical significance.

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody is a myositis-specific marker detected in clinically amyopathic dermatomyositis (DM). DM with anti-MDA5 antibody can be accompanied by rapidly progressive interstitial lung disease (RP-ILD) and other autoimmune disorders. Until now, only one case of neuromyelitis optica (NMO) with anti-MDA5-positive DM has been reported worldwide, in which the patient achieved a favorable outcome with intensive immunotherapy. We report a case of NMO in a patient with anti-MDA5-positive DM complicated by ILD and rheumatoid arthritis. Our patient experienced a fulminant course of NMO, rather than RP-ILD, in the presence of hyperferritinemia, which resulted in profound neurological sequelae despite immunotherapy including rituximab.

Recurrent spontaneous vasospasm of the extracranial internal carotid artery (RSV-eICA) is a rarely recognized cause of ischemic stroke in young adults. However, its pathophysiology remains largely unknown. Through whole-exome sequencing of the ACOX3 gene of two dizygotic Korean twin brothers affected by RSV-eICA, we identified two compound heterozygous missense variants c.235 T > G (p.F79 V) and c.665G > A (p.G222E). In silico analysis indicated that both variants were classified as pathogenic. In vitro ACOX3 enzyme assay indicated practically no enzyme activity in both F79 V and G222E mutants. To determine the effect of the mutants on vasospasm, we used a collagen contraction assay on human aortic smooth muscle cells (HASMC). Carbachol, a cholinergic agonist, induces contraction of HASMC. Knockdown of ACOX3 in HASMC, using siRNA, significantly repressed HASMC contraction triggered by carbachol. The carbachol-induced HASMC contraction was restored by transfection with plasmids encoding siRNA-resistant wild-type ACOX3, but not by transfection with ACOX3 G222E or by co-transfection with ACOX3 F79 V and ACOX3 G222E, indicating that the two ACOX3 mutants suppress carbachol-induced HASMC contraction. We propose that an ACOX3 dysfunction elicits a prolonged loss of the basal aortic myogenic tone. As a result, smooth muscles of the ICA’s intermediate segment, in which the sympathetic innervation is especially rich, becomes hypersensitive to sympathomimetic stimuli (e.g., heavy exercise) leading to a recurrent vasospasm. Therefore, ACOX3 dysfunction would be a causal mechanism of RSV-eICA. For the first time, we report the possible involvement of ACOX3 in maintaining the basal myogenic tone of human arterial smooth muscle.

Ependymal cells (ECs) are multiciliated neuroepithelial cells that line the ventricles of the brain and the central canal of the spinal cord (SC). How ependymal motile cilia are maintained remains largely unexplored. Here we show that zebrafish embryos deficient in Wnt signaling have defective motile cilia, yet harbor intact basal bodies. With respect to maintenance of ependymal motile cilia, plcδ3a is a target gene of Wnt signaling. Lack of Connexin43 (Cx43), especially its channel function, decreases motile cilia and intercellular Ca2+ wave (ICW) propagation. Genetic ablation of cx43 in zebrafish and mice diminished motile cilia. Finally, Cx43 is also expressed in ECs of the human SC. Taken together, our findings indicate that gap junction mediated ICWs play an important role in the maintenance of ependymal motile cilia, and suggest that the enhancement of functional gap junctions by pharmacological or genetic manipulations may be adopted to ameliorate motile ciliopathy., Ependymal cells are supporting cells in the central nervous system. Here the authors elucidate a signalling axis in zebrafish spinal cord ependymal cells that is important for motile cilia assembly and maintenance, demonstrating that it depends on intercellular propagation of calcium ions via connexin 43.

Achieving favorable postoperative outcomes in patients with drug-resistant epilepsy (DRE) requires early referrals for preoperative examinations. The purpose of this study was to investigate the possibility of a user-friendly early DRE prediction model that is easy for nonexperts to utilize.A two-step genotype analysis was performed, by applying 1) whole-exome sequencing (WES) to the initial test set (The multidimensional EPS-DREOur results suggest that EPS-DRE

Background Knowledge of the genetic etiology of epilepsy can provide essential prognostic information and influence decisions regarding treatment and management, leading us into the era of precision medicine. However, the genetic basis underlying epileptogenesis or epilepsy pharmacoresistance is not well-understood, particularly in non-familial epilepsies with heterogeneous phenotypes that last until or start in adulthood. Methods We sought to determine the contribution of known epilepsy-associated genes (EAGs) to the causation of non-familial epilepsies with heterogeneous phenotypes and to the genetic basis underlying epilepsy pharmacoresistance. We performed a multi-center study for whole exome sequencing-based screening of 178 selected EAGs in 243 non-familial adult patients with primarily focal epilepsy (122 drug-resistant and 121 drug-responsive epilepsies). The pathogenicity of each variant was assessed through a customized stringent filtering process and classified according to the American College of Medical Genetics and Genomics guidelines. Results Possible causal genetic variants of epilepsy were uncovered in 13.2% of non-familial patients with primarily focal epilepsy. The diagnostic yield according to the seizure onset age was 25% (2/8) in the neonatal and infantile period, 11.1% (14/126) in childhood and 14.7% (16/109) in adulthood. The higher diagnostic yields were from ion channel-related genes and mTOR pathway-related genes, which does not significantly differ from the results of previous studies on familial or early-onset epilepsies. These potentially pathogenic variants, which were identified in genes that have been mainly associated with early-onset epilepsies with severe phenotypes, were also linked to epilepsies that start in or last until adulthood in this study. This finding suggested the presence of one or more disease-modifying factors that regulate the onset time or severity of epileptogenesis. The target hypothesis of epilepsy pharmacoresistance was not verified in our study. Instead, neurodevelopment-associated epilepsy genes, such as TSC2 or RELN, or structural brain lesions were more strongly associated with epilepsy pharmacoresistance. Conclusions We revealed a fraction of possible causal genetic variants of non-familial epilepsies in which genetic testing is usually overlooked. In this study, we highlight the importance of earlier identification of the genetic etiology of non-familial epilepsies, which leads us to the best treatment options in terms of precision medicine and to future neurobiological research for novel drug development. This should be considered a justification for physicians determining the hidden genetics of non-familial epilepsies that last until or start in adulthood.

Despite recent interest in using zebrafish in human disease studies, sparked by their economics, fecundity, easy handling, and homologies to humans, the electrophysiological tools or methods for zebrafish are still inaccessible. Although zebrafish exhibit more significant larval–adult duality than any other animal, most electrophysiological studies using zebrafish are biased by using larvae these days. The results of larval studies not only differ from those conducted with adults but also are unable to delicately manage electroencephalographic montages due to their small size. Hence, we enabled non-invasive long-term multichannel electroencephalographic recording on adult zebrafish using custom-designed electrodes and perfusion system. First, we exploited demonstration of long-term recording on pentylenetetrazole-induced seizure models, and the results were quantified. Second, we studied skin–electrode impedance, which is crucial to the quality of signals. Then, seizure propagations and gender differences in adult zebrafish were exhibited for the first time. Our results provide a new pathway for future neuroscience research using zebrafish by overcoming the challenges for aquatic organisms such as precision, serviceability, and continuous water seepage.

Nondystrophic myotonias are disorders of Na+ (Nav1.4 or SCN4A) and Cl− (CLCN1) channels in skeletal muscles, and frequently show phenotype heterogeneity. The molecular mechanism underlying their pathophysiology and phenotype heterogeneity remains unclear. As zebrafish models have been recently exploited for studies of the pathophysiology and phenotype heterogeneity of various human genetic diseases, a zebrafish model may be useful for delineating nondystrophic myotonias. Here, we generated transgenic zebrafish expressing a human mutant allele of SCN4A, referred to as Tg(mylpfa:N440K), and needle electromyography revealed increased number of myotonic discharges and positive sharp waves in the muscles of Tg(mylpfa:N440K) than in controls. In addition, forced exercise test at a water temperature of 24 °C showed a decrease in the distance moved, time spent in and number of visits to the zone with stronger swimming resistance. Finally, a forced exercise test at a water temperature of 18 °C exhibited a higher number of dive-bombing periods and drifting-down behavior than in controls. These findings indicate that Tg(mylpfa:N440K) is a good vertebrate model of exercise- and cold-induced human nondystrophic myotonias. This zebrafish model may contribute to provide insight into the pathophysiology of myotonia in sodium channelopathy and could be used to explore a new therapeutic avenue.

This is the simplest cloning strategy, which uses two RE sites in the MCS of a vector. Below are the step by step descriptions of the cut and paste method (Fig. 3.1).

In a modern biology lab, subcloning a gene obtained by RT-PCR into an expression vector and then expressing it in mammalian cells or E. coli are routinely performed. Sometimes, a cloned gene is directly inserted into an expression vector. Other times, it is inserted into a small vector with MCS and then transferred to an expression vector.

When I first started cloning, I feared inserting a DNA fragment into the middle of a gene, such as inserting the EGFP gene into between 96 Leucine (L) and 97 Phenylalanine (F) of Gene A (Fig. 4.1). Insertion here means that EGFP enters into between 96L and 97F without adding any additional nucleotides. When you are extremely lucky (as lucky as winning the lottery), a unique restriction site might fall between 96L and 97F. However, I have never been that lucky. What then can be done? It’s simple. Use PCR. As mentioned before, cloning has become much easier with the advent of PCR.

With a computer, cloning strategy can be efficiently designed, and REs (Restriction endonucleases) can be easily selected for plasmid fingerprinting. Of course, this can be carried out manually, but computer can make your life easier.

Cloning failures keep me awake at night, especially when what appears to be easy-looking cloning did not work out.

What “cloning” means in the laboratory varies depending on the person using it. Some people define “cloning” as animal cloning, while some define it as the discovery of new genes, or some say that cloning is moving particular genes around plasmids (though this is subcloning, to be exact) or mutating genes on plasmids. In this book, what I mean by cloning is moving genes around plasmids, mutating genes, or mining new genes.

If you want to know whether zebrafish have a gene similar to human Gene X, what should you do? One simple approach would be to use UniGene in the NCBI database (National Center for Biotechnology Information; http://www.ncbi.nlm.nih.gov/unigene), which provides lists of orthologs (functionally equivalent genes). This means that if you enter the name of a gene into UniGene, for example Gene X, you get orthologs found in various organisms. Of course, this search is limited to information on Gene X and its orthologs catalogued in UniGene. In recent years, the gene data in UniGene have been accumulating exponentially.

Objectives/Hypothesis The development of a simple, reliable, and cost-effective animal model greatly facilitates disease treatment. We aimed to establish a rapid, simple, and reproducible live zebrafish vestibular schwannoma xenograft model for antitumor drug screening. Methods We optimized each of the following conditions for tumor cell xenografts in zebrafish larvae: larval stage, incubation temperature, and injected cell number. We used NF2-/-mouse Schwann (SC4) cells and generated mCherry fluorescent protein-expressing cells prior to injection into zebrafish larvae. SC4 cells were counted using a fluorescence microscope, suspended in 10% fetal bovine serum, and injected into the center of the yolk sac using a microinjection system. The injected embryos were transferred to E3 medium (for zebrafish embryos), and subsequent tumor formation was observed by fluorescence microscopy over a 5-day period. To validate our model, xenografted embryos were transferred into 6-well plates (5 embryos per well) and treated with everolimus, a known antitumor drug. Results mCherry fluorescent protein-expressing SC4 cells were successfully grafted into the yolk sacs of zebrafish embryos without any immunosuppressant treatment. At 2 days postinjection, the xenografted cells had grown into tumor masses. The optimal speed of tumor formation depended on the larval stage (30 hpf), incubation temperature (31°C), and injected cell number (200 cells). In preliminary tests, everolimus treatment yielded a > 20% reduction in the number of SC4 cells in the yolk. Conclusion Our in vivo model has the potential to greatly facilitate vestibular schwannoma treatment because of its speed, simplicity, reproducibility, and amenability to live imaging. Level of Evidence N/A. Laryngoscope, 2016

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that remodel and degrade the extracellular matrix. Of various MMPs, MMP-2 plays an important role in tumor metastasis. Recently, microRNAs with pro- or anti-metastatic effects were collectively referred to as metastamiRs. We screened 215 human miRNA mimics for modulators of MMP-2 activities in HT-1080 cells, and found that miR-105 and miR-128 promote MMP-2 activities. Bioinformatics analysis predicted that miR-105 and miR-128 both bind to the 3′ untranslated region (UTR) of TIMP-2, an inhibitor of MMP-2 activities. This prediction was verified by reduced luciferase activity in HT-1080 cells co-transfected with miR-105 or miR-128 mimics and plasmids encoding luciferase fused to 3′ UTR of TIMP2. In addition, Western blotting showed that transfection of HT-1080 cells with miR-105 or miR-128 suppressed TIMP-2 levels and enhanced levels of MT1-MMP, an activator of MMP-2 activities. The mechanism by which miR-128 upregulates MT1-MMP was determined to be downregulation of PRKD1, an inhibitor of MT1-MMP, at least in part. Cell invasion assays using Matrigel demonstrated that HT-1080 cells transfected with miR-105 or miR-128 are more invasive as compared to control cells. Taken together, these findings show that miR-105 and miR-128 are metastamir promoting MMP-2 activities via simultaneously downregulating TIMP-2 and upregulating MT1-MMP, and may provide a platform for the development of therapeutics against metastasis.

Dear Editor MDS is a clonal disorder marked by ineffective hematopoiesis, cytopenias, clonal chromosomal abnormalities, and a variable predilection to undergo clonal evolution to AML. Multiple genetic aberrations occur during the clonal evolution of MDS, and in the majority of cases, somatic mutations result from the deletion of all or part of a chromosome [1]. BCR-ABL1 is a hybrid from the ABL1 gene on chromosome 9 and the BCR gene on chromosome 22. The fusion protein encoded from this gene has strong tyrosine kinase activity and is involved in the pathogenesis of several hematologic disorders. BCR-ABL1 genes are categorized into three types, based on differences in the BCR gene's breakpoint, which appear to be related to the disease phenotype. The BCR-ABL1 fusion gene is found in CML and in some cases of acute lymphoblastic leukemia [2]. However, reports on BCR-ABL1-positive MDS cases are extremely rare [3,4,5,6]. Here, we report an unusual case of MDS progressing to AML with an e1a2 BCR-ABL1 fusion transcript and a complex karyotype, including monosomy 7. A 65-yr-old man was admitted for evaluation of persistent pancytopenia with 9% blasts in the peripheral blood. He presented with general weakness and breathlessness. Evaluation of the bone marrow (BM) disclosed hypercellularity with mild erythroid hyperplasia, blasts count of 18%, and remarkable dyshematopoiesis (Fig. 1). Immunophenotype analysis of BM cells using flow cytometry showed that the blasts were positive (>20% of cells) for CD13 (45%), CD33 (97%), CD117 (68%), CD34 (97%), and HLA-DR (43%), and negative for other megakaryocytic and lymphoid markers. Multiplex reverse transcriptase polymerase chain reaction (RT-PCR) evaluation of total RNA isolated from BM cells (HemaVision kit; DNA-Diagnostic, Risskov, Denmark) indicated an e1a2 (p190 BCR-ABL1) rearrangement, confirmed on two independent cDNAs and via direct sequencing (Fig. 2). Quantitative RT-PCR analysis (Real-Q BCR-ABL1 quantification kit; BioSewoom, Seoul, Korea) revealed the BCR-ABL1 to ABL1 transcript ratio to be 0.001339977. The fluorescence in situ hybridization signal for BCR-ABL1 rearrangement was found in one interphase cell out of 296 analyzed cells (Fig. 1D). There was no evidence of other molecular abnormalities such as mutations in JAK2 or calreticulin. Conventional cytogenetic analysis revealed a complex abnormality without the Philadelphia (Ph) chromosome: 44,XY,del(5)(q31),-7,del(12)(p12),-14,-16,+mar [cp20]. The final diagnosis was MDS subtype refractory anemia with excess blasts-2 (RAEB-2). The patient died before undergoing a follow-up BM examination owing to lung cancer, which was found shortly after the MDS diagnosis. Fig. 1 Morphological and molecular cytogenetic analyses of bone marrow cells. A bone-marrow aspirate from the patient showed dyserythropoiesis (A), dysmegakaryopoiesis (B), and dysgranulopoiesis (C). Fluorescence in situ hybridization with a BCR-ABL1 dual-color ... Fig. 2 Detection of p190 BCR-ABL1 fusion transcript by multiplex reverse transcriptase -PCR and direct sequencing. Analysis of RNA samples collected from the patient's bone marrow (A, B). The screening kit produced a single band in the M8 lane (A), and the split-out ... BCR-ABL1-positive de novo MDS is a very rare disease, and when it manifests with excess blasts, as in this case, it may be confused with the accelerated phase of CML. However, several features of this case differentiate it from CML. First, our patient did not have organomegalies, such as splenomegaly, or any related symptoms, which are common in CML. Second, our patient did not display basophilia in the peripheral blood or BM, which is common in CML. Third, BM examination showed severe dyshematopoietic features without findings of myeloproliferative neoplasms. Fourth, monosomy 7 and del(5)(q31) identified using chromosomal analysis are typical aberrations of MDS. It is common that BCR-ABL1-negative MDS changes to BCR-ABL1-positive MDS after disease progression [3,4,5,6]. In the case of BCR-ABL1-positive MDS, most patients show excess blasts on the verge of transformation to AML [6,7,8], which implies that the appearance of BCR-ABL1-positive clones is likely to be closely associated with leukemogenesis and triggers MDS to transform into AML. Jacobsen et al. [9] proposed three possible explanations for the acquisition of the late-appearing Ph chromosome: 1) it may have been present on initial presentation; however, the techniques used were inadequate to detect the BCR rearrangement; 2) it may represent further evidence of multistep pathogenesis; and 3) the presence of the Ph chromosome in some cells may represent the development of a new clone of cells in leukemic relapse. In this case, we presume that the third explanation may be fitting. The BCR-ABL1-positive clone was most likely detected on emergence because the BCR-ABL1 copy number and BCR-ABL1 to ABL1 transcript ratio during quantitative RT-PCR analysis were found to be very low. Moreover, a typical Ph chromosome was not found in 20 metaphase cells by conventional cytogenetic analysis. To the best of our knowledge, this is the first report of de novo MDS RAEB-2 with the cryptic e1a2 subtype of BCR-ABL1 rearrangement and complex chromosomal abnormality in Korea. Currently, there is no established treatment method that is distinguished from the usual MDS treatment. In the future, a more systematic study of this disease is needed with respect to serial biologic monitoring, therapy, and outcome.

In this study, thiol-modified siRNA (SH-siRNA) was delivered by bioreducible polyethylenimine (ssPEI), to enhance physicochemical properties of polyplexes and function of siRNA through disulfide bonding between SH-siRNA and ssPEI. The ssPEI was utilized to deliver Akt1 SH-siRNA for suppression of Akt1 mRNA and blockage of Akt1 protein translation, resulting in reduced cellular proliferation and the induction of apoptosis. Disulfide bondings between the ssPEI and SH-siRNA through thiol groups in both were confirmed by DTT treatment. Complexation between ssPEI and Akt1SH-siRNA was enhanced and reduced surface charge of ssPEI/Akt1SH-siRNA complexes with smaller average particle sizes even at lower N/P ratios was obtained compared with PEI/Akt1siRNA ones. Cellular uptake of ssPEI/Akt1SH-siRNA complexes in CT-26 mouse colon cancer cells was also enhanced. The ssPEI/Akt1SH-siRNA complexes reduced proliferation and increased apoptosis of mouse colon cancer cells in vitro. In an in vivo mouse tumor model, the complexes reduced tumor proliferation and downregulation of Akt1 compared to controls.

Background Alexander disease (AxD) is an astrogliopathy that predominantly affects the white matter of the central nervous system (CNS), and is caused by a mutation in the gene encoding the glial fibrillary acidic protein (GFAP), an intermediate filament primarily expressed in astrocytes and ependymal cells. The main pathologic feature of AxD is the presence of Rosenthal fibers (RFs), homogeneous eosinophilic inclusions found in astrocytes. Because of difficulties in procuring patient’ CNS tissues and the presence of RFs in other pathologic conditions, there is a need to develop an in vivo assay that can determine whether a mutation in the GFAP results in aggregation and is thus disease-causing. Methods We found a GFAP mutation (c.382G > A, p.Asp128Asn) in a 68-year-old man with slowly progressive gait disturbance with tendency to fall. The patient was tentatively diagnosed with AxD based on clinical and radiological findings. To develop a vertebrate model to assess the aggregation tendency of GFAP, we expressed several previously reported mutant GFAPs and p.Asp128Asn GFAP in zebrafish embryos. Results The most common GFAP mutations in AxD, p.Arg79Cys, p.Arg79His, p.Arg239Cys and p.Arg239His, and p.Asp128Asn induced a significantly higher number of GFAP aggregates in zebrafish embryos than wild-type GFAP. Conclusions The p.Asp128Asn GFAP mutation is likely to be a disease-causing mutation. Although it needs to be tested more extensively in larger case series, the zebrafish assay system presented here would help clinicians determine whether GFAP mutations identified in putative AxD patients are disease-causing.

COACH syndrome is an autosomal recessive developmental disorder, a subtype of Joubert syndrome and related disorders, characterized by cerebellar vermis hypoplasia, oligophrenia, ataxia, coloboma, and hepatic fibrosis. Although mutations in TMEM67 (transmembrane protein 67)/MKS3 (Meckel-Gruber syndrome, type 3) were reported to cause COACH syndrome, this causality has not verified by functional studies. In a 20-year-old Korean man, we found cerebellar ataxia, isolated elevation in serum γ-glutamyl transpeptidase (γ-GTP) activity, oligophrenia, the molar tooth sign (MTS) in the brain MR images and congenital hepatic fibrosis (CHF). Two novel compound heterozygous mutations were found in TMEM67 in the patient: i) missense mutation (c.395 G > C and p.Gly132Ala) in exon 3, and ii) deletion in exon 26 (c.2758delT and p.Tyr920ThrfsX40). Western blotting showed that the p.Tyr920ThrfsX40 mutation accelerates turnover of the TMEM67 protein. Although wild-type human TMEM67 RNA rescued phenotypes of zebrafish embryos injected with anti-sense oligonucleotide morpholinos against tmem67, the two human TMEM67 RNAs individually harboring the two mutations did not. Finally, Wnt signaling, but not Hedgehog signaling, was suppressed in tmem67 morphants. To the best of our knowledge, this is the first report verifying the causality between COACH syndrome and TMEM67, which will further our understanding of molecular pathogenesis of the syndrome.

Although additive manufacturing technologies, also known as 3D printing, were first introduced in the 1980s, they have recently gained remarkable popularity owing to decreased costs. 3D printing has already emerged as a viable technology in many industries; in particular, it is a good replacement for microfabrication technology. Microfabrication technology usually requires expensive clean room equipment and skilled engineers; however, 3D printing can reduce both cost and time dramatically. Although 3D printing technology has started to emerge into microfabrication manufacturing and medical applications, it is typically limited to creating mechanical structures such as hip prosthesis or dental implants. There have been increased interests in wearable devices and the critical part of such wearable devices is the sensing part to detect biosignals noninvasively. In this paper, we have built a 3D-printed sensor that can measure electroencephalogram and electrocardiogram from zebrafish. Despite measuring biosignals noninvasively from zebrafish has been known to be difficult due to that it is an underwater creature, we were able to successfully obtain electrophysiological information using the 3D-printed sensor. This 3D printing technique can accelerate the development of simple noninvasive sensors using affordable equipment and provide an economical solution to physiologists who are unfamiliar with complicated microfabrication techniques.

MicroRNAs are increasingly implicated in the modulation of the progression of various cancers. We previously observed that KAI1 C-terminal interacting tetraspanin (KITENIN) is highly expressed in sporadic human colorectal cancer (CRC) tissues and hence the functional KITENIN complex acts to promote progression of CRC. However, it remains unknown that microRNAs target KITENIN and whether KITENIN-targeting microRNAs modulate CRC cell motility and colorectal tumorigenesis. Here, through bioinformatic analyses and functional studies, we showed that miR-124, miR-27a, and miR-30b negatively regulate KITENIN expression and suppress the migration and invasion of several CRC cell lines via modulation of KITENIN expression. Through in vitro and in vivo induction of mature microRNAs using a tetracycline-inducible system, miR-124 was found to effectively inhibit the invasion of CT-26 colon adenocarcinoma cells and tumor growth in a syngeneic mouse xenograft model. Constitutive overexpression of precursor miR-124 in CT-26 cells suppressed in vivo tumorigenicity and resulted in decreased expression of KITENIN as well as that of MYH9 and SOX9, which are targets of miR-124. Thus, our findings identify that KITENIN-targeting miR-124, miR-27a, and miR-30b function as endogenous inhibitors of CRC cell motility and demonstrate that miR-124 among KITENIN-targeting microRNAs plays a suppressor role in colorectal tumorigenesis.

Alexander disease (AxD) is an astrogliopathy that primarily affects the white matter of the central nervous system (CNS). AxD is caused by mutations in a gene encoding GFAP (glial fibrillary acidic protein). The GFAP mutations in AxD have been reported to act in a gain-of-function manner partly because the identified mutations generate practically full-length GFAP. We found a novel nonsense mutation (c.1000 G>T, p.(Glu312Ter); also termed p.(E312*)) within a rod domain of GFAP in a 67-year-old Korean man with a history of memory impairment and leukoencephalopathy. This mutation, GFAP p.(E312*), removes part of the 2B rod domain and the whole tail domain from the GFAP. We characterized GFAP p.(E312*) using western blotting, in vitro assembly and sedimentation assay, and transient transfection of human adrenal cortex carcinoma SW13 (Vim+) cells with plasmids encoding GFAP p.(E312*). The GFAP p.(E312*) protein, either alone or in combination with wild-type GFAP, elicited self-aggregation. In addition, the assembled GFAP p.(E312*) aggregated into paracrystal-like structures, and GFAP p.(E312*) elicited more GFAP aggregation than wild-type GFAP in the human adrenal cortex carcinoma SW13 (Vim+) cells. Our findings are the first report, to the best of our knowledge, on this novel nonsense mutation of GFAP that is associated with AxD and paracrystal formation.

In response to microbial infection, expression of the defensin-like peptide hepcidin (encoded by Hamp) is induced in hepatocytes to decrease iron release from macrophages. To elucidate the mechanism by which Salmonella enterica var. Typhimurium (S. typhimurium), an intramacrophage bacterium, alters host iron metabolism for its own survival, we examined the role of nuclear receptor family members belonging to the NR3B subfamily in mouse hepatocytes. Here, we report that estrogen-related receptor γ (ERRγ, encoded by Esrrg) modulates the intramacrophage proliferation of S. typhimurium by altering host iron homeostasis, and we demonstrate an antimicrobial effect of an ERRγ inverse agonist. Hepatic ERRγ expression was induced by S. typhimurium-stimulated interleukin-6 signaling, resulting in an induction of hepcidin and eventual hypoferremia in mice. Conversely, ablation of ERRγ mRNA expression in liver attenuated the S. typhimurium-mediated induction of hepcidin and normalized the hypoferremia caused by S. typhimurium infection. An inverse agonist of ERRγ ameliorated S. typhimurium-mediated hypoferremia through reduction of ERRγ-mediated hepcidin mRNA expression and exerted a potent antimicrobial effect on the S. typhimurium infection, thereby improving host survival. Taken together, these findings suggest an alternative approach to control multidrug-resistant intracellular bacteria by modulating host iron homeostasis.

Congenital insensitivity to pain with anhidrosis (CIPA), also known as hereditary sensory and autonomic neuropathy type IV, features loss of pain sensation, decreased or absent sweating (anhidrosis), recurrent episodes of unexplained fever, self-mutilating behavior, and variable mental retardation. Mutations in neurotrophic receptor tyrosine kinase 1 (NTRK1) have been reported to be associated with CIPA. We identified four novel NTRK1 mutations in six Korean patients from four unrelated families. Of the four mutations, we demonstrated using a splicing assay that IVS14+3A>T causes aberrant splicing of NTRK1 mRNA, leading to introduction of a premature termination codon. An NTRK1 autophosphorylation assay showed that c.1786G>A (p.Asp596Asn) abolished autophosphorylation of NTRK1. In addition, Western blotting showed that c.704C>G (p.Ser235*) and c.2350_2363del (p.Leu784Serfs*79) blunted NTRK1 expression to undetectable levels. The four novel NTRK1 mutations we report here will expand the repertoire of NTRK1 mutations in CIPA patients, and further our understanding of CIPA pathogenesis.

A 28-year-old woman, who was considered to have Alexander disease (AxD) at 14 months of age, presented with bulbospinocerebellar symptoms from the age of 22 years. Brain MRI showed frontal white matter abnormality with contrast enhancement (figure 1) suggesting type I AxD,1 and atrophy in medulla oblongata and cervical cord as well as pial fluid-attenuated inversion recovery hyperintensities in brainstem (figure 2) suggesting type II.1 GFAP sequencing revealed a heterozygous p.Arg88Cys mutation.