The Shigella kinase effector OspG modulates host ubiquitin signaling to escape septin-cage entrapment.

Shigella flexneri is a Gram-negative bacterium causing severe bloody dysentery. Its pathogenesis is largely dictated by a plasmid-encoded type III secretion system (T3SS) and its associated effectors. Among these, the effector OspG has been shown to bind to the ubiquitin conjugation machinery (E2~Ub) to activate its kinase activity. However, the cellular targets of OspG remain elusive despite years of extensive efforts. Here we show by unbiased phosphoproteomics that a major target of OspG is CAND1, a regulatory protein controlling the assembly of cullin-RING ubiquitin ligases (CRLs). CAND1 phosphorylation weakens its interaction with cullins, which is expected to impact a large panel of CRL E3s. Indeed, global ubiquitome profiling reveals marked changes in the ubiquitination landscape when OspG is introduced. Notably, OspG promotes ubiquitination of a class of cytoskeletal proteins called septins, thereby inhibiting formation of cage-like structures encircling cytosolic bacteria. Overall, we demonstrate that pathogens have evolved an elaborate strategy to modulate host ubiquitin signaling to evade septin-cage entrapment.

Comprehensive genetic analysis of facioscapulohumeral muscular dystrophy by Nanopore long-read whole-genome sequencing.

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is a high-prevalence autosomal dominant neuromuscular disease characterized by significant clinical and genetic heterogeneity. Genetic diagnosis of FSHD remains a challenge because it cannot be detected by standard sequencing methods and requires a complex diagnosis workflow. METHODS: We developed a comprehensive genetic FSHD detection method based on Oxford Nanopore Technologies (ONT) whole-genome sequencing. Using a case-control design, we applied this procedure to 29 samples and compared the results with those from optical genome mapping (OGM), bisulfite sequencing (BSS), and whole-exome sequencing (WES). RESULTS: Using our ONT-based method, we identified 59 haplotypes (35 4qA and 24 4qB) among the 29 samples (including a mosaic sample), as well as the number of D4Z4 repeat units (RUs). The pathogenetic D4Z4 RU contraction identified by our ONT-based method showed 100% concordance with OGM results. The methylation levels of the most distal D4Z4 RU and the double homeobox 4 gene (DUX4) detected by ONT sequencing are highly consistent with the BSS results and showed excellent diagnostic efficiency. Additionally, our ONT-based method provided an independent methylation profile analysis of two permissive 4qA alleles, reflecting a more accurate scenario than traditional BSS. The ONT-based method detected 17 variations in three FSHD2-related genes from nine samples, showing 100% concordance with WES. CONCLUSIONS: Our ONT-based FSHD detection method is a comprehensive method for identifying pathogenetic D4Z4 RU contractions, methylation level alterations, allele-specific methylation of two 4qA haplotypes, and variations in FSHD2-related genes, which will all greatly improve genetic testing for FSHD.

Effects of intermittent overload doses of oral vitamin D3 on serum 25(OH)D concentrations and the incidence rates of fractures, falls, and mortality in elderly individuals: A systematic review and meta-analysis.

Vitamin D is commonly used to prevent and treat osteoporosis, with studies indicating its potential to reduce fractures, falls, and mortality. However, meta-analyses present inconsistent findings regarding its efficacy, particularly reflecting significant variability in data and outcomes related to various dosing regimens. In this meta-analysis, we assessed the impact of high-dose intermittent oral administration of vitamin D3 on serum 25(OH)D levels, fractures, falls, and mortality among elderly individuals. We included 14 randomized controlled trials (RCTs) and employed Review Manager 5.4 for statistical analysis. Our findings indicate that intermittent monthly administration of vitamin D3 (over 800 IU per day) significantly raised serum 25(OH)D levels at all timepoints after six months, maintaining levels above 75 nmol/L throughout the year. This regimen showed no increase in all-cause mortality, with a risk ratio (95% CI) of 0.95 (0.87-1.04). Likewise, it did not significantly reduce the risks of falls and fractures, with risk ratios of 1.02 (0.98-1.05) and 0.95 (0.87-1.04) respectively. Although one-year intermittent administration significantly increased the concentration of 25(OH)D in serum, further research is needed to determine if this method would increase the incidence of falls. Therefore, it is not recommended at this stage due to the lack of demonstrated safety in additional relevant RCTs. This study had been registered on PROSPERO (CRD42022363229).

ß-asarone inhibits autophagy by activating the PI3K/Akt/mTOR pathway in a rat model of depression in Parkinson's disease.

OBJECTIVE: It is unclear whether ß-asarone has a good antidepressant effect and what is the main mechanism in Depression in Parkinson's disease (DPD) model rats. METHODS: In this study, DPD model rats were screened from 6-OHDA induced rats by sucrose preference test (SPT) and forced swimming test (FST). DPD model rats were divided into eight groups: model group, pramipexole group, ß-asarone low-dose group (ß-asarone 7.5 group), ß-asarone medium-dose group (ß-asarone 15 group), ß-asarone high-dose group (ß-asarone 30 group), 3-MA group, rapamycin group, and PI3K inhibitor group. 28 days after the end of treatment, open field test (OFT), SPT and FST were conducted in rats. The level of α-synuclein (α-syn) in the striatum was determined by enzyme-linked immunosorbent assay (ELISA). The expression of Beclin-1, p62 in the striatum was determined by western blot. The expression of PI3K, p-PI3K, Akt, p-Akt, mTOR, p-mTOR, Beclin-1, and p62 in the hippocampus was determined by western blot. The spine density of neurons in the hippocampus was detected by golgi staining. RESULTS: The results showed that 4-week oral administration of ß-asarone improve the motor and depressive symptoms of DPD model rats, and decrease the content of α-syn in the striatum. ß-asarone inhibited the expression of autophagy in the striatum of DPD model rats. Furthermore, ß-asarone decreased the levels of Beclin-1 protein, increased the expression of p62, p-PI3K, p-AKT, and p-mTOR, and improved the density of neuron dendritic spine in the hippocampus. CONCLUSIONS: We concluded that ß-asarone might improve the behavior of DPD model rats by activating the PI3K/Akt/mTOR pathway, inhibiting autophagy and protecting neuron.

Shigella induces stress granule formation by ADP-riboxanation of the eIF3 complex.

Under stress conditions, translationally stalled mRNA and associated proteins undergo liquid-liquid phase separation and condense into cytoplasmic foci called stress granules (SGs). Many viruses hijack SGs for their pathogenesis; however, whether pathogenic bacteria also exploit this pathway remains unknown. Here, we report that members of the OspC family of Shigella flexneri induce SG formation in infected cells. Mechanistically, the OspC effectors target multiple subunits of the host translation initiation factor 3 complex by ADP-riboxanation. The modification of eIF3 leads to translational arrest and thus the formation of SGs. Furthermore, OspC-mediated SGs are beneficial for S. flexneri replication within infected host cells, and bacterial strains unable to induce SGs are attenuated for virulence in a murine model of infection. Our findings reveal a mechanism by which bacterial pathogens induce SG assembly by inactivating host translational machinery and promote bacterial proliferation in host cells.

Optical Genome Mapping for Chromosomal Aberrations Detection-False-Negative Results and Contributing Factors.

Optical genome mapping (OGM) has been known as an all-in-one technology for chromosomal aberration detection. However, there are also aberrations beyond the detection range of OGM. This study aimed to report the aberrations missed by OGM and analyze the contributing factors. OGM was performed by taking both GRCh37 and GRCh38 as reference genomes. The OGM results were analyzed in blinded fashion and compared to standard assays. Quality control (QC) metrics, sample types, reference genome, effective coverage and classes and locations of aberrations were then analyzed. In total, 154 clinically reported variations from 123 samples were investigated. OGM failed to detect 10 (6.5%, 10/154) aberrations with GRCh37 assembly, including five copy number variations (CNVs), two submicroscopic balanced translocations, two pericentric inversion and one isochromosome (mosaicism). All the samples passed pre-analytical and analytical QC. With GRCh38 assembly, the false-negative rate of OGM fell to 4.5% (7/154). The breakpoints of the CNVs, balanced translocations and inversions undetected by OGM were located in segmental duplication (SD) regions or regions with no DLE-1 label. In conclusion, besides variations with centromeric breakpoints, structural variations (SVs) with breakpoints located in large repetitive sequences may also be missed by OGM. GRCh38 is recommended as the reference genome when OGM is performed. Our results highlight the necessity of fully understanding the detection range and limitation of OGM in clinical practice.

A Novel Splice Site Mutation in the FBN2 Gene in a Chinese Family with Congenital Contractural Arachnodactyly.

Congenital contractural arachnodactyly (CCA) is a rare connective tissue disorder characterized by arachnodactyly, multiple joint contractures, progressive kyphoscoliosis, pectus deformity and abnormal crumpled ears. FBN2 is the only gene currently known to be associated with CCA. In this study, we report on a prenatal case presented with skeletal, cardiac and spinal malformations. And his father had elongated limbs, contractures of the proximal interphalangeal joints, high myopia and scoliosis. We conducted whole exome sequencing (WES) on the fetus-parental trio and a heterozygous variant (hg19 chr5:127,673,685, c.3598 + 4A > G, NM_001999.4) in intron 27 of the FBN2 gene was successfully identified, inherited from the father. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to evaluate the potential splicing effect of this variant, which confirmed that the variant caused a deletion of exon 27 (126 bp) by disrupting the splice-donor site and destroyed the 17th calcium-binding epidermal growth factor-like (cbEGF) domain. Our research not only finds the etiology of the disease in affected individuals and expands the mutation spectrum of FBN2 gene, but also provides genetic counseling and fertility guidance for this family.

Comparative Biomechanical Analysis of Anterior Process Locking Plate Alone versus Combined with Percutaneous Cannulated Screw Fixation for Sanders Type II Calcaneal Fractures: A Finite Element Study.

BACKGROUND Calcaneal fractures are the most common tarsal bone fractures, and account for 75% of intra-articular fractures. The purpose of this study was to compare the biomechanical stability of the anterior process locking plate combined with the percutaneous cannulated screw fixation (screw group) versus the anterior process locking plate fixation alone (plate group) for the treatment of Sanders type II calcaneal fractures using finite element analysis to provide a theoretical basis for clinical work. MATERIAL AND METHODS We established a 3D model of Sanders type II calcaneal fracture; assigned material properties to the internal fixation systems; applied loads; set up analysis criteria; analyzed the displacement of the fracture, relative displacement, stress state of bone tissue, and internal fixation; and compared mechanical stability. RESULTS For Sanders type II A, II B, and II C calcaneal fractures, the degree of displacement and relative displacement of the fracture in the screw group was less than that of the plate group. For all subtypes of Sanders type II calcaneal fractures, the screw group had better mechanical stability than the plate group. CONCLUSIONS Both fixation methods (screw and plate group) were within a reasonable range for restoring the levelling effect of the joint surface and maintaining the strength of fixation, and both had good mechanical stability. Finite element analysis is a relatively reliable method, and biomechanics and clinical studies must further verify the experimental results.

miR-29a-3p Regulates Autophagy by Targeting Akt3-Mediated mTOR in SiO2-Induced Lung Fibrosis.

Silicosis is a refractory pneumoconiosis of unknown etiology that is characterized by diffuse lung fibrosis, and microRNA (miRNA) dysregulation is connected to silicosis. Emerging evidence suggests that miRNAs modulate pulmonary fibrosis through autophagy; however, its underlying molecular mechanism remains unclear. In agreement with miRNA microarray analysis, the qRT-PCR results showed that miR-29a-3p was significantly decreased in the pulmonary fibrosis model both in vitro and in vivo. Increased autophagosome was observed via transmission electron microscopy in lung epithelial cell models and lung tissue of silicosis mice. The expression of autophagy-related proteins LC3α/ß and Beclin1 were upregulated. The results from using 3-methyladenine, an autophagy inhibitor, or rapamycin, an autophagy inducer, together with TGF-ß1, indicated that autophagy attenuates fibrosis by protecting lung epithelial cells. In TGF-ß1-treated TC-1 cells, transfection with miR-29a-3p mimics activated protective autophagy and reduced alpha-smooth muscle actin and collagen I expression. miRNA TargetScan predicted, and dual-luciferase reporter experiments identified Akt3 as a direct target of miR-29a-3p. Furthermore, Akt3 expression was significantly elevated in the silicosis mouse model and TGF-ß1-treated TC-1 cells. The mammalian target of rapamycin (mTOR) is a central regulator of the autophagy process. Silencing Akt3 inhibited the transduction of the mTOR signaling pathway and activated autophagy in TGF-ß1-treated TC-1 cells. These results show that miR-29a-3p overexpression can partially reverse the fibrotic effects by activating autophagy of the pulmonary epithelial cells regulated by the Akt3/mTOR pathway. Therefore, targeting miR-29a-3p may provide a new therapeutic strategy for silica-induced pulmonary fibrosis.

11q13.3q13.4 deletion plus 9q21.13q21.33 duplication in an affected girl arising from a familial four-way balanced chromosomal translocation.

BACKGROUND: We describe a 13-year-old girl with a 11q13.3q13.4 deletion encompassing the SHANK2 gene and a 9q21.13q21.33 duplication. She presented with pre- and postnatal growth retardation, global developmental delay, severe language delay, cardiac abnormalities, and dysmorphisms. Her maternal family members all had histories of reproductive problems. METHODS: Maternal family members with histories of reproductive problems were studied using G-banded karyotyping and optical genome mapping (OGM). Long-range PCR (LR-PCR) and Sanger sequencing were used to confirm the precise break point sequences obtained by OGM. RESULTS: G-banded karyotyping characterized the cytogenetic results as 46,XX,der(9)?del(9)(q21q22)t(9;14)(q22;q24),der(11)ins(11;?9)(q13;?q21q22),der(14)t(9;14). Using OGM, we determined that asymptomatic female family members with reproductive problems were carriers of a four-way balanced chromosome translocation. Their karyotype results were further refined as 46,XX,der(9)del(9)(q21.13q21.33)t(9;14)(q21.33;q22.31),der(11)del(11)(q13.3q13.4)ins(11;9)(q13.3;q21.33q21.13),der(14)t(9:14)ins(14;11)(q23.1;q13.4q13.3). Thus, we confirmed that the affected girl inherited the maternally derived chromosome 11. Furthermore, using LR-PCR, we showed that three disease-related genes (TMC1, NTRK2, and KIAA0586) were disrupted by the breakpoints. CONCLUSIONS: Our case highlights the importance of timely parental origin testing for patients with rare copy number variations, as well as the accurate characterization of balanced chromosomal rearrangements in families with reproductive problems. In addition, our case demonstrates that OGM is a useful clinical application for analyzing complex structural variations within the human genome.

Evaluating the performance of four assays for carrier screening of spinal muscular atrophy.

BACKGROUND AND AIMS: Spinal muscular atrophy (SMA) is an autosomal recessive inherited neuromuscular condition caused by biallelic mutations in the survival of motor neuron 1 (SMN1) gene. A homozygous deletion of the SMN1 gene accounts for approximately 95-98% of SMA patients. A highly homologous gene survival motor neuron 2 (SMN2) can partially compensate for SMN1 deletion, and its copy number is associated with disease severity. Population-based carrier screening by simultaneous quantification of SMN1 and SMN2 copy numbers is the best method to prevent SMA. MATERIALS AND METHODS: In this study, a total of 516 samples were re-tested for the SMN1 copy number by using quantitative polymerase chain reaction (qPCR), multiplex ligation probe amplification (MLPA), droplet digital PCR (ddPCR), high-resolution melting (HRM) analysis, and PCR-based capillary electrophoresis (PCR/CE) simultaneously. Then, the performance of these methods was compared by using MLPA results as the reference. RESULTS: The results of qPCR, ddPCR, HRM, and PCR/CE in detecting heterozygous deletion of SMN1 exon 7 and the results of ddPCR, HRM, and PCR/CE in detecting ≥2 copies of SMN1 exon7 are totally consistent with those of MLPA. The sensitivity and specificity of qPCR for detection of 2 copies of SMN1 exon 7 were 99.7% and 98.8%, respectively. The sensitivity and specificity of qPCR for detection of >2 copies of SMN1 exon 7 were 96.3% and 99.8%, respectively. Compared with the MLPA results, the sensitivity and specificity of qPCR and HRM for detection of heterozygous deletion of SMN1 exon 8 were 100% and 100%, respectively. They were 99.4% and 100%, respectively for detection of 2 copies, and 100% and 100%, respectively for detection of >2 copies. The results of PCR/CE in detecting SMN1 exon 8 were consistent with those of MLPA. CONCLUSION: All these four methods show excellent performance in detecting heterozygous deletion of SMN1 exon 7. All PCR/CE results are totally concordant with those of MLPA. As the most cost-effective method, qPCR also shows high sensitivity and specificity in detecting SMN1. Taken together, our study provides useful information to select appropriate methods for SMA carrier screening.

METTL14 is decreased and regulates m6 A modification of α-synuclein in Parkinson's disease.

N6-methyladenosine (m6A), an emerging modification of messenger RNA, has been implicated in many biological processes. However, its role in Parkinson's disease (PD) remains largely unknown. Here, we investigated the role of m6A modification and its underlying mechanism in PD. First, 86 individuals with PD and 86 healthy controls were recruited from a pilot multicenter cohort. Levels of m6A and its modulators in peripheral blood mononuclear cells of patients with PD and controls were measured using an m6A RNA methylation quantification kit and quantitative real-time PCR. The underlying mechanism of m6A modification in PD was investigated in vitro through RNA immunoprecipitation assay, RNA stability assay, gene silencing or overexpression, western blot, and confocal immunoassay. The results show that mRNA levels of m6A, METTL3, METTL14, and YTHDF2 in patients with PD were significantly lower than in healthy controls, and METTL14 was the main factor involved in abnormal m6A modification. Area under the curve (AUC) analysis suggests METTL14 may provide excellent diagnostic capability for PD, especially when combined with plasma α-synuclein (α-syn). Spearman correlation analysis identified that METTL14 was moderately negatively correlated with plasma α-syn and the motor function of PD. Mechanistic experiments demonstrated that Mettl14 targets and regulates the expression of the α-syn gene using its methylation function. Overexpression of Mettl14 dramatically increased m6 A modification of α-syn mRNA and weakened its stability. Further results suggest that α-syn mRNA was modified by Mettl14 binding of an m6 A motif in the coding region of α-syn mRNA, while the reading protein Ythdf2 was involved in recognizing m6 A-modified α-syn mRNA. Taken together, our results reveal the potential of METTL14 as a novel diagnostic biomarker for PD and identify modification of pathogenic α-syn protein by METTL14 via an m6 A-YTHDF2-dependent mechanism.

Optical genome mapping for detection of chromosomal aberrations in prenatal diagnosis.

INTRODUCTION: Chromosomal aberrations are the most important etiological factors for birth defects. Optical genome mapping is a novel cytogenetic tool for detecting a broad range of chromosomal aberrations in a single assay, but relevant clinical feasibility studies of optical genome mapping in prenatal diagnosis are limited. MATERIAL AND METHODS: We retrospectively performed optical genome mapping analysis of amniotic fluid samples from 34 fetuses with various clinical indications and chromosomal aberrations detected through standard-of-care technologies, including karyotyping, fluorescence in situ hybridization, and/or chromosomal microarray analysis. RESULTS: In total, we analyzed 46 chromosomal aberrations from 34 amniotic fluid samples, including 5 aneuploidies, 10 large copy number variations, 27 microdeletions/microduplications, 2 translocations, 1 isochromosome, and 1 region of homozygosity. Overall, 45 chromosomal aberrations could be confirmed by our customized analysis strategy. Optical genome mapping reached 97.8% concordant clinical diagnosis with standard-of-care methods for all chromosomal aberrations in a blinded fashion. Compared with the widely used chromosomal microarray analysis, optical genome mapping additionally determined the relative orientation and position of repetitive segments for seven cases with duplications or triplications. The additional information provided by optical genome mapping will be conducive to characterizing complex chromosomal rearrangements and allowing us to propose mechanisms to explain rearrangements and predict the genetic recurrence risk. CONCLUSIONS: Our study highlights that optical genome mapping can provide comprehensive and accurate information on chromosomal aberrations in a single test, suggesting that optical genome mapping has the potential to become a promising cytogenetic tool for prenatal diagnosis.

Circ_0005615 restrains the progression of multiple myeloma through modulating miR-331-3p and IGF1R regulatory cascade.

BACKGROUND: Circular RNAs are implicated in modulating the progression of various malignant tumors. However, the function and underlying mechanisms of circ_0005615 in multiple myeloma (MM) remain unclear. METHODS: The expression levels of circ_0005615, miR-331-3p and IGF1R were tested by quantitative real-time polymerase chain reaction or western blot assay. Cell counting kit-8 and 5-ethynyl-2'-deoxyuridine (EdU) assay were performed for cell proliferation detection. Cell apoptosis and cell cycle were measured by flow cytometry. The protein expressions of Bax and Bcl-2 were detected by western blot assay. Glucose consumption, lactate production and ATP/ADP ratios were estimated to disclose cell glycolysis. The interaction relationship among miR-331-3p and circ_0005615 or IGF1R was proved by dual-luciferase reporter assay. RESULTS: The abundance of circ_0005615 and IGF1R was increased in MM patients and cells, while the expression of miR-331-3p was decreased. Circ_0005615 inhibition retarded the proliferation and cell cycle progression, while reinforced the apoptosis of MM cells. Molecularly, circ_0005615 could sponge miR-331-3p, and the repressive trends of circ_0005615 deficiency on MM progression could be alleviated by anti-miR-331-3p introduction. Additionally, IGF1R was validated to be targeted by miR-331-3p, and IGF1R overexpression mitigated the suppressive function of miR-331-3p on MM development. Furthermore, IGF1R was mediated by circ_0005615/miR-331-3p axis in MM cells. CONCLUSION: Circ_0005615 downregulation blocked MM development by targeting miR-331-3p/IGF1R axis.

Whole genome sequencing vs chromosomal microarray analysis in prenatal diagnosis.

BACKGROUND: Emerging studies suggest that whole genome sequencing provides additional diagnostic yield of genomic variants when compared with chromosomal microarray analysis in the etiologic diagnosis of infants and children with suspected genetic diseases. However, the application and evaluation of whole genome sequencing in prenatal diagnosis remain limited. OBJECTIVE: This study aimed to evaluate the accuracy, efficacy, and incremental yield of whole genome sequencing in comparison with chromosomal microarray analysis for routine prenatal diagnosis. STUDY DESIGN: In this prospective study, a total of 185 unselected singleton fetuses with ultrasound-detected structural anomalies were enrolled. In parallel, each sample was subjected to whole genome sequencing and chromosomal microarray analysis. Aneuploidies and copy number variations were detected and analyzed in a blinded fashion. Single nucleotide variations and insertions and deletions were confirmed by Sanger sequencing, and trinucleotide repeats expansion variants were verified using polymerase chain reaction plus fragment-length analysis. RESULTS: Overall, genetic diagnoses using whole genome sequencing were obtained for 28 (15.1%) cases. Whole genome sequencing not only detected all these aneuploidies and copy number variations in the 20 (10.8%) diagnosed cases identified by chromosomal microarray analysis, but also detected 1 case with an exonic deletion of COL4A2 and 7 (3.8%) cases with single nucleotide variations or insertions and deletions. In addition, 3 incidental findings were detected including an expansion of the trinucleotide repeat in ATXN3, a splice-sites variant in ATRX, and an ANXA11 missense mutation in a case of trisomy 21. CONCLUSION: Compared with chromosomal microarray analysis, whole genome sequencing increased the additional detection rate by 5.9% (11/185). Using whole genome sequencing, we detected not only aneuploidies and copy number variations, but also single nucleotide variations and insertions and deletions, trinucleotide repeat expansions, and exonic copy number variations with high accuracy in an acceptable turnaround time (3-4 weeks). Our results suggest that whole genome sequencing has the potential to be a new promising prenatal diagnostic test for fetal structural anomalies.

The emerging role of circular RNAs in Parkinson's disease.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and the most common movement disorder. It involves a gradual loss of dopaminergic neurons in the substantia nigra. Although many studies have been conducted, the underlying molecular pathways of PD remain largely unknown. Circular RNAs (circRNAs), a novel class of non-coding RNAs with a covalently closed loop structure, are common in the brain. They are stable, conserved molecules that are widely expressed in eukaryotes in tissue-, cell-, and development-specific patterns. Many circRNAs have recently been identified in nervous system diseases, and some circRNA expression profiles have been linked to PD. Given that recent research has indicated the essential roles of various circRNAs in the development and progression of neurodegenerative diseases, the identification of individual circRNAs may be a promising strategy for finding new treatment targets for PD. Moreover, the search for circRNAs with high specificity and sensitivity will open up new avenues for the early diagnosis and treatment of PD. Herein, we address the biogenesis, properties, and roles of circRNAs and review their potential utility as biomarkers and therapeutic targets in PD.

Both prokaryotes and eukaryotes produce an immune response against plasmids with 5'-GTTTGTT-3'.

In the evolutionary "arms race" from prokaryotes to eukaryotes, some memories of foreign DNA have been conserved for defensive purposes. Shortly after invasion by the plasmid, pEGFP-N1, the conserved the defense gene, isg15, was activated in the zebrafish zygote and in mammalian cells. Based on the sequence similarity, we found three virus-derived sequences in pEGFP-N1 which share the 5'-GTTTGTT-3' core sequence, an epigenetic factor leading to increased expression of isg15. Mutation of the core sequence greatly reduces the degradation rate of the plasmid in E. coli cells or zebrafish embryos. We conclude that a conserved defense response, common to both eukaryotic and prokaryotic cells, allows identification and degradation of plasmids containing 5'-GTTTGTT-3'.

The Potential Circular RNAs Biomarker Panel and Regulatory Networks of Parkinson's Disease.

Parkinson's disease (PD) is a progressive neurodegenerative disease. It has been reported that circular RNAs (circRNAs) play important roles in several neurological diseases. However, the role and regulatory networks of circRNAs in PD are still largely unclear. In this study, we first compared the global expression level of circRNAs from patients with PD and controls using microarray, then the candidate circRNAs were validated in another PD cohort. The possible functions of these candidate circRNAs were analyzed using Gene Ontology (GO) analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, and the regulatory networks of these candidate circRNAs were constructed through circRNA-miRNA-mRNA regulatory networks, protein-protein interaction (PPI) networks, and transcription factor-circRNA networks. The results indicated that hsa_circRNA_101275, hsa_circRNA_103730, and hsa_circRNA_038416 were significantly more highly expressed in patients with PD, while hsa_circRNA_102850 was lower expressed in patients with PD when compared with controls. A circRNA panel combining the four differentially expressed circRNA showed a high diagnostic ability to distinguish patients with PD from controls (AUC = 0.938). Furthermore, GO and KEGG analysis showed these candidate circRNAs were enriched in PI3K-Akt and MAPK signaling pathways. We established circRNA-miRNA-mRNA regulatory networks and identified 10 hub genes (ESR1, PTEN, SHC1, IGF1R, SMAD2, KRAS, MDM2, HIF1A, BMP4, and ACVR2B) were closely related to PD by using PPI network analysis. Besides, these circRNAs were predicted to be regulated through tyrosine hydroxylase (TH)-relevant transcription factors such as GATA2 and GATA3. In conclusion, our results suggest that the circRNA panel and the established circRNA-miRNA-mRNA regulation networks might provide potential novel biomarkers and therapeutic targets for PD.