Single nucleotide polymorphisms of GEMIN3 modify the risk of primary Sjögren's syndrome in female patients.

BACKGROUND: MicroRNA (miRNA)-processing machinery may modify the risk of primary Sjögren's syndrome (pSS) by altering miRNA expression profiles. Inflammatory cytokines and reactive oxygen species (ROS) are also involved in pSS; however, the role of altered miRNAs expression in its pathogenesis is still unclear. We aimed to evaluate the relationship between single-nucleotide polymorphisms (SNPs) in miRNA processing machinery genes, including XPO5 (rs11077), RAN (rs14035), Dicer (rs3742330), TNRC6B (rs9623117), GEMIN3 (rs197412), and GEMIN4 (rs2740348), and the risk of pSS in female patients. The potential associations of cytokines and ROS with pSS-susceptible SNPs were also evaluated. METHODS: The SNPs confirmed by polymerase chain reaction ligase detection reaction were genotyped in 74 female patients with pSS and 77 controls. The relationship was analyzed by Student's t-test, Wilcoxon rank-sum test, chi-square test, Pearson's correlation test, and binary logistic regression analysis. RESULTS: For rs197412 of the GEMIN3 gene, the genotype TT carrier was associated with a 2.172-fold increased risk for pSS when compared with that of CT+CC carrier (odds ratio: 2.172, 95% CI, 1.133-4.166, p=0.019). Simultaneously, the pSS-susceptible TT carriers were associated with increased interferon-γ (IFN-γ) (P<0.001) and tumor necrosis factor-α (TNF-α) (P=0.003) levels when compared with that of CT+CC genotype carriers in female patients with pSS. The subsequent analysis also showed a weak positive correlation between IFN-γ and TNF-α levels (r=0.271, P=0.019). CONCLUSION: The predictors of GEMIN3 SNPs might modify pSS development in females by mediating the expression of miRNAs and therefore regulate the levels of IFN-γ and TNF-α.

CXCL5 activates CXCR2 in nociceptive sensory neurons to drive joint pain and inflammation in experimental gouty arthritis.

Gouty arthritis evokes joint pain and inflammation. Mechanisms driving gout pain and inflammation remain incompletely understood. Here we show that CXCL5 activates CXCR2 expressed on nociceptive sensory neurons to drive gout pain and inflammation. CXCL5 expression was increased in ankle joints of gout arthritis model mice, whereas CXCR2 showed expression in joint-innervating sensory neurons. CXCL5 activates CXCR2 expressed on nociceptive sensory neurons to trigger TRPA1 activation, resulting in hyperexcitability and pain. Neuronal CXCR2 coordinates with neutrophilic CXCR2 to contribute to CXCL5-induced neutrophil chemotaxis via triggering CGRP- and substance P-mediated vasodilation and plasma extravasation. Neuronal Cxcr2 deletion ameliorates joint pain, neutrophil infiltration and gait impairment in model mice. We confirmed CXCR2 expression in human dorsal root ganglion neurons and CXCL5 level upregulation in serum from male patients with gouty arthritis. Our study demonstrates CXCL5-neuronal CXCR2-TRPA1 axis contributes to gouty arthritis pain, neutrophil influx and inflammation that expands our knowledge of immunomodulation capability of nociceptive sensory neurons.

The BTB-ZF gene Bm-mamo regulates pigmentation in silkworm caterpillars.

The color pattern of insects is one of the most diverse adaptive evolutionary phenotypes. However, the molecular regulation of this color pattern is not fully understood. In this study, we found that the transcription factor Bm-mamo is responsible for black dilute (bd) allele mutations in the silkworm. Bm-mamo belongs to the BTB zinc finger family and is orthologous to mamo in Drosophila melanogaster. This gene has a conserved function in gamete production in Drosophila and silkworms and has evolved a pleiotropic function in the regulation of color patterns in caterpillars. Using RNAi and clustered regularly interspaced short palindromic repeats (CRISPR) technology, we showed that Bm-mamo is a repressor of dark melanin patterns in the larval epidermis. Using in vitro binding assays and gene expression profiling in wild-type and mutant larvae, we also showed that Bm-mamo likely regulates the expression of related pigment synthesis and cuticular protein genes in a coordinated manner to mediate its role in color pattern formation. This mechanism is consistent with the dual role of this transcription factor in regulating both the structure and shape of the cuticle and the pigments that are embedded within it. This study provides new insight into the regulation of color patterns as well as into the construction of more complex epidermal features in some insects.

Mitochondrial displacement loop region single nucleotide polymorphisms and mitochondrial DNA copy number associated with risk of ankylosing spondylitis.

AIM: The pathogenesis of ankylosing spondylitis (AS) seems to be associated with genetics, the environment, heredity, and oxidative stress. Single nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) region of mitochondrial DNA (mtDNA) and mtDNA copy number were investigated for their correlation with AS patients. METHODS: This study included 83 AS patients and 100 healthy controls from the Second Hospital of Hebei Medical University. DNAs were extracted from blood samples for polymerase chain reaction analysis and quantitative real-time polymerase chain reaction analysis. Plasma reactive oxygen species (ROS) levels were measured by fluorescent probe technology. RESULTS: The distribution frequencies of the minor alleles of nucleotides 16304C (p = .037), 16311C (p = .027), and 152C (p = .034) were remarkably higher in AS patients than in healthy controls, which indicated that the16304C, 16311C, and 152C alleles were correlated with an increased risk of AS. Simultaneously, mtDNA copy number was statistically higher in patients with AS compared with controls (1.450 ± 0.876 versus 0.835 ± 0.626, p < .001). We also observed an increased ROS generation in AS patients compared with controls (27 066.169 ± 18 364.819 versus 14 758.330 ± 5854.946, p < .001) subsequently. In addition, the AS susceptible SNP 16311C is associated with high ROS levels (35 065.177 ± 26 999.934 vs. 25 005.818 ± 14 999.495, p = .043). CONCLUSION: Our study demonstrated that SNPs in the mtDNA D-loop could be AS risk biomarkers with the potential to promote oxidative stress levels; mtDNA copy number-induced mitochondrial dysfunction may also be involved in AS pathogenesis.

Polymorphisms in microRNA binding site of SET8 regulate the risk of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a complex, heterogeneous, progressive and long-term autoimmune disease characterized by symmetrical joint inflammation and bone erosion. The etiology of RA is unclear, but its pathogenesis is associated with oxidative stress and inflammatory cytokines. Single nucleotide polymorphisms (SNPs) in the microRNA (miRNA)-binding sites modify the development of rheumatic disease by regulating the expression of target genes. The present study investigated whether SNPs in the miRNA binding site in the 3' untranslated region (3'-UTR) of SET domain containing (lysine methyltransferase) 8 (SET8) and Keratin 81 (KRT81), namely rs16917496 and rs3660, respectively, were associated with the occurrence of RA. The polymerase chain reaction-ligase detection reaction assay showed that the distribution frequencies of the CC genotype (P=0.025) of SNP rs16917496 in SET8 were significantly higher in patients with RA than in healthy controls, which indicated that the CC genotype was associated with an increased risk of RA. SET8 expression in the blood samples of CC genotype carriers was lower than that of TT genotype carriers. Moreover, the CC genotype carriers exhibited higher reactive oxygen species (ROS) levels (1011.500±536.426 vs. 548.616±190.508, P=0.032) and lower interleukin-10 (IL-10) levels (P<0.001). The present study demonstrated that SNP rs16917496 in the 3'-UTR of SET8 was a predictor of RA risk and may regulate RA development by mediating expression of SET8, thereby regulating the levels of ROS and IL-10.

Risk-associated single nucleotide polymorphisms of mitochondrial D-loop mediate imbalance of cytokines and redox in rheumatoid arthritis.

BACKGROUND: We have identified rheumatoid arthritis (RA) risk-associated single nucleotide polymorphisms (SNPs) in the mitochondrial displacement loop (D-loop) including the major alleles of nucleotides 195T/C, 16260C/T, and 16519C/T as well as the minor alleles of nucleotides 146T/C and 150C/T previously. OBJECTIVE: We evaluated the potential relationships of these SNPs with status for oxidative stress and inflammation cytokines. METHODS: The DNA was extracted from blood samples of RA patients, and the SNPs of DNA D-loop were verified by polymerase chain reaction amplification and sequence analysis. Serum levels of inflammatory cytokines including interferon-γ (IFN-γ), interleukin-2 (IL-2), IL-6, IL-10, and tumor necrosis factor-α (TNF-α) were determined by cytometric bead array. Plasma reactive oxygen species (ROS) levels were measured by fluorescent probe technology. RESULTS: The RA risk-related allele 16519C was significantly associated with high IFN-γ levels (100.576 ± 11.769 vs 64.268 ± 8.199, 95% confidence interval [CI] -66.317 to -6.299, P = 0.018). This allele also associated with ROS at borderline statistics level (619.295 ± 36.687 vs 526.979 ± 25.896, 95% CI -186.145 to -1.513, P = 0.054). The subsequent analysis also showed that the ROS levels were positively correlated with IFN-γ levels (R = 0.291, P = 0.002). Further analysis showed that RA patients with high C-reactive protein levels displayed a higher ROS level (P = 0.001). CONCLUSION: Our results imply that the 16519C allele of the mtDNA D-loop might promote ROS and IFN-γ levels by altering the replication and transcription of mtDNA, thereby modifying RA development. REMARK: The potential relationships of RA-associated SNPs in the mitochondrial D-loop with status for oxidative stress and inflammation were evaluated. The 16519C allele of the mtDNA D-loop might promote ROS and IFN-γ levels by altering the replication and transcription of mtDNA to modify RA development.

Mitochondrial Displacement Loop Region SNPs Modify Sjögren's Syndrome Development by Regulating Cytokines Expression in Female Patients.

Mitochondrial dysfunction could induce innate immune response with cytokines releasing to initiate Sjögren's syndrome (SS) onset. Single nucleotide polymorphisms (SNPs) in the mitochondrial displacement loop (D-loop) and mitochondrial DNA (mtDNA) copy number of female SS patients were evaluated for their association with SS in female patients. At the nucleotide site of 152, 16304, 16311 and 16362 in the D-loop, the frequencies for the minor alleles of 152C (p = 0.040, odds ratio [OR] = 0.504), 16304C (p = 0.045, OR = 0.406), 16311C (p = 0.045, OR = 0.406) and 16362C (p = 0.028, OR = 0.519) were significantly higher in the SS patients than those in the female controls, which indicated that 152,C, 16304C, 16311C, and 16362C allele in the D-loop of mtDNA were associated with the risk of SS. Meanwhile, the excessive SNPs were accumulated in D-loop region of SS patients (8.955 ± 2.028 versus 7.898 ± 1.987, p < 0.001, 95% confidence interval [CI]: 0.477-1.637) and mtDNA copy number increased in SS patients (1.509 ± 0.836 versus 1.221 ± 0.506, p = 0.006, 95% CI: 0.086-0.490) by a case-control analysis. The subsequent analysis showed that SS risk-related allele 16311C was associated with higher IL-2 levels (p = 0.010) at significantly statistical level whereas 152C associated with lower IL-10 levels (p = 0.058) at a borderline statistical levels. Our findings suggest that mitochondrial D-loop SNPs are predictors for SS risk, it might modify the SS development by regulating cytokine expression.

The SNPs of mitochondrial DNA displacement loop region and mitochondrial DNA copy number associated with risk of polymyositis and dermatomyositis.

Oxidative damage-induced mitochondrial dysfunction may activate muscle catabolism and autophagy pathways to initiate muscle weakening in idiopathic inflammatory myopathies (IIMs). In this study, Single nucleotide polymorphisms (SNPs) in the mitochondrial displacement loop (D-loop) and mitochondrial DNA (mtDNA) copy number were assessed and their association with the risk of polymyositis and dermatomyositis (PM/DM) was evaluated. Excessive D-loop SNPs (8.779 ± 1.912 vs. 7.972 ± 1.903, p = 0.004) correlated positively with mtDNA copy number (0.602 ± 0.457 vs. 0.300 ± 0.118, p < 0.001). Compared with that of the controls, the mtDNA of PM/DM patients showed D-loop SNP accumulation. In addition, the distribution frequencies of 16304C (p = 0.047) and 16519C (p = 0.043) were significantly higher in the patients with PM/DM. Subsequent analysis showed that reactive oxygen species (ROS) generation was increased in PM/DM patients compared with that in the controls (18,477.756 ± 13,574.916 vs. 14,484.191 ± 5703.097, p = 0.012). Further analysis showed that the PM/DM risk-related allele 16304C was significantly associated with lower IL-4 levels (p = 0.021), while 16519C had a trend to be associated with higher IL-2 expression (p = 0.064). The allele 16519C was associated with a positive antinuclear antibody (ANA) status in PM/DM patients (p = 0.011). Our findings suggest that mitochondrial D-loop SNPs could be potential biomarkers for PM/DM risk and these SNPs associated with cytokine expression may be involved in the development of PM/DM. Further, mtDNA copy number-mediated mitochondrial dysfunction may precede the onset of PM/DM.

Identification of sequence polymorphisms in the mitochondrial deoxyribonucleic acid displacement-loop region as risk factors for systemic lupus erythematosus.

OBJECTIVES: This study aims to evaluate the relationship between sequence polymorphisms (SNPs) in the displacement-loop (D-loop) region of mitochondrial deoxyribonucleic acid (mtDNA) and systemic lupus erythematosus (SLE) in Chinese female patients. PATIENTS AND METHODS: This cross-sectional study was conducted between May 2017 and October 2017. The mtDNA was extracted from the peripheral blood of 97 female SLE patients (mean age 40.8 years; range, 20 to 79 years) and 108 age-matched healthy controls (mean age 48.7 years; range, 22 to 78 years). The SNPs of mtDNA D-loop were verified by polymerase chain reaction amplification and sequence analysis. The allele frequencies of D-loop region were compared by the Chi-square test between SLE and control groups. RESULTS: The SNP accumulation in SLE patients was significantly higher than that in the controls (p=0.027, 95% confidence interval [CI]: 0.075, 1.210). The frequencies of the major alleles of the nucleotides 73G/A (p<0.001, odds ratio [OR]=1.241) and 195T/C (p=0.047, OR=4.318) as well as the minor allele of nucleotide 199T/C (p=0.048, OR=0.279) were significantly higher in the SLE patients than in the controls, which indicated that 73G, 195T and 199C allele in the D-loop of mtDNA were associated with the risk of SLE. Further analysis indicated that the reactive oxygen species level in the SLE patients was significantly higher than that of controls (mean fluorescence intensity ± standard deviation: 3054.333±256.099 vs. 2099.167±599.662, p=0.009, 95% CI: 321.243, 1589.091). CONCLUSION: This study indicated the SNPs in the mtDNA may associated with the risk of SLE. Analysis of SNPs in the mitochondrial D-loop may help identify individuals who are at high risk of developing SLE.

Recent advances in the epidemiology and genetics of acute intermittent porphyria.

Acute intermittent porphyria (AIP) is a dominant inherited disorder with a low penetrance that is caused by mutations in the gene coding for hydroxymethylbilane synthase (HMBS). Information about the epidemiology and molecular genetic features of this rare disorder is crucial to clinical research, and particularly to the evaluation of new treatments. Variations in the prevalence and penetrance of AIP in various studies may due to the different inclusion criteria and methods of assessment. Here, the prevalence and penetrance of AIP are analyzed systematically, and the genetic traits of different populations and findings regarding the genotype-phenotype correlation are summarized. In addition, quite a few studies have indicated that AIP susceptibility was affected by other factors, such as modifying genes. Findings regarding possible modifying genes are documented here, helping to reveal the pathogenesis of and treatments for AIP. The status of research on AIP in China reveals the lack of epidemiological and genetic studies of the Chinese population, a situation that needs to be promptly remedied.

Comparison of the diagnostic value of four scoring systems in primary sjögren's syndrome patients.

PURPOSE: We attempted to evaluate the diagnostic value of different salivary gland ultrasonography (SGUS) scoring systems for primary sjögren's syndrome (pSS). METHODS: Total 134 patients with pSS and 109 non-SS sicca controls were included in our study. All the cases were evaluated by four scoring systems (such as 0-16 SGUS, 0-3 SGUS, Parotid glands and Submandibular salivary glands scoring system). The receiver operating characteristic (ROC) analysis was performed for the four scoring systems. RESULTS: The mean scores of pSS patients were significantly higher than that of controls by four scoring systems (P<0.01). The AUC (area under the curve) of (0-16) SGUS scoring system (0.916) was higher than Submandibular salivary glands scoring system (0.885) (P=0.016). No significant difference of AUC was observed in (0-3) SGUS scoring system, compared with 0-16, parotid gland and submandibular salivary glands scoring system. The optimal cutoff value of (0-16) SGUS, (0-3) SGUS, Parotid gland, Submandibular salivary glands scoring system was 5, 2, 3, 2, respectively. There was no significant difference in the sensitivity and specificity of the four scoring systems. CONCLUSION: The simplified parotid gland scoring system may be the simplified and feasible method for pSS diagnosis.

Comparative analysis of the integument transcriptomes of the black dilute mutant and the wild-type silkworm Bombyx mori.

The insect cuticle is a critical protective shell that is composed predominantly of chitin and various cuticular proteins and pigments. Indeed, insects often change their surface pigment patterns in response to selective pressures, such as threats from predators, sexual selection and environmental changes. However, the molecular mechanisms underlying the construction of the epidermis and its pigmentation patterns are not fully understood. Among Lepidoptera, the silkworm is a favorable model for color pattern research. The black dilute (bd) mutant of silkworm is the result of a spontaneous mutation; the larval body color is notably melanized. We performed integument transcriptome sequencing of the wild-type strain Dazao and the mutant strains +/bd and bd/bd. In these experiments, during an early stage of the fourth molt, a stage at which approximately 51% of genes were expressed genome wide (RPKM ≥1) in each strain. A total of 254 novel transcripts were characterized using Cuffcompare and BLAST analyses. Comparison of the transcriptome data revealed 28 differentially expressed genes (DEGs) that may contribute to bd larval melanism, including 15 cuticular protein genes that were remarkably highly expressed in the bd/bd mutant. We suggest that these significantly up-regulated cuticular proteins may promote melanism in silkworm larvae.

A polymorphism at the microRNA binding site in the 3' untranslated region of RYR3 is associated with outcome in hepatocellular carcinoma.

OBJECTIVE: MicroRNAs can bind to the 3' untranslated regions (UTRs) of messenger RNAs, where they interfere with the translation of targeting genes, thereby regulating cell differentiation, apoptosis, and tumorigenesis. In this study, three microRNA binding site single nucleotide polymorphisms (SNPs) located in the 3' UTR of RYR3 (rs1044129), C14orf101 (rs4901706), and KIAA0423 (rs1053667) were genotyped to assess their relationships with the risks and outcomes of hepatocellular carcinoma (HCC). METHODS: The SNPs were genotyped with the ligation detection reaction method. Renilla luciferase reporter assays were used to measure the binding affinity between microRNA 367 and RYR3. Survival curves were calculated using the Kaplan-Meier method, and comparisons between the curves were made using the log-rank test. Multivariate survival analysis was performed using a Cox proportional hazards model. RESULTS: It was found that rs1044129 at the 3' UTR of RYR3 was related to postoperative survival in HCC, with the AA type associated with longer survival times as per the log-rank test. After adjusting with the Cox model, rs104419 was identified as an independent predictor of HCC survival (relative risk: 1.812; 95% confidence interval: 1.026-3.201; P=0.041). Luciferase analysis also indicated the different binding affinities between the SNPs of rs1044129 and microRNA 367. CONCLUSION: The SNP in the microRNA binding site of RYR3 can be used as a valuable biomarker when predicting HCC outcomes.