X-inactivation of HSD17B10 revealed by cDNA analysis in two female patients with 17β-hydroxysteroid dehydrogenase 10 deficiency

17β-Hydroxysteroid dehydrogenase 10 (HSD10) is a mitochondrial enzyme involved in the degradation pathway of isoleucine and branched-chain fatty acids. The gene encoding HSD10, HSD17B10, has been reported as one of the few genes that escapes X-inactivation. We previously studied two female patients with HSD10 deficiency, one of them was severely affected and the other presented a mild phenotype. To elucidate as to why these two carriers were so differently affected, cDNA analyses were performed. The HSD17B10 cDNA of eight control cell lines, two hemizygous patients and two carriers was obtained from cultured fibroblasts, amplified by PCR and sequenced by standard methods. All HSD17B10 cDNAs were quantified by real-time PCR. In the fibroblasts of the female patient who presented with the severe phenotype, only the mutant allele was identified in the cDNA sequence, which was further confirmed by relative quantification (RQ) of HSD17B10 cDNA. This is in agreement with an unfavourable X-inactivation. The other female patient, with slight clinical affectation, showed the presence of both mutant and wild-type alleles in the cDNA sequence, which was confirmed by RQ of HSD17B10 cDNA in fibroblasts. This is in line with normal X-inactivation and the expression of both alleles in different cells (functional mosaicism). RQ results of HSD17B10 cDNA did not differ significantly between male and female controls, which indicate that the genetic doses of mRNA of HSD17B10 was the same in both sexes. In conclusion, these results suggest that the HSD17B10 gene does not escape X-inactivation as has been reported previously.     

Running hot and cold: behavioral strategies, neural circuits, and the molecular machinery for thermotaxis in C. elegans and Drosophila

Like other ectotherms, the roundworm Caenorhabditis elegans and the fruit fly Drosophila melanogaster rely on behavioral strategies to stabilize their body temperature. Both animals use specialized sensory neurons to detect small changes in temperature, and the activity of these thermosensors governs the neural circuits that control migration and accumulation at preferred temperatures. Despite these similarities, the underlying molecular, neuronal, and computational mechanisms responsible for thermotaxis are distinct in these organisms. Here, we discuss the role of thermosensation in the development and survival of C. elegans and Drosophila, and review the behavioral strategies, neuronal circuits, and molecular networks responsible for thermotaxis behavior.     

Verrocchio,a Drosophila OB fold-containing protein,is a component of the terminin telomere-capping complex

Drosophila telomeres are elongated by transposition of specialized retroelements rather than telomerase activity, and are assembled independently of the terminal DNA sequence. Drosophila telomeres are protected by terminin, a complex that includes the HOAP (Heterochromatin Protein 1/origin recognition complex-associated protein) and Moi (Modigliani) proteins and shares the properties of human shelterin. Here we show that Verrocchio (Ver), an oligonucleotide/oligosaccharide-binding (OB) fold-containing protein related to Rpa2/Stn1, interacts physically with HOAP and Moi, is enriched only at telomeres, and prevents telomere fusion. These results indicate that Ver is a new terminin component; we speculate that, concomitant with telomerase loss, Drosophila evolved terminin to bind chromosome ends independently of the DNA sequence.     

Drosophila PTB promotes formation of high-order RNP particles and represses oskar translation

Local translation of asymmetrically enriched mRNAs is a powerful mechanism for functional polarization of the cell. In Drosophila, exclusive accumulation of Oskar protein at the posterior pole of the oocyte is essential for development of the future embryo. This is achieved by the formation of a dynamic oskar ribonucleoprotein (RNP) complex regulating the transport of oskar mRNA, its translational repression while unlocalized, and its translational activation upon arrival at the posterior pole. We identified the nucleo–cytoplasmic shuttling protein PTB (polypyrimidine tract-binding protein)/hnRNP I as a new factor associating with the oskar RNP in vivo. While PTB function is largely dispensable for oskar mRNA transport, it is necessary for translational repression of the localizing mRNA. Unexpectedly, a cytoplasmic form of PTB can associate with oskar mRNA and repress its translation, suggesting that nuclear recruitment of PTB to oskar complexes is not required for its regulatory function. Furthermore, PTB binds directly to multiple sites along the oskar 3′ untranslated region and mediates assembly of high-order complexes containing multiple oskar RNA molecules in vivo. Thus, PTB is a key structural component of oskar RNP complexes that dually controls formation of high-order RNP particles and translational silencing.     

PPARG,AGTR1, CXCL16 and LGALS2 polymorphisms are correlated with the risk for coronary heart disease

Purpose: Our study was designed to explore the interaction between genes of PPARG, AGTR1, CXCL16 and LGALS2 and further investigate the association between genes polymorphisms and coronary heart disease (CHD). Methods: 90 CHD patients and 80 healthy individuals were enrolled in our study. Gene chip technology was used for checking four single nucleotide polymorphisms (SNPs) (PPARG rs1152002, AGTR1 rs5186, CXCL16 rs3744700 and LGALS2 rs7291467). MDR software was used to analyze gene-gene interactions. Odds ratio (OR) with 95% confidence interval (CI) were employed to evaluate the association of genes and CHD risk. Results: Genotypes and alleles distribution in case and control groups showed significant difference (P<0.05). And there exists interaction among genes. The model of PPARG×CXCL16 showed effects on the occurrence of CHD (OR=2.92, 95% CI=1.44-5.94). Meanwhile, the PPARG×AGTR1×CXCL16×LGALS2 model was associated with CHD susceptibility (OR=3.97, 95% CI=2.01-7.84). Moreover, we found that PPARG×LGALS2×CXCL16, was the best interaction model and it could significantly increase the risk for CHD (OR=3.37, 95% CI=1.71-6.63). Conclusion: PPARG rs1152002, AGTR1 rs5186, CXCL16 rs3744700 and LGALS2 rs7291467 polymorphisms may be closely related to the development of CHD. Moreover, there exist gene-gene interactions among these susceptibility genes.     

A genetic screen for sleep and circadian mutants reveals mechanisms underlying regulation of sleep in Drosophila

STUDY OBJECTIVES: In order to characterize the genetic mechanisms underlying sleep, we have carried out a large-scale screen in Drosophila to identify short-sleeping mutants. The objectives of this study were as follows: (1) characterize the phenotypes of the shortest-sleeping mutants; (2) examine whether changes in arousal threshold or sleep homeostasis underlie short-sleeping phenotypes; (3) clone a gene affected in one of the shortest sleepers; and (4) investigate whether circadian mutants can be identified using light:dark (L:D) locomotor data obtained for studying sleep behavior. DESIGN: Locomotor activity was measured using the Drosophila Activity Monitoring System in a 12:12 L:D cycle. SETTING: Drosophila research laboratory. Participants: Adult flies from the 2nd chromosome Zuker collection, which contain mutations in most of the nonessential genes on the Drosophila 2nd chromosome. MEASUREMENTS AND RESULTS: Our analysis of sleep characteristics suggests that daily activity (but not waking activity) correlates with daily sleep time and that defects in sleep maintenance are more common than defects in sleep initiation. Our shortest sleepers have intact or increased sleep rebound following sleep deprivation but show reduced thresholds for arousal. Molecular analysis of one of the short-sleeping lines indicates that it is a novel allele of a dopamine transporter (DAT). Finally, we describe a novel approach for identifying circadian mutants using L:D data. CONCLUSIONS: Our data suggest that most short-sleeping mutant phenotypes in Drosophila are characterized by an inability to stay asleep, most likely because of a reduced arousal threshold.     

Site-specific methylation of placental HSD11B2 gene promoter is related to intrauterine growth restriction

Intrauterine growth restriction (IUGR) is associated with detrimental effects on neurodevelopmental progress in childhood and higher risk of degenerative diseases in adulthood. Placental 11β-hydroxysteroid dehydrogenase (HSD11B2) is a key gene involved in glucocorticoid metabolism, which in turn seems to be related to fetal growth impairment. As reduction of placental HSD11B2 gene expression has been associated with reduced human fetal growth, and methylation of HSD11B2 gene promoter has been shown to have an important role in HSD11B2 gene repression, we seek to investigate the relationship between IUGR and HSD11B2 gene promoter methylation in human placentas. We found that methylation levels of all studied CpG sites were significantly higher in IUGR newborns than those in controls. Further, methylation levels of the first and the third CpG sites were inversely associated with measures of fetal growth (birth weight and ponderal index). In addition, consistent with the above negative correlation, methylation levels of the first and the third CpG sites were inversely associated with HSD11B2 gene expression. These results together show a link between the site-specific methylation of placental HSD11B2 promoter and the development of IUGR.     

IL-10 Polymorphisms and Tuberculosis Susceptibility: An Updated Meta-Analysis

Purpose

The association of interleukin-10 (IL-10) polymorphisms (-1082G/A, -819C/T, -592A/C) and interleukin-6 (IL-6) poly-morphisms (-174G/C) with tuberculosis (TB) risk has been widely reported. However, the results are controversial. To clarify the role of these polymorphisms in TB, we performed a meta-analysis of all available and relevant published studies.

Materials and Methods

Based on comprehensive searches of the PubMed, Medline, Embase, Web of Science, Elsevier Science Direct and Cochrane Library database, we identified outcome data from all articles estimating the association between IL-10 and IL-6 polymorphisms and TB risk.

Results

The results indicated significant association of the allele model, heterozygous model and dominant model of IL-6 -174G/C polymorphism with decreased risk of TB. In the stratified analysis by ethnicity, significantly increased risk was observed for IL-10 -1082G/A polymorphism in Europeans under recessive model, for IL-10 -819C/T polymorphism in Asians under heterozygous model and dominant model and IL-10 -592A/C polymorphism in Asians under Allele model, homozygous model and recessive model. Moreover, significantly decreased risk of TB was associated with Asians for IL-6 -174C/G polymorphism in allele model, heterozygous model and dominant model. We also performed the analyses by sample types in IL-10 -1082G/A polymorphism, and observed significantly increased TB risk in mixed group under homozygous model.

Conclusion

The results suggested that the IL-10 -1082G/A polymorphism is associated with increased TB risk in Europeans, while IL-10 -819C/T and IL-10 -592A/C polymorphisms in Asians. However, IL-6 -174G/C polymorphism might be a genetic risk factor that decreases TB susceptibility in Asians.     

Single-nucleotide polymorphism analysis of GH, GHR,and IGF-1 genes in minipigs

Tibetan (TB) and Bama (BM) miniature pigs are two popular pig breeds that are used as experimental animals in China due to their small body size. Here, we analyzed single-nucleotide polymorphisms (SNPs) in gene fragments that are closely related to growth traits [growth hormone (GH), growth hormone receptor (GHR), and insulin-like growth factor (IGF)-1)] in these pig breeds and a large white (LW) control pig breed. On the basis of the analysis of 100 BMs, 108 TBs, and 50 LWs, the polymorphic distribution levels of GH, GHR, and IGF-1 were significantly different among these three pig breeds. According to correlation analyses between SNPs and five growth traits - body weight (BW), body length (BL), withers height (WH), chest circumference (CC), and abdomen circumference (AC) - three SNP loci in BMs and four SNP loci in TBs significantly affected growth traits. Three SNP sites in BMs and four SNP sites in TBs significantly affected growth traits. SNPs located in the GH gene fragment significantly affected BL and CC at locus 12 and BL at locus 45 in BMs, and also BW, WH, CC, and AC at locus 45 and WH and CC at locus 93 in TBs. One SNP at locus 85 in the BM GHR gene fragment significantly affected all growth traits. All indices were significantly reduced with a mixture of alleles at locus 85. These results provide more information regarding the genetic background of these minipig species and indicate useful selection markers for pig breeding programs.     

Atg7-dependent autophagy promotes neuronal health, stress tolerance, and longevity but is dispensable for metamorphosis in Drosophila

Autophagy, a cellular process of cytoplasmic degradation and recycling, is induced in Drosophila larval tissues during metamorphosis, potentially contributing to their destruction or reorganization. Unexpectedly, we find that flies lacking the core autophagy regulator Atg7 are viable, despite severe defects in autophagy. Although metamorphic cell death is perturbed in Atg7 mutants, the larval-adult midgut transition proceeds normally, with extended pupal development compensating for reduced autophagy. Atg7-/- adults are short-lived, hypersensitive to nutrient and oxidative stress, and accumulate ubiquitin-positive aggregates in degenerating neurons. Thus, normal levels of autophagy are crucial for stress survival and continuous cellular renewal, but not metamorphosis.     

Misexpression screen delineates novel genes controlling Drosophila lifespan

In an initial preliminary screen we identified factors associated with controlling Drosophila aging by examining longevity in adults where EP elements induced over-expression or antisense-RNA at genes adjacent to each insertion. Here, we study 45 EP lines that initially showed at least 10% longer mean lifespan than controls. These 45 lines and a daughterless (da)-Gal4 stock were isogenized into a CS10 wild-type background. Sixteen EP lines corresponding to 15 genes significantly extended lifespan when their target genes were driven by da-Gal4. In each case, the target genes were seen to be over-expressed. Independently derived UAS-gene transgenic stocks were available or made for two candidates: ImpL2 which is ecdysone-inducible gene L2, and CG33138, 1,4-alpha-glucan branching enzyme. With both, adult lifespan was increased upon over-expression via the GeneSwitch inducible Gal4 driver system. Several genes in this set of 15 correspond to previously discovered longevity assurance systems such as insulin/IGF-1 signaling, gene silencing, and autophagy; others suggest new potential mechanisms for the control of aging including mRNA synthesis and maturation, intracellular vesicle trafficking, and neuroendocrine regulation.     

Identification and characterization of a human IL-10 receptor antagonist

Interleukin-10 (IL-10) is an anti-inflammatory cytokine that works through IL-10 receptor alpha subunit- and suppresses immune responses in many infectious diseases such as leishmaniasis as well as in cancer. Therefore, in order to restore the host-protective immune responses in such diseases, an antagonist to this cytokine is a pressing need. Herein, using phage peptide library display, we have identified a dodecameric peptide that functions as an antagonist to human IL-10 receptor in an IL-10-induced STAT3 phosphorylation assay. The peptide antagonist’s ability to restore anti-leishmanial function in CD40-activated macrophages was also tested. We observed that the peptide reduced IL-10-induced STAT-3 phosphorylation and enhanced CD40-activated leishmanial functions in macrophages.     

Drosophila Minus is required for cell proliferation and influences Cyclin E turnover

Turnover of cyclins plays a major role in oscillatory cyclin-dependent kinase (Cdk) activity and control of cell cycle progression. Here we present a novel cell cycle regulator, called minus, which influences Cyclin E turnover in Drosophila. minus mutants produce defects in cell proliferation, some of which are attributable to persistence of Cyclin E. Minus protein can interact physically with Cyclin E and the SCF Archipelago/Fbw7/Cdc4 ubiquitin–ligase complex. Minus does not affect dMyc, another known SCF^Ago substrate in Drosophila. We propose that Minus contributes to cell cycle regulation in part by selectively controlling turnover of Cyclin E.     

Status of allele frequency and diversity of Plasmodium falciparum msp1, msp2 and glurp before implementation of an artemisinin-based combined therapy in Northwestern Colombia.

Introduction:

The status of msp1, msp2 and glurp allele frequency and the diversity of Plasmodium falciparum in Northwestern Colombia before the implementation of an artemisinin-combined therapy have been explored only by a few authors and in a relatively small number of samples from this highly endemic region.

Objective:

To evaluate the frequency of msp1, msp2, and glurp alleles and the diversity of P. falciparum in two Colombian regions before the use of an artemisinin-combined therapy.

Methods:

This study was part of a major anti-malarial efficacy trial designed as a random, clinically-controlled study for which 224 subjects were recruited. Region 2 of msp1 and msp2 (central region) were amplified by a nested PCR; glurp (region R2) was amplified by a semi-nested PCR.

Results:

For msp1, five genotypes were observed, representing the K1, MAD20, and RO33 allelic families. All samples corresponded to a MAD20 150 bp allele. For msp2 (IC family), two alleles were detected and for glurp, eight were observed. A total 33 haplotypes were detected.

Conclusions:

Analysis of glurpcan be used to successfully genotype parasite populations in the new studies in Colombia aimed at exploring Plasmodium spp population dynamics. In addition, analysis of msp1 and msp2 can also be of value for comparisons with past studies, but not when the objective is to study parasites obtained from the same patient in a reduced period of time; for instance, during treatment efficacy studies.     

A Leishmania infantum cytosolic tryparedoxin activates B cells to secrete interleukin-10 and specific immunoglobulin

The immune evasion mechanisms of pathogenic trypanosomatids involve a multitude of phenomena such as the polyclonal activation of lymphocytes, cytokine modulation and the enhanced detoxification of oxygen reactive species. A trypanothione cascade seems to be involved in the detoxification process. It was recently described and characterized a tryparedoxin (LiTXN1) involved in Leishmania infantum cytoplasmatic hydroperoxide metabolism. LiTXN1 is a secreted protein that is up-regulated in the infectious form of the parasite, suggesting that it may play an important role during infection. In the present study, we investigated whether recombinant LiTXN1 (rLiTXN1) affects T- and B-cell functions in a murine model. We observed a significant increase in the CD69 surface marker on the B-cell population in total spleen cells and on isolated B cells from BALB/c mice after in vitro rLiTXN1 stimulus. Activated B-cells underwent further proliferation, as indicated by increased [(3)H]thymidine incorporation. Cytokine quantification showed a dose-dependent up-regulation of interleukin (IL)-10 secretion. B cells were identified as a source of this secretion. Furthermore, intraperitoneal injection of rLiTXN1 into BALB/c mice triggered the production of elevated levels of rLiTXN1-specific antibodies, predominantly of the immunoglobulin M (IgM), IgG1 and IgG3 isotypes, with a minimum reactivity against other heterologous antigens. Taken together, our data suggest that rLiTXN1 may participate in immunopathological processes by targeting B-cell effector functions, leading to IL-10 secretion and production of specific antibodies.     

Roles for the Yb body components Armitage and Yb in primary piRNA biogenesis in Drosophila

PIWI-interacting RNAs (piRNAs) protect genome integrity from transposons. In Drosophila ovarian somas, primary piRNAs are produced and loaded onto Piwi. Here, we describe roles for the cytoplasmic Yb body components Armitage and Yb in somatic primary piRNA biogenesis. Armitage binds to Piwi and is required for localizing Piwi into Yb bodies. Without Armitage or Yb, Piwi is freed from the piRNAs and does not enter the nucleus. Thus, piRNA loading is required for Piwi nuclear entry. We propose that a functional Piwi-piRNA complex is formed and inspected in Yb bodies before its nuclear entry to exert transposon silencing.     

Interleukin-10 but not interleukin-18 may be associated with the immune response against well-differentiated thyroid cancer

OBJECTIVES:

The aim of this study was to investigate the role of the interleukin-18 +105A/C and interleukin-10 -1082A/G germline polymorphisms in the development and outcome of differentiated thyroid carcinoma associated or not with concurrent thyroiditis.

METHODS:

We studied 346 patients with differentiated thyroid carcinomas, comprising 292 papillary carcinomas and 54 follicular carcinomas, who were followed up for 12-298 months (mean 76.10±68.23 months) according to a standard protocol. We genotyped 200 patients and 144 control individuals for the interleukin-18 +105A/C polymorphism, and we genotyped 183 patients and 137 controls for the interleukin-10 -1082A/G polymorphism.

RESULTS:

Interleukin-18 polymorphisms were not associated with chronic lymphocytic thyroiditis or any clinical or pathological feature of tumor aggressiveness. However, there was an association between the presence of interleukin-10 variants and chronic lymphocytic thyroiditis. Chronic lymphocytic thyroiditis was present in 21.74% of differentiated thyroid carcinoma patients, most frequently affecting women previously diagnosed with Hashimoto''s thyroiditis who had received a lower ¹³¹I cumulative dose and did not present lymph node metastases.

CONCLUSIONS:

We conclude that the inheritance of a G allele at the interleukin-10 -1082A/G polymorphism may favor a concurrent thyroid autoimmunity in differentiated thyroid carcinoma patients, and this autoimmunity may favor a better prognosis for these patients.