RNA-Seq Reveals Acute Manganese Exposure Increases Endoplasmic Reticulum Related and Lipocalin mRNAs in Caenorhabditis elegans

Manganese (Mn) is an essential nutrient; nonetheless, excessive amounts can accumulate in brain tissues causing manganism, a severe neurological condition. Previous studies have suggested oxidative stress, mitochondria dysfunction, and impaired metabolism pathways as routes for Mn toxicity. Here, we used the nematode Caenorhabditis elegans to analyze gene expression changes after acute Mn exposure using RNA-Seq. L1 stage animals were exposed to 50 mM MnCl2 for 30 min and analyzed at L4. We identified 746 up- and 1828 downregulated genes (FDR corrected p < 0.05; two-fold change) that included endoplasmic reticulum related abu and fkb family genes, as well as six of seven lipocalin-related (lpr) family members. These were also verified by qRT-PCR. RNA interference of lpr-5 showed a dramatic increase in whole body vulnerability to Mn exposure. Our studies demonstrate that Mn exposure alters gene transcriptional levels in different cell stress pathways that may ultimately contribute to its toxic effects

Methylmercury exposure increases lipocalin related (lpr) and decreases activated in blocked unfolded protein response (abu) genes and specific miRNAs in Caenorhabditis elegans

Methylmercury (MeHg) is a persistent environmental and dietary contaminant that causes serious adverse developmental and physiologic effects at multiple cellular levels. In order to understand more fully the consequences of MeHg exposure at the molecular level, we profiled gene and miRNA transcripts from the model organism Caenorhabditis elegans. Animals were exposed to MeHg (10µM) from embryo to larval 4 (L4) stage and RNAs were isolated. RNA-seq analysis on the Illumina platform revealed 541 genes up- and 261 genes down-regulated at a cutoff of 2-fold change and false discovery rate-corrected significance q < 0.05. Among the up-regulated genes were those previously shown to increase under oxidative stress conditions including hsp-16.11 (2.5-fold), gst-35 (10.1-fold), and fmo-2(58.5-fold). In addition, we observed up-regulation of 6 out of 7 lipocalin related (lpr) family genes and down regulation of 7 out of 15 activated in blocked unfolded protein response (abu) genes. Gene Ontology enrichment analysis highlighted the effect of genes related to development and organism growth. miRNA-seq analysis revealed 6–8 fold down regulation of mir-37-3p, mir-41-5p, mir-70-3p, and mir-75-3p. Our results demonstrate the effects of MeHg on specific transcripts encoding proteins in oxidative stress responses and in ER stress pathways. Pending confirmation of these transcript changes at protein levels, their association and dissocation characteristics with interaction partners, and integration of these signals, these findings indicate broad and dynamic mechanisms by which MeHg exerts its harmful effects

The Draft Genome and Transcriptome of Panagrellus redivivus Are Shaped by the Harsh Demands of a Free-Living Lifestyle

Nematodes compose an abundant and diverse invertebrate phylum with members inhabiting nearly every ecological niche. Panagrellus redivivus (the “microworm”) is a free-living nematode frequently used to understand the evolution of developmental and behavioral processes given its phylogenetic distance to Caenorhabditis elegans. Here we report the de novo sequencing of the genome, transcriptome, and small RNAs of P. redivivus. Using a combination of automated gene finders and RNA-seq data, we predict 24,249 genes and 32,676 transcripts. Small RNA analysis revealed 248 microRNA (miRNA) hairpins, of which 63 had orthologs in other species. Fourteen miRNA clusters containing 42 miRNA precursors were found. The RNA interference, dauer development, and programmed cell death pathways are largely conserved. Analysis of protein family domain abundance revealed that P. redivivus has experienced a striking expansion of BTB domain-containing proteins and an unprecedented expansion of the cullin scaffold family of proteins involved in multi-subunit ubiquitin ligases, suggesting proteolytic plasticity and/or tighter regulation of protein turnover. The eukaryotic release factor protein family has also been dramatically expanded and suggests an ongoing evolutionary arms race with viruses and transposons. The P. redivivus genome provides a resource to advance our understanding of nematode evolution and biology and to further elucidate the genomic architecture leading to free-living lineages, taking advantage of the many fascinating features of this worm revealed by comparative studies

Retarded Growth and Deficits in the Enteric and Parasympathetic Nervous System in Mice Lacking GFRα2, a Functional Neurturin Receptor

AbstractGlial cell line–derived neurotrophic factor (GDNF) and a related protein, neurturin (NTN), require a GPI-linked coreceptor, either GFRα1 or GFRα2, for signaling via the transmembrane Ret tyrosine kinase. We show that mice lacking functional GFRα2 coreceptor (Gfra2−/−) are viable and fertile but have dry eyes and grow poorly after weaning, presumably due to malnutrition. While the sympathetic innervation appeared normal, the parasympathetic cholinergic innervation was almost absent in the lacrimal and salivary glands and severely reduced in the small bowel. Neurite outgrowth and trophic effects of NTN at low concentrations were lacking in Gfra2−/− trigeminal neurons in vitro, whereas responses to GDNF were similar between the genotypes. Thus, GFRα2 is a physiological NTN receptor, essential for the development of specific postganglionic parasympathetic neurons

Sex-specific mouse testosterone 16[alpha]-hydroxylase (cytochrome P450) genes : characterization and genetic and hormonal regulations

The molecular and genetic backround of sex-specific mouse steroid hydroxylase (cytochrome P450) isozymes was investigated. Mouse testosterone 16 α-hydroxylase activity in liver microsomes is apparently the sum of at least two isozymes: I-P45016α is the female-specific isozyme, while C-P45016α is predominantly expressed in males. Female-specific I-P45016α mRNA and testosterone 16α-hydroxylase activity levels in Balb/cJ male mouse liver are increased by castration from undetectable to levels as high as those seen in normal Balb/cJ females. Moreover, castration does not increase the mRNA or activity levels in the genetic 129/J male variant. The derepression in castrated males exhibits an autosomal codominant inheritance and is regulated by the Ripr locus in crosses between Balb/cJ and 129/J mice. (Noshiro, M. & Negishi, M. Biochemistry 27, 6444-6448, 1988). The genotypical background of Ripr locus was examined by first isolating the cDNA clones associated with I-P45016α - dependent mRNA and activity from Balb/cJ female mouse liver cDNA library. Next, cDNA libraries of castrated Balb/cJ male livers were screened and mouse clones were isolated. The Ripr locus was determined to consist of a cluster of at least three active genes, designated 16αoh-a, 16αoh-b, and 16αoh-d, of which 16αoh-a was always the major type expressed in normal Balb/cJ female liver and in castrated Balb/cJ male liver and was not expressed in 129/J mice. Nuclear run-on assays proved that the "I-P45016α" genes controlled by Ripr locus were transcriptionally regulated. Growth hormone was found to be the direct repressor of the genes in male mouse liver. Several polymorphic clones of the various "I-P45016α" cDNA clones and also of P450cb (one of five members of the C-P45016α gene family) cDNA clones were discovered. The possible role of aberrant splicing of P450 transcripts in P450 regulation was suggested. Next, the genes corresponding to 16αoh-A and 16αoh-B were isolated asmembers of a large multigene family (at least 16 genes) and characterized. Several interesting sequence motifs were discovered. The 16αoh gene family was also analyzed and organized into three different subfamilies according to 1st exon area BamHI fragments. Finally, transgenic mice were generated with a "I-P45016α" (16αoh-a) minigene or with C-P45016α/CAT, a recombinant gene construct containing the 5' -flanking region C-P45016α gene linked to the bacterial gene encoding chloramphenicol acetyltransferase (CAT). Expression of the transgene was detected in only one line carrying the C-P45016α/CAT - recombinant gene. The individual expressing the gene was male and the target organ was liver, indicating that the 5.5 kb flanking region of C-P45016α contains the necessary elements for expression in male liver. A single expressing transgenic among a large number of transgenic mice suggests that testosterone l6a-hydroxylase genes (forms of P450) are possibly sensitive for their chromosomal locations

Aikuisiällä syntyneen psyykkisen trauman huomioiminen toimintaterapiassa

Psyykkisen trauman aiheuttaa poikkeuksellisen uhkaava tai katastrofaalinen tapahtuma ja sillä voi olla merkittävä vaikutus ihmisen arkeen. Post-traumaattisen stressihäiriön etiologiset kriteerit täyttäviä stressitilanteita sattuu vuosittain arviolta 100 000 suomalaiselle, joista 20-30 %:lle kehittyy traumaperäinen stressihäiriö. Psyykkisen trauman huomioimisesta toimintaterapiassa on verrattavan vähän tietoa, erityisesti suomen kielellä. Opinnäytetyössä kuvataan mitä hyötyjä toimintaterapiainterventioista on ollut toiminnalliseen kokemukseen, toiminnalliseen suoriutumiseen ja osallistumiseen aikuisiällä syntyneen psyykkisen trauman saaneella henkilöllä. Työn tavoitteena oli koota ja tuottaa aiheeseen liittyvää tietoa toimintaterapeuteille kansainvälisten tutkimusten avulla. Opinnäytetyö toteutettiin integroituna kirjallisuuskatsauksena. Aineisto kerättiin PubMed, Cochrane ja CINAHL tietokantojen kautta. Lopulliseen aineiston analysointiin valittiin kuusi tutkimusta. Kaikki tutkimukset olivat vertaisarvioituja ja ne on julkaistu 2014-2020 välisenä aikana. Aineistoa tarkasteltiin toimintaterapialähtöisen Fisherin ja Marterellan (2019) Transactional Model of Occupation eli TMO –mallin kautta. Ryhmämuotoinen toimintaterapia oli yleisesti käytetty kuntoutusmuoto PTSD-oireisen henkilön toimintaterapiassa erityisesti veteraanien keskuudessa. Tutkimustuloksien perusteella voidaan ajatella, että toimintaterapiainterventioista on hyötyä. Tulosten perusteella voidaan todeta, että mielekäs toiminta myötävaikuttaa osallistumiseen ja sitä kautta parantaa ihmisen hyvinvointia, sillä tutkimukset toivat esille mielekkään toiminnan merkityksen. Ihmisen oma subjektiivinen kokemus toiminnasta on ratkaisevan tärkeää terveyden ja hyvinvoinnin kannalta. Mikään interventio, jota henkilö ei koe mielekkäänä, ei hyödytä kyseistä henkilöä, vaan ihmisen on oltava kiinnostunut siitä mitä tekee. Toimintaterapiainterventioiden koettiin parantavan elämänlaatua ja lisäävän tyytyväisyyttä elämään. Erityisesti merkityksellinen toiminta ja sosiaalinen tuki vaikuttavat tyytyväisyyden lisääntymiseen. Tarvitaan kuitenkin lisää tutkimusta esimerkiksi muiden kuin veteraanien PTSD-oireisten henkilöiden toimintaterapiainterventioiden hyödyistä

Inhibition of Excessive Oxidative Protein Folding Is Protective in MPP+ Toxicity-Induced Parkinson's Disease Models

Aims: Protein misfolding occurs in neurodegenerative diseases, including Parkinson's disease (PD). In endoplasmic reticulum (ER), an overload of misfolded proteins, particularly alpha-synuclein (alpha Syn) in PD, may cause stress and activate the unfolded protein response (UPR). This UPR includes activation of chaperones, such as protein disulphide isomerase (PDI), which assists refolding and contributes to removal of unfolded proteins. Although up-regulation of PDI is considered a protective response, its activation is coupled with increased activity of ER oxidoreductin 1 (Ero1), producing harmful hydroperoxide. The objective of this study was to assess whether inhibition of excessive oxidative folding protects against neuronal death in well-established 1-methyl-4-phenylpyridinium (MPP+) models of PD. Results: We found that the MPP+ neurotoxicity and accumulation of aSyn in the ER are prevented by inhibition of PDI or Ero1 alpha. The MPP+ neurotoxicity was associated with a reductive shift in the ER, an increase in the reduced form of PDI, an increase in intracellular Ca2+, and an increase in Ca2+-sensitive calpain activity. All these MPP+-induced changes were abolished by inhibiting PDI. Importantly, inhibition of PDI resulted in increased autophagy, and it prevented MPP+-induced death of dopaminergic neurons in Caenorhabditis elegans. Innovation and Conclusion: Our data indicate that although inhibition of PDI suppresses excessive protein folding and ER stress, it induces clearance of aggregated aSyn by autophagy as an alternative degradation pathway. These findings suggest a novel model explaining the contribution of ER dysfunction to MPP+-induced neurodegeneration and highlight PDI inhibitors as potential treatment in diseases involving protein misfolding