9 research outputs found
A long noncoding RNA promotes parasite differentiation in African trypanosomes
Copyright © 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC)The parasite Trypanosoma brucei causes African sleeping sickness that is fatal to patients if untreated. Parasite differentiation from a replicative slender form into a quiescent stumpy form promotes host survival and parasite transmission. Long noncoding RNAs (lncRNAs) are known to regulate cell differentiation in other eukaryotes. To determine whether lncRNAs are also involved in parasite differentiation, we used RNA sequencing to survey the T. brucei genome, identifying 1428 previously uncharacterized lncRNA genes. We find that grumpy lncRNA is a key regulator that promotes parasite differentiation into the quiescent stumpy form. This function is promoted by a small nucleolar RNA encoded within the grumpy lncRNA. snoGRUMPY binds to messenger RNAs of at least two stumpy regulatory genes, promoting their expression. grumpy overexpression reduces parasitemia in infected mice. Our analyses suggest that T. brucei lncRNAs modulate parasite-host interactions and provide a mechanism by which grumpy regulates cell differentiation in trypanosomes.This work was supported in part by Fundação para a Ciência e Tecnologia (FCT) grant, awarded to F.G. and entitled “Long noncoding RNAs as new diagnostic biomarkers for African Sleeping sickness” (PTDC/DTPEPI/7099/2014, start date: 1 January 2016, end date: 31 December 2018); also by Howard Hughes Medical Institute International Early Career Scientist Program (project title: “How parasites use epigenetics to evade host defenses,” project no. 55007419, start date: 1 February 2012, end date: 31 January 2017); and by the European Research Council (project title: “Exploring the hidden life of African trypanosomes: parasite fat tropism and implications for the disease,” project no. 771714, start date: 1 August 2018, end date: 31 January 2024), both awarded to L.M.F. The project leading to these results have received funding from “la Caixa” Foundation under the agreement LCF/PR/HR20/52400019 [project title: “Mechanism and function of epitranscriptomic poly(A) tail modifications in African trypanosomes,” project no. HR20-00361, start date: 1 March 2021, end date: 29 February 2024]. L.M.F. is supported by FCT (IF/01050/2014, project title: “Molecular basis for the efficient biology of trypanossome parasitism,” start date: 1 January 2015, end date: 31 December 2019) and by CEEC institutional program (CEECINST/00110/2018, start date: 1 January 2020, end date: 14 December 2020). C.N. acknowledges the support of the Spanish Ministry of Economy, Industry and Competitiveness (MEIC) to the EMBL partnership, the Centro de Excelencia Severo Ochoa and the CERCA Programme/Generalitat de Catalunya. S. Michaeli acknowledges the support of the Israel Science Foundation (ref. 1959/20) from October 2020 to October 2025, entitled “Functional analysis of rRNA processing and the role of rRNA modification for specialized translation in the two life stages of trypanosomes” and U.S. Binational Science Foundation (ref. 2015/219) from October 2015 to October 2019, entitled “The role and mechanism of RNA pseudo-uridylation and sugar methylation (Nm) during the developmental cycle of trypanosomes.” The work done in A.D.’s laboratory was supported by National Science Center SONATA BIS grant, entitled “Non-canonical RNA tailing and other post-transcriptional regulatory mechanisms in T cell-mediated adaptive immunity” (proposal ID: 492777, agreement no: UMO-2020/38/E/NZ2/00372, start date: 22 March 2021, end date: 21 March 2026); National Science Center OPUS grant, entitled “Analysis of the role of cytoplasmic polyadenylation in the regulation of the innate immune response” (proposal ID: 443521, agreement no.: UMO-2019/33/B/NZ2/01773, start date: 2 March 2020, end date: 1 March 2023); and European Union’s Horizon 2020 (H2020-WIDESPREAD-03-2017)–ERAChair, entitled “MOlecular Signaling in Health and Disease - Interdisciplinary Centre of Excellence” (acronym: MOSaIC, agreement no.: 810425, implementation period: start date: 1 November 2018, end date: 31 October 2023).info:eu-repo/semantics/publishedVersio
People with Autism in Society – Challenge of 21th Century. Case of Poland
AbstractThe below article concerns important social issues. If a social exclusion is becoming a less crucial problem nowadays the general social awareness still does not show the full acceptation of autistic people as members of a society with full rights. A triple aspect of the frame of the reference – pedagogical, legal and sociological shows the interdisciplinary approach of this article. This thesis was completed on the basis of the newest research and the newest available literature
Order of removal of conventional and nonconventional introns from nuclear transcripts of Euglena gracilis.
Nuclear genes of euglenids and marine diplonemids harbor atypical, nonconventional introns which are not observed in the genomes of other eukaryotes. Nonconventional introns do not have the conserved borders characteristic for spliceosomal introns or the sequence complementary to U1 snRNA at the 5' end. They form a stable secondary structure bringing together both exon/intron junctions, nevertheless, this conformation does not resemble the form of self-splicing or tRNA introns. In the genes studied so far, frequent nonconventional introns insertions at new positions have been observed, whereas conventional introns have been either found at the conserved positions, or simply lost. In this work, we examined the order of intron removal from Euglena gracilis transcripts of the tubA and gapC genes, which contain two types of introns: nonconventional and spliceosomal. The relative order of intron excision was compared for pairs of introns belonging to different types. Furthermore, intermediate products of splicing were analyzed using the PacBio Next Generation Sequencing system. The analysis led to the main conclusion that nonconventional introns are removed in a rapid way but later than spliceosomal introns. Moreover, the observed accumulation of transcripts with conventional introns removed and nonconventional present may suggest the existence of a time gap between the two types of splicing
Intermediate introns in nuclear genes of euglenids – are they a distinct type?
Background
Nuclear genes of euglenids contain two major types of introns: conventional spliceosomal and nonconventional introns. The latter are characterized by variable non-canonical borders, RNA secondary structure that brings intron ends together, and an unknown mechanism of removal. Some researchers also distinguish intermediate introns, which combine features of both types. They form a stable RNA secondary structure and are classified into two subtypes depending on whether they contain one (intermediate/nonconventional subtype) or both (conventional/intermediate subtype) canonical spliceosomal borders. However, it has been also postulated that most introns classified as intermediate could simply be special cases of conventional or nonconventional introns.
Results
Sequences of tubB, hsp90 and gapC genes from six strains of Euglena agilis were obtained. They contain four, six, and two or three introns, respectively (the third intron in the gapC gene is unique for just one strain). Conventional introns were present at three positions: two in the tubB gene (at one position conventional/intermediate introns were also found) and one in the gapC gene. Nonconventional introns are present at ten positions: two in the tubB gene (at one position intermediate/nonconventional introns were also found), six in hsp90 (at four positions intermediate/nonconventional introns were also found), and two in the gapC gene.
Conclusions
Sequence and RNA secondary structure analyses of nonconventional introns confirmed that their most strongly conserved elements are base pairing nucleotides at positions +4, +5 and +6/ -8, −7 and −6 (in most introns CAG/CTG nucleotides were observed). It was also confirmed that the presence of the 5' GT/C end in intermediate/nonconventional introns is not the result of kinship with conventional introns, but is due to evolutionary pressure to preserve the purine at the 5' end. However, an example of a nonconventional intron with GC-AG ends was shown, suggesting the possibility of intron type conversion between nonconventional and conventional. Furthermore, an analysis of conventional introns revealed that the ability to form a stable RNA secondary structure by some introns is probably not a result of their relationship with nonconventional introns. It was also shown that acquisition of new nonconventional introns is an ongoing process and can be observed at the level of a single species. In the recently acquired intron in the gapC gene an extended direct repeats at the intron-exon junctions are present, suggesting that double-strand break repair process could be the source of new nonconventional introns.Science, Faculty ofNon UBCBotany, Department ofReviewedFacult
Periodontitis-Related Knowledge and Its Relationship with Oral Health Behavior among Adult Patients Seeking Professional Periodontal Care
Background: Periodontitis is a chronic inflammatory disease that not only damages the stomatognathic system, but may also adversely influence other systems and organs. Patients with low oral health literacy levels are more prone to gingivitis/periodontitis and have a more severe disease course. Methods: A written questionnaire was carried out to assess the knowledge of patients of the Outpatient Clinic of Department of Periodontal and Oral Mucosa Diseases, Medical University of Bialystok, Poland. The questions concerned knowledge regarding the causes of periodontal disease, its risk factors, and the connection between periodontal disease and general health status. To analyze the population, patients were divided according to gender, age and if they were first-time or regular outpatients. Results: Written questionnaires were completed by a total of 302 patients. In the studied population, we noted knowledge deficits, particularly related to weaker periodontal disease risk factors (stress, diabetes, osteoporosis, obesity) and the genetic factor, which is the determinant of periodontitis. The patients’ awareness of the role of plaque bacteria and the effect of smoking on the periodontium was at a relatively high level. The respondents were also aware of the impact of periodontal disease on general health as well as the role of oral hygiene in preventing the disease. At the same time, few of them (26%) used interdental brushes or an irrigator (8%). Conclusions: We demonstrated that patients have an insufficient level of knowledge related to risk factors as well as the prevention of periodontal disease. Awareness of the extent of oral health literacy among patients will help to identify key issues connected with health education intervention
TENT5 cytoplasmic noncanonical poly(A) polymerases regulate the innate immune response in animals
International audienceInnate immunity is the first line of host defense against pathogens. Here, through global transcriptome and proteome analyses, we uncover that newly described cytoplasmic poly(A) polymerase TENT-5 (terminal nucleotidyltransferase 5) enhances the expression of secreted innate immunity effector proteins in Caenorhabditis elegans. Direct RNA sequencing revealed that multiple mRNAs with signal peptide-encoding sequences have shorter poly(A) tails in tent-5-deficient worms. Those mRNAs are translated at the endoplasmic reticulum where a fraction of TENT-5 is present, implying that they represent its direct substrates. Loss of tent-5 makes worms more susceptible to bacterial infection. Notably, the role of TENT-5 in innate immunity is evolutionarily conserved. Its orthologs, TENT5A and TENT5C, are expressed in macrophages and induced during their activation. Analysis of macrophages devoid of TENT5A/C revealed their role in the regulation of secreted proteins involved in defense response. In summary, our study reveals cytoplasmic polyadenylation to be a previously unknown component of the posttranscriptional regulation of innate immunity in animals