scholarly journals The long and winding road of reverse genetics in Trypanosoma cruzi

2021 ◽  
Vol 8 (9) ◽  
pp. 203-207
Author(s):  
Miguel A. Chiurillo ◽  
Noelia Lander
Keyword(s):  
Trypanosoma Cruzi ◽  
Trypanosoma Brucei ◽  
Reverse Genetics ◽  
Genetic Manipulation ◽  
Genetically Modify ◽  
Protozoan Parasite ◽  
Future Directions ◽  
Distinctive Features ◽  
Biologically Relevant ◽  
Leishmania Spp

Trypanosomes are early divergent protists with distinctive features among eukaryotic cells. Together with Trypanosoma brucei and Leishmania spp., Trypanosoma cruzi has been one of the most studied members of the group. This protozoan parasite is the causative agent of Chagas disease, a leading cause of heart disease in the Americas, for which there is no vaccine or satisfactory treatment available. Understanding T. cruzi biology is crucial to identify alternative targets for antiparasitic interventions. Genetic manipulation of T. cruzi has been historically challenging. However, the emergence of CRISPR/Cas9 technology has significantly improved the ability to generate genetically modified T. cruzi cell lines. Still, the system alone is not sufficient to answer all biologically relevant questions. In general, current genetic methods have limitations that should be overcome to advance in the study of this peculiar parasite. In this brief historic overview, we highlight the strengths and weaknesses of the molecular strategies that have been developed to genetically modify T. cruzi, emphasizing the future directions of the field.

The structural mechanics of cell division in Trypanosoma brucei

2008 ◽  
Vol 36 (3) ◽  
pp. 421-424 ◽  
Author(s):  
Sue Vaughan ◽  
Keith Gull
Keyword(s):  
Cell Division ◽  
Trypanosoma Brucei ◽  
Mammalian Cells ◽  
Reverse Genetics ◽  
Protozoan Parasite ◽  
Cell Types ◽  
Single Copy ◽  
Structural Mechanics ◽  
Sub Saharan Africa ◽  
Mammalian Host

Undoubtedly, there are fundamental processes driving the structural mechanics of cell division in eukaryotic organisms that have been conserved throughout evolution and are being revealed by studies on organisms such as yeast and mammalian cells. Precision of structural mechanics of cytokinesis is however probably no better illustrated than in the protozoa. A dramatic example of this is the protozoan parasite Trypanosoma brucei, a unicellular flagellated parasite that causes a devastating disease (African sleeping sickness) across Sub-Saharan Africa in both man and animals. As trypanosomes migrate between and within a mammalian host and the tsetse vector, there are periods of cell proliferation and cell differentiation involving at least five morphologically distinct cell types. Much of the existing cytoskeleton remains intact during these processes, necessitating a very precise temporal and spatial duplication and segregation of the many single-copy organelles. This structural precision is aiding progress in understanding these processes as we apply the excellent reverse genetics and post-genomic technologies available in this system. Here we outline our current understanding of some of the structural aspects of cell division in this fascinating organism.

scholarly journals Μελέτη μορίων που παίζουν σημαντικό ρόλο στην ανάπτυξη των πρωτόζωων Leishmania και Trypanosoma

2014 ◽  
Author(s):  
Αντωνία Ευσταθίου
Keyword(s):  
Trypanosoma Cruzi ◽  
Trypanosoma Brucei ◽  
Leishmania Spp

Τα πρωτόζωα Leishmania spp., Trypanosoma brucei και Trypanosoma cruzi ανήκουν στις τρυπανοσωματίδες και είναι παράσιτα που προκαλούν τις ασθένειες λεϊσμανίαση, Ανθρώπινη Αφρικανική Τρυπανοσωμίαση (ΗΑΤ) και Αμερικανική Τρυπανοσωμίαση (Νόσος του Chagas), αντίστοιχα. Αυτές οι παραμελημένες ασθένειες προκαλούν σημαντική νοσηρότητα και υψηλά ποσοστά θνησιμότητας παγκοσμίως. Μέχρι σήμερα, δεν έχουν ανακαλυφθεί αποτελεσματικά εμβόλια για τον άνθρωπο για την πρόληψη των ασθενειών αυτών, ενώ η χημειοθεραπεία είναι συχνά αναποτελεσματική ή/και τοξική και έχει υψηλό κόστος. Για το λόγο αυτό, είναι επιτακτική ανάγκη εύρεσης καινούριων και ιδανικότερα στοχευμένων χημειοθεραπειών. Παράλληλα, η αναζήτηση ιδανικών υποψήφιων παρασιτικών παραγόντων όπου η στόχευση τους να αναστέλλει επιλεκτικά τη διαφοροποίηση και ανάπτυξη των τρυπανοσωματίδων είναι μείζονος σημασίας. Τα παραπάνω αναμένεται να οδηγήσουν στον ορθολογικό σχεδιασμό καινούριων φαρμάκων. Η ολοκλήρωση της χαρτογράφησης του γονιδιώματος πολλών ειδών των τρυπανοσωματίδων μας παρέχει πλούτο γνώσης που μπορεί να χρησιμοποιηθεί για την αναγνώριση των ιδανικών στόχων και των αντίστοιχων υποψήφιων φαρμάκων. Τα φάρμακα αυτά στη συνέχεια πρέπει να επιλεχθούν έτσι ώστε να εμφανίζουν επιλεκτικότητα έναντι των παρασιτικών πρωτεϊνών αντί των πρωτεϊνών του θηλαστικού ξενιστή. Στην παρούσα διατριβή, επικεντρωθήκαμε στη μελέτη σημαντικών πρωτεϊνών των παρασίτων, και μοριακών στόχων φαρμάκων για τη θεραπεία της λεϊσμανίασης και της ΗΑΤ, που παίζουν σημαντικό ρόλο στην εξέλιξη του κυτταρικού κύκλου και στη βιωσιμότητα του παρασίτου. Πιο συγκεκριμένα, επικεντρωθήκαμε στην μελέτη της κινάσης της συνθετάσης του γλυκογόνου 3 (GSK-3) και της cdc2-σχετιζόμενης κινάσης 3 (CRK3). Μια βιβλιοθήκη χημικών αναστολέων που απαρτίζεται από ανάλογα ιντιρουμπίνης (μια δις-ινδόλη που απαντάται σε μαλάκια και φυτά), τα οποία στοχεύουν τις αντίστοιχες κινάσες των θηλαστικών δρώντας ως ATP-ανταγωνιστικοί αναστολείς, βρέθηκε να έχουν ισχυρή αντιπαρασιτική δράση. Ο τρόπος δράσης των αναλόγων αυτών υποδηλώνει σημαντικές διαφορές στο ενεργό κέντρο της κινάσης GSK-3 των παρασίτων Leishmania και Τ. brucei, αλλά και σε σχέση με την ομόλογη ανθρώπινη GSK-3. Ταυτόχρονα, οι αναστολείς αυτοί δοκιμάστηκαν για την δράση τους έναντι των παρασίτων Τ. cruzi τόσο in vitro όσο και in vivo. Τέλος, ένας αναστολέας βρέθηκε να είναι πολλά υποσχόμενος έναντι της νόσου του Chagas σε ποντικούς Balb/c ενώ δύο αναστολείς της λεϊσμανιακής GSK-3 βρέθηκαν να έχουν υποσχόμενη δραστικότητα στην οξεία και στη χρόνια φάση της σπλαχνικής λεϊσμανίασης σε πειραματικό μοντέλο ποντικού Balb/C. Η περαιτέρω μελέτη της in vivo δράσης των αναστολέων αυτών μπορεί να βοηθήσει στην διαλεύκανση του μηχανισμού δράσης των αναστολέων της GKS-3 ή/και να χρησιμεύσει στην ανάπτυξη μιας συνδυαστικής θεραπείας εναντίον της λεϊσμανίασης και της αμερικάνικής τρυπανοσωμίασης. Συνοπτικά, τα αποτελέσματα που περιγράφονται παραπάνω συμβάλλουν στην ανάπτυξη ανακάλυψης στοχευμένων φαρμάκων έναντι των παρασιτικών κινασών για τη θεραπεία της λεϊσμανίασης, της ΗΑΤ και της νόσου του Chagas.

scholarly journals Application of CRISPR/Cas9-Based Reverse Genetics in Leishmania braziliensis: Conserved Roles for HSP100 and HSP23

Genes ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1159
Author(s):  
Vanessa Adaui ◽  
Constanze Kröber-Boncardo ◽  
Christine Brinker ◽  
Henner Zirpel ◽  
Julie Sellau ◽  
...  
Keyword(s):  
New World ◽  
Reverse Genetics ◽  
Leishmania Major ◽  
Genetic Manipulation ◽  
Protozoan Parasite ◽  
Single Copy ◽  
Leishmania Braziliensis ◽  
Old World ◽  
Tegumentary Leishmaniasis ◽  
Null Mutants

The protozoan parasite Leishmania (Viannia) braziliensis (L. braziliensis) is the main cause of human tegumentary leishmaniasis in the New World, a disease affecting the skin and/or mucosal tissues. Despite its importance, the study of the unique biology of L. braziliensis through reverse genetics analyses has so far lagged behind in comparison with Old World Leishmania spp. In this study, we successfully applied a cloning-free, PCR-based CRISPR–Cas9 technology in L. braziliensis that was previously developed for Old World Leishmania major and New World L. mexicana species. As proof of principle, we demonstrate the targeted replacement of a transgene (eGFP) and two L. braziliensis single-copy genes (HSP23 and HSP100). We obtained homozygous Cas9-free HSP23- and HSP100-null mutants in L. braziliensis that matched the phenotypes reported previously for the respective L. donovani null mutants. The function of HSP23 is indeed conserved throughout the Trypanosomatida as L. majorHSP23 null mutants could be complemented phenotypically with transgenes from a range of trypanosomatids. In summary, the feasibility of genetic manipulation of L. braziliensis by CRISPR–Cas9-mediated gene editing sets the stage for testing the role of specific genes in that parasite’s biology, including functional studies of virulence factors in relevant animal models to reveal novel therapeutic targets to combat American tegumentary leishmaniasis.

Basic Biology of Trypanosoma Cruzi

2020 ◽  
Vol 26 ◽  
Author(s):  
Aline Araujo Zuma ◽  
Emile dos Santos Barrias ◽  
Wanderley de Souza
Keyword(s):  
Trypanosoma Cruzi ◽  
Trypanosoma Brucei ◽  
Cell Biology ◽  
Structural Organization ◽  
Developmental Stages ◽  
Endocytic Pathway ◽  
Host Cells ◽  
Cellular Organization ◽  
Basic Biology ◽  
Comparative Information

Abstract:: The present review addresses basic aspects of the biology of the pathogenic protozoa Trypanosoma cruzi and some comparative information with Trypanosoma brucei. Like eukaryotic cells, their cellular organization is similar to that of mammalian hosts. However, these parasites present structural particularities. That is why the following topics are emphasized in this paper: developmental stages of the life cycle in the vertebrate and invertebrate hosts; the cytoskeleton of the protozoa, especially the sub-pellicular microtubules; the flagellum and its attachment to the protozoan body through specialized junctions; the kinetoplast-mitochondrion complex, including its structural organization and DNA replication; the glycosome and its role in the metabolism of the cell; the acidocalcisome, describing its morphology, biochemistry, and functional role; the cytostome and the endocytic pathway; the organization of the endoplasmic reticulum and Golgi complex; the nucleus, describing its structural organization during interphase and division; and the process of interaction of the parasite with host cells. The unique characteristics of these structures also make them interesting chemotherapeutic targets. Therefore, further understanding of cell biology aspects contributes to the development of drugs for chemotherapy.

The Widespread Anti-Protozoal Action of HIV Aspartic Peptidase Inhibitors: Focus on Plasmodium spp., Leishmania spp. and Trypanosoma cruzi

2017 ◽  
Vol 17 (11) ◽  
pp. 1303-1317 ◽  
Author(s):  
Marta Branquinha ◽  
Leandro Sangenito ◽  
Catia Sodre ◽  
Lucimar Kneipp ◽  
Claudia d'Avila-Levy ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Peptidase Inhibitors ◽  
Aspartic Peptidase ◽  
Leishmania Spp

scholarly journals Metabolic reprogramming during the Trypanosoma brucei life cycle

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 683 ◽  
Author(s):  
Terry K. Smith ◽  
Frédéric Bringaud ◽  
Derek P. Nolan ◽  
Luisa M. Figueiredo
Keyword(s):  
Life Cycle ◽  
Trypanosoma Brucei ◽  
Model Organism ◽  
Protozoan Parasite ◽  
Tsetse Fly ◽  
Metabolic Reprogramming ◽  
Mammalian Host ◽  
Insect Vector ◽  
Environmental Signals ◽  
Cellular Metabolic Activity

Cellular metabolic activity is a highly complex, dynamic, regulated process that is influenced by numerous factors, including extracellular environmental signals, nutrient availability and the physiological and developmental status of the cell. The causative agent of sleeping sickness, Trypanosoma brucei, is an exclusively extracellular protozoan parasite that encounters very different extracellular environments during its life cycle within the mammalian host and tsetse fly insect vector. In order to meet these challenges, there are significant alterations in the major energetic and metabolic pathways of these highly adaptable parasites. This review highlights some of these metabolic changes in this early divergent eukaryotic model organism.

scholarly journals Polo-like kinase is required for Golgi and bilobe biogenesis in Trypanosoma brucei

2008 ◽  
Vol 181 (3) ◽  
pp. 431-438 ◽  
Author(s):  
Christopher L. de Graffenried ◽  
Helen H. Ho ◽  
Graham Warren
Keyword(s):  
Cell Cycle ◽  
Endoplasmic Reticulum ◽  
Trypanosoma Brucei ◽  
Protozoan Parasite ◽  
Controlled Assembly

A bilobed structure marked by TbCentrin2 regulates Golgi duplication in the protozoan parasite Trypanosoma brucei. This structure must itself duplicate during the cell cycle for Golgi inheritance to proceed normally. We show here that duplication of the bilobed structure is dependent on the single polo-like kinase (PLK) homologue in T. brucei (TbPLK). Depletion of TbPLK leads to malformed bilobed structures, which is consistent with an inhibition of duplication and an increase in the number of dispersed Golgi structures with associated endoplasmic reticulum exit sites. These data suggest that the bilobe may act as a scaffold for the controlled assembly of the duplicating Golgi.

Sign in / Sign up

Export Citation Format

Share Document