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Full-Text Articles in Animal Diseases

Gene Co-Expression Network Analysis Of Trypanosoma Brucei In Tsetse Fly Vector, Kennedy W. Mwangi, Rosaline W. Macharia, Joel L. Bargul Dec 2021

Gene Co-Expression Network Analysis Of Trypanosoma Brucei In Tsetse Fly Vector, Kennedy W. Mwangi, Rosaline W. Macharia, Joel L. Bargul

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Background: Trypanosoma brucei species are motile protozoan parasites that are cyclically transmitted by tsetse fly (genus Glossina) causing human sleeping sickness and nagana in livestock in sub-Saharan Africa. African trypanosomes display digenetic life cycle stages in the tsetse fly vector and in their mammalian host. Experimental work on insect-stage trypanosomes is challenging because of the difficulty in setting up successful in vitro cultures. Therefore, there is limited knowledge on the trypanosome biology during its development in the tsetse fly. Consequently, this limits the development of new strategies for blocking parasite transmission in the tsetse fly. Methods: In this study, RNA-Seq …


Sodalis Glossinidius Presence In Wild Tsetse Is Only Associated With Presence Of Trypanosomes In Complex Interactions With Other Tsetse-Specific Factors 06 Biological Sciences 0604 Genetics, Manun Channumsin, Marc Ciosi, Dan Masiga, C. Michael R. Turner, Barbara K. Mable Nov 2018

Sodalis Glossinidius Presence In Wild Tsetse Is Only Associated With Presence Of Trypanosomes In Complex Interactions With Other Tsetse-Specific Factors 06 Biological Sciences 0604 Genetics, Manun Channumsin, Marc Ciosi, Dan Masiga, C. Michael R. Turner, Barbara K. Mable

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Background: Susceptibility of tsetse flies (Glossina spp.) to trypanosomes of both humans and animals has been associated with the presence of the endosymbiont Sodalis glossinidius. However, intrinsic biological characteristics of the flies and environmental factors can influence the presence of both S. glossinidius and the parasites. It thus remains unclear whether it is the S. glossinidius or other attributes of the flies that explains the apparent association. The objective of this study was to test whether the presence of Trypanosoma vivax, T. congolense and T. brucei are related to the presence of S. glossinidius in tsetse flies when other factors …


Functional Characterization And Protein-Protein Interactions Of Trypanosome Splicing Factors U2af35, U2af65 And Sf1, Martin P. Vazquez, David Mualem, Natalia Bercovich, Michael Zeev Stern, Benson Nyambega, Omer Barda, Dan Masiga, Sachin Kumar Gupta, Shulamit Michaeli, Mariano J. Levin Apr 2009

Functional Characterization And Protein-Protein Interactions Of Trypanosome Splicing Factors U2af35, U2af65 And Sf1, Martin P. Vazquez, David Mualem, Natalia Bercovich, Michael Zeev Stern, Benson Nyambega, Omer Barda, Dan Masiga, Sachin Kumar Gupta, Shulamit Michaeli, Mariano J. Levin

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Early in the assembly of the spliceosome of eukaryotes the branch-point binding protein (BBP, also called SF1) recognizes the branch point sequence, whereas the heterodimer U2AF consisting of a 65 and a 35 kDa subunit, contacts the polypyrimidine tract and the AG splice site, respectively. Herein, we identified, cloned and expressed the Trypanosoma cruzi and Trypanosoma brucei U2AF35, U2AF65 and SF1. Trypanosomatid U2AF65 strongly diverged from yeast and human homologues. On the contrary, trypanosomatid SF1 was conserved but lacked the C-terminal sequence present in the mammalian protein. Yeast two hybrid approaches were used to assess their interactions. The interaction between …


Evidence For The Involvement Of A Tsetse Midgut Lectin-Trypsin Complex In Differentiation Of Bloodstream-Form Trypanosomes, L. U. Abubakar, G. Zimba, C. Wells, F. Mulaa, E. O. Osir Jan 2003

Evidence For The Involvement Of A Tsetse Midgut Lectin-Trypsin Complex In Differentiation Of Bloodstream-Form Trypanosomes, L. U. Abubakar, G. Zimba, C. Wells, F. Mulaa, E. O. Osir

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We have previously described a bloodmeal-induced molecule (lectin-trypsin complex) from the midgut of the tsetse fly, Glossina longipennis, with both lectin and trypsin activities (Osir et al., 1995). In this paper, we report on the isolation of a similar molecule from the midguts of Glossina fuscipes fuscipes and provide direct evidence for its involvement in the development of African trypanosomes. The molecule (native Mr ∼65,700) has two non-covalently linked subunits, Mr ∼28,800 and Mr ∼35,700. The native molecule was found to be capable of inducing differentiation of bloodstream-form trypanosomes into procyclic (midgut forms) in vitro. In the assays, specific antibodies …


Isolation Of Trypanosoma Brucei From The Monitor Lizard (Varanus Niloticus) In An Endemic Focus Of Rhodesian Sleeping Sickness In Kenya, Zipporah Njagu, Steve Mihok, Elizabeth Kokwaro, Didier Verloo Mar 1999

Isolation Of Trypanosoma Brucei From The Monitor Lizard (Varanus Niloticus) In An Endemic Focus Of Rhodesian Sleeping Sickness In Kenya, Zipporah Njagu, Steve Mihok, Elizabeth Kokwaro, Didier Verloo

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Monitor lizards were sampled along the shores of Lake Victoria to detect natural infections of potentially human-infective trypanosomes. In an area with endemic rhodesian sleeping sickness, one of 19 lizards was infected (Busia, Kenya). Six of ten lizards also showed indirect evidence of infection with Trypanosoma brucei (antibody ELISA). In an area with no recent history of human disease (Rusinga Island), no parasites were found and no antibodies to T. brucei were detected. The isolate was identified as T. brucei through xenodiagnosis (completion of the life cycle in the salivary glands of tsetse), and through molecular techniques (positive reactions with …


Isolation Of Trypanosoma Spp. From Wild Tsetse Flies Through Procyclic Expansion In Glossina Morsitans Centralis, Steve Mihok, Eli N. Munyoki, Freddie Masaninga, Paul N. Ndegwa, Reardon O. Olubayo Jan 1994

Isolation Of Trypanosoma Spp. From Wild Tsetse Flies Through Procyclic Expansion In Glossina Morsitans Centralis, Steve Mihok, Eli N. Munyoki, Freddie Masaninga, Paul N. Ndegwa, Reardon O. Olubayo

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Procyclic trypanosomes from wild tsetse flies were membrane-fed to Glossina morsitans centralis in order to develop an optimal technique for propagating field isolates. A 70% success rate was achieved in isolating Trypanosoma simiae and a variety of genotypes of T. congolense originating from G. pallidipes, G. brevipalpis and G. swynnertoni. Parasites matured into forms infective for mammals, and could be maintained by passage of gut forms to new groups of flies. In experiments with laboratory stocks, we also passaged immature gut infections of T. congolense and T. brucei from various tsetse species to G. m. centralis. The optimal technique was …


Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi Jan 1992

Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi

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Teneral Glossina morsitans centralis, G. m. morsitans and G. pallidipes were infected with three different clones of Trypanosoma brucei in blood containing d(+)-glucosamine, an inhibitor of tsetse midgut lectin. On average, 5 days of d(+)-glucosamine treatment tripled infection rates, without affecting the proportion of infections that matured. Total infection rates were equal in males and females, but twice as many infections matured in males. Counts of parasites in the guts and salivary glands of 277 flies revealed order of magnitude differences among flies, with females consistently having 2-3-times as many parasites as males. Parasite numbers varied in a sex-specific manner …