title: Transcriptome Profiling of Trypanosoma brucei Development in the Tsetse Fly Vector Glossina morsitans.
abstract: African trypanosomes, the causative agents of sleeping sickness in humans and nagana in animals, have a complex digenetic life cycle between a mammalian host and an insect vector, the blood-feeding tsetse fly. Although the importance of the insect vector to transmit the disease was first realized over a century ago, many aspects of trypanosome development in tsetse have not progressed beyond a morphological analysis, mainly due to considerable challenges to obtain sufficient material for molecular studies. Here, we used high-throughput RNA-Sequencing (RNA-Seq) to profile Trypanosoma brucei transcript levels in three distinct tissues of the tsetse fly, namely the midgut, proventriculus and salivary glands. Consistent with current knowledge and providing a proof of principle, transcripts coding for procyclin isoforms and several components of the cytochrome oxidase complex were highly up-regulated in the midgut transcriptome, whereas transcripts encoding metacyclic VSGs (mVSGs) and the surface coat protein brucei alanine rich protein or BARP were extremely up-regulated in the salivary gland transcriptome. Gene ontology analysis also supported the up-regulation of biological processes such as DNA metabolism and DNA replication in the proventriculus transcriptome and major changes in signal transduction and cyclic nucleotide metabolism in the salivary gland transcriptome. Our data highlight a small repertoire of expressed mVSGs and potential signaling pathways involving receptor-type adenylate cyclases and members of a surface carboxylate transporter family, called PADs (Proteins Associated with Differentiation), to cope with the changing environment, as well as RNA-binding proteins as a possible global regulators of gene expression.
authors.affiliation: Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Amy F
authors.initials: AF
authors.lastname: Savage
authors.affiliation: Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Nikolay G
authors.initials: NG
authors.lastname: Kolev
authors.affiliation: Department of Cell Biology, School of Medicine, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Franklin
authors.affiliation: Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Aurelien
authors.initials: A
authors.lastname: Vigneron
authors.affiliation: Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Serap
authors.initials: S
authors.lastname: Aksoy
authors.affiliation: Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, Connecticut, United States of America.
authors.forename: Christian
authors.initials: C
authors.lastname: Tschudi
mesh_terms: D000818:Animals; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D015723:Gene Library; D059014:High-Throughput Nucleotide Sequencing; D007303:Insect Vectors / Q000469:parasitology; D007413:Intestinal Mucosa / Q000378:metabolism; D008018:Life Cycle Stages; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D011531:Proventriculus / Q000378:metabolism; D012469:Salivary Glands / Q000378:metabolism; D017423:Sequence Analysis, RNA; D059467:Transcriptome; D014346:Trypanosoma brucei brucei / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D014370:Tsetse Flies / Q000469:parasitology*; D015854:Up-Regulation
chemical_list: D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; C053277:procyclic acidic repetitive protein, Trypanosoma; D003576:Electron Transport Complex IV