ABSTRACT: RBP9-TAP was expressed in bloodstream T. brucei and bound mRNA was pulled down using IgG beads and eluted via TEV-protease cleavage. rRNA was depleted using RNAseH and rRNA hybridizing oligos.
Project description:Gradient fractions of RNAi of XAC1 (Tb927.7.2780) in Trypanosoma brucei bloodstream forms. RNAi was induced using tetracycline and cell extracts were fractionated into polysomal and monosome-non-ribosome-associated fractions.
Project description:Bloodstream-form trypanosomes (Lister 427) constitutively expressing ZC3H5-TAP (Tb927.3.740) were used. The protein was pulled down with an IgG column , then the protein and bound RNA was eluted using TEV protease. RNA was then sequenced from unbound (flow-through) and bound (eluate) fractions.
Project description:Trypanosoma brucei gambiense is the causative agent of the fatal human disease African sleeping sickness. Here we have compared the transcriptome of two different life cycle stages, the potentially human-infective bloodstream form and the non-human-infective procyclic stage, using digital gene expression (DGE) analysis. Overall design: Digital gene expression analysis was performed on RNA from 3 biological replicates of bloodstream cultured T.b. gambiense strain STIB 386 and compared to that from 3 biological replicates of procyclic cultured T.b. gambiense strain STIB 386.
Project description:The host range of African trypanosomes is influenced by innate protective molecules in the blood of primates. A subfraction of human high-density lipoprotein (HDL) containing apolipoprotein A-I, apolipoprotein L-I, and haptoglobin-related protein is toxic to Trypanosoma brucei brucei but not the human sleeping sickness parasite Trypanosoma brucei rhodesiense. It is thought that T. b. rhodesiense evolved from a T. b. brucei-like ancestor and expresses a defense protein that ablates the antitrypanosomal activity of human HDL. To directly investigate this possibility, we developed an in vitro selection to generate human HDL-resistant T. b. brucei. Here we show that conversion of T. b. brucei from human HDL sensitive to resistant correlates with changes in the expression of the variant surface glycoprotein (VSG) and abolished uptake of the cytotoxic human HDLs. Complete transcriptome analysis of the HDL-susceptible and -resistant trypanosomes confirmed that VSG switching had occurred but failed to reveal the expression of other genes specifically associated with human HDL resistance, including the serum resistance-associated gene (SRA) of T. b. rhodesiense. In addition, we found that while the original active expression site was still utilized, expression of three expression site-associated genes (ESAG) was altered in the HDL-resistant trypanosomes. These findings demonstrate that resistance to human HDLs can be acquired by T. b. brucei. Keywords: Trypanosoma, VSG, antigenic switching, HDL-resistance Overall design: Bloodstream stages of the Lister strain 427 T. b. brucei (MiTat 1.2), expressing VSG221, were used in these studies. Cells were cultured in HMI-9 medium with the addition of heat inactivated fetal bovine serum (FBS) (10%) and Serum Plus (10%). T. b. brucei 427-221 is an antigenically stable line and contains a single copy of the vsg221 gene within the 221 expression site (221ES). At a cell density of approximately 1,000,000 cells/ml, T. b. brucei 427-221 were exposed to various amounts of human HDLs for 24 h in a 6 well plate. Surviving trypanosomes were counted using a hemocytometer then diluted into fresh HMI-9 medium and allowed to recover for 5-14 days. Once the cells had grown to a density of approximately 1,000,000 cells/ml, they were once again incubated with human HDLs. Each round of selection was performed with increasing concentrations of human HDLs and freezer stocks were prepared for each surviving population. Over nine months we conducted eight rounds of human HDL selection, resulting in a population of T. b. brucei that survived incubation with 800 µl of human HDLs (160 lytic U).
Project description:Cy3 and Cy5 direct labelled RNA from Bloodstream MiTat1.1 trypanosomes and Procyclic 427 Lister were hybridized onto JCVI Trypanosoma brucei oligoarrays (version2). Procyclic RNA were used as control for data analysis.
Project description:ZC3H5 was knocked down in bloodstream form T.brucei by RNAi for 0h and 12h. WT bloodstream form cells were used as control. Polysome fractionation was performed, RNA was purified from each fraction and fractions were pooled the following: F=free fraction; M=monosomes; L=light polysomes; H=heavy polysomes. RNA was depleted and RNA-Seq was performed.
Project description:A tagged ectopic version of the ELAV-like protein Tb927.8.6650 of T. brucei was expressed in stable cell lines and pulled down. Co-purifying transcripts were analyzed by sequencing to identify RNAs associated with Tb927.8.6650. Overall design: Stable procyclic form cell lines expressing tetracycline-inducible TAP-tagged Tb927.8.6650 were created. Cells were harvested 48h after tet-induction, followed by tandem affinity purification of Tb927.8.6650, extraction of co-purified RNA, and sequencing.