Bovine Transcriptome Analysis by SAGE Technology during an Experimental Trypanosoma congolense Infection

Abstract

In central and sub-Saharan Africa, trypanosomosis is a tsetse fly-transmitted disease, which is considered as the most important impediment to livestock production in the region. However, several indigenous West African taurine breeds (Bos taurus) present remarkable tolerance to the infection. This genetic capability, named trypanotolerance, results from numerous biological mechanisms most probably under multigenic dependences, among which are control of the trypanosome infection by limitation of parasitemia and control of severe anemia due to the pathogenic effects. Today, some postgenomic biotechnologies, such as transcriptome analyses, allow characterization of the full expressed genes involved in the majority of animal diseases under genetic control. One of them is serial analysis of gene expression (SAGE) technology, which consists of the construction of mRNA transcript libraries for qualitative and quantitative analysis of the entire genes expressed or inactivated at a particular step of cellular activation. We developed four different mRNA transcript libraries from white blood cells on a N'Dama trypanotolerant animal during an experimental Trypanosoma congolense (T. congolense) infection: one before experimental infection (ND0), one at the parasitemia peak (NDm), one at the minimal packed cell volume (NDa), and the last one at the end of the experiment after normalization (NDf). Bioinformatic comparisons in bovine genomic databases allowed us to obtain more than 75,000 sequences, among which are several known genes, some others are already described as expressed sequence tags (ESTs), and the last are completely new, but probably functional in trypanotolerance. The knowledge of all identified named or unnamed genes involved in trypanotolerance characteristics will allow us to use them in a field marker-assisted selections strategy and in microarrays prediction sets for bovine trypanotolerance.

Simultaneous gene expression profiling in human macrophages infected with Leishmania major parasites using SAGE

“…This technology was successfully applied to study the transcriptome of different parasites e.g., Plasmodium falciparum [ 22 ]. Schistosoma mansoni [ 23 ] and Trypanosoma congolense [ 24 ], among others [ 21 ].…”

Effects of increased milking frequency on gene expression in the bovine mammary gland

“…For instance, the commercially available Affymetrix Bovine Genome Array has recently been applied to reproductive studies in cattle, including characterization of changes in gene expression that may be related to embryonic development [ 12 ], female fertility [ 13 ], and sperm development [ 14 ]. Likewise, SAGE has been used in multiple immunological studies of cattle to identify genes related to parasite resistance [ 15 ], antigen presentation in lymphocytes [ 16 ], and response to bovine viral diarrhea virus infection [ 17 ].…”

Study of Bovine Trypanotolerance by Whole Transcriptome Analysis

“…In brief, mRNA populations were extracted from whole blood using oligo dT beads (I‐SAGE™ Kit, Cat. No T5000‐01; Invitrogen, Carlsbad, CA) 8,9 . Short tag sequences were isolated from the 3′ end of each mRNA, and occurrences were counted according to their relative abundance in the sample source.…”

“…Recent progress in bovine genome acquisition and annotation now allow us to reconsider this disease by using transcriptomic analysis to characterize the differential expression of all expressed genes 8,9 . To this end, we have constructed 12 SAGE libraries using the mRNA of whole white blood cells of tolerant/susceptible cattle (trypanotolerant: N'Dama, Baoulé; trypanosusceptible: zebu) sampling during an experimental Trypanosoma congolense infection 8 . Comparison of libraries shows interesting variations in expression of some genes which could have a strong link with trypanotolerance.…”