Differential expression of meiosis and homologous recombination (HR)-related genes during the life cycle of Trypanosoma cruzi. Differential expression of meiosis and homologous recombination (HR)-related genes during the life cycle of Trypanosoma cruzi

Trypanosoma cruzi has a complex life cycle with four morphological and differential biological stages. Some authors suggest that T. cruzi follows a preponderant clonal reproduction; nevertheless, recent genomic and transcriptomic studies show an unorthodox capacity for recombination. Therefore, we decided to estimate the differential gene expression of 10 meiosis/homologous-recombination-related genes during the T. cruzi life cycle (epimastigotes, amastigotes, cell-derived trypomastigotes, and metacyclic trypomastigotes) including epimastigotes under three different types of stress (oxidative stress, pH changes, and treatment with benznidazole (drug pressure)). We designed RT-qPCR tests with novel-designed primers to estimate the differential gene expression (∆Ct and ∆∆Ct) of nine genes (SPO11, HAP2, RAD50, MRN complex, BRCA2, DMC1, MND1, RPA) and included a previously reported RAD51 test. Our results show a basal expression of all genes during the life cycle, indicating their hypothetical role in several cellular processes but with specific signatures of differential gene expression during the life cycle (HAP2, RPA, RAD50, BRCA2, MND1, DMC1) and oxidative stress (RPA, MN complex, BRCA2, MND1, RAD51). Additionally, we found that the MRN complex works independently in T. cruzi, with profiles of MRE11 and NBS1 upregulated in some stages and stressors. Recently, studies on other trypanosomatids have remarked the influence of HAP2 and RPA in recombination and hybridization. If T. cruzi uses the same repertoire of genes, our findings could suggest that metacyclic trypomastigotes may be the putative stage the parasite uses to undergo recombination. Likewise, our study shows the differential profiles of genes expressed in response to oxidative and pH stress. More studies are needed to corroborate our findings and understand the recombination mechanism in T. cruzi.