Comparative Genomics of Trypanosomatid Parasitic Protozoa

Abstract

A comparison of gene content and genome architecture of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, three related pathogens with different life cycles and disease pathology, revealed a conserved core proteome of about 6200 genes in large syntenic polycistronic gene clusters. Many species-specific genes, especially large surface antigen families, occur at nonsyntenic chromosome-internal and subtelomeric regions. Retroelements, structural RNAs, and gene family expansion are often associated with syntenic discontinuities that-along with gene divergence, acquisition and loss, and rearrangement within the syntenic regions-have shaped the genomes of each parasite. Contrary to recent reports, our analyses reveal no evidence that these species are descended from an ancestor that contained a photosynthetic endosymbiont.

Regulatory elements involved in the post-transcriptional control of stage-specific gene expression in Trypanosoma cruzi: a review

“…Ultimately, 41 chromosomes were assembled, which is well above the predicted number of T. cruzi chromosomes based on the early studies of pulsed-field gel electrophoresis analyses (Cano et al 1995, Vargas et al 2004. Although separated by hundreds of millions of years of evolution, genome organisation in T. cruzi is largely syntenic with the other two trypanosomatid genomes, collectively known as the Tri-Tryp genomes (T. brucei and L. major), and most of the species-specific genes, such as large surface protein gene families, occur at non-syntenic chromosome-internal and subtelomeric regions (El-Sayed et al 2005b).…”

“…Heterogeneous arrays as large as 600 kb for genes that encode surface proteins were found to be clustered in the T. cruzi genome (El-Sayed et al 2005b). In addition, long terminal repeat (LTR) and non-LTR retro-elements as well as other subtelomeric repeats accounted for the large proportion of repetitive sequences (50%) in this genome.…”

“…Other large gene families include the previously described retrotransposon hot spot and dispersed gene family protein-1 families that encode for proteins with unknown functions and are found mostly at subtelomeric regions, similar to the TS genes. The T. cruzi genome also contains large gene families that encode glycosyltransferases, protein kinases, protein phosphatases, kinesins, amino acid transporters and helicases as well as several gene families that encode for hypothetical proteins (El-Sayed et al 2005b). In addition to the evasion of the host immune system, the existence of highly repetitive genes in the T. cruzi genome may also serve to increase gene expression levels in the absence of strong promoters.…”

Comparative codon and amino acid composition analysis of Tritryps‐conspicuous features of Leishmania major

“…L. major, T. brucei and T. cruzi contain about 32.8, 26 and 55-megabase size haploid genomes distributed in 36, 11 and 28 chromosomes with an average GC-content of 59.7%, 46.4% and 51%, respectively. Comparative analyses [1] revealed that the three genomes share 6158 ortholog clusters of protein-coding genes, which exist in large syntenic blocks containing 80% of the T. brucei and 93% of the L. major genes. They also share a number of molecular and biochemical characters [7].…”

Detección de blancos moleculares en la ruta de señalización del fosfatidilinositol en Leishmania spp. a través de herramientas bioinformáticas y de modelado matemático

“…Una de las estrategias desarrolladas para la bús-queda de nuevos medicamentos consiste en el modelado o reconstrucción de vías metabólicas importantes que faciliten análisis bioquímicos detallados en el organismo de interés, permitiendo así la identificación de posibles blancos moleculares específicos para estos medicamentos (2)(3)(4). Los resultados obtenidos en los últimos años en la exploración de la vía del metabolismo del fosfatidil-inositol la postulan como una alternativa en el desarrollo de medicamentos para diversas enfermedades, incluida la leishmaniasis (5)(6)(7)(8)(9).…”