Aug 2026· Acta Tropica· Vol 281, pp.
108267
· 0 citations· 47 references
Medicine
TL;DR
The peptide-supported novel and corrected protein-coding genes identified in this study represent a valuable resource for the future exploration of candidate biomarkers and may be provide the molecular targets for improved diagnosis, prognosis, and therapeutic intervention in American tegumentary leishmaniasis.
Abstract
Leishmania panamensis, a protozoan parasite of the Viannia subgenus, causes American tegumentary leishmaniasis (ATL) throughout Central and South America, with clinical manifestations ranging from cutaneous lesions to mucosal involvement. Despite the availability of a reference genome for L. panamensis MHOM/COL/81/L13 strain, comprising 30.69 megabases across 35 chromosomes and 8,665 predicted protein-coding genes, comprehensive proteogenomic analyses to refine these annotations have remained limited. This study utilised a proteogenomic approach to enhance the genome annotation of the L. panamensis MHOM/COL/81/L13 strain by integrating publicly available liquid chromatography-tandem mass spectrometry data with a custom six-frame translated genome database. Through systematic peptide mapping and validation, we identified 50 novel protein-coding genes previously absent from the reference annotation and corrected 50 existing genes. The newly identified genes encode proteins containing functional domains, including thioredoxin, glucosyltransferases, and myotubularin, which likely contribute to parasite metabolism, host-pathogen interactions, and intracellular survival mechanisms. These findings substantially refine the genomic resource available for L. panamensis research and provide potential targets for diagnostic and therapeutic development. Future studies will incorporate orthogonal validation methods such as RNA-seq and Ribosome profiling to distinguish between functional genes and translational noise. The refined annotation enables more accurate functional genomic studies and enhances our understanding of the molecular basis underlying L. panamensis pathogenicity and immune evasion strategies. Moreover, the peptide-supported novel and corrected protein-coding genes identified in this study represent a valuable resource for the future exploration of candidate biomarkers and may be provide the molecular targets for improved diagnosis, prognosis, and therapeutic intervention in American tegumentary leishmaniasis.
It is demonstrated that proteogenomic integration significantly improves the accuracy of L. donovani genome annotation by resolving truncated gene models and uncovering hidden coding potential, which improve genome annotation and highlight previously unrecognised coding potential supported by peptide evidence in Leishmania donovani.
Soumi Chowdhury, Shubhankar Pawar, Karthick Vasudevan et al.· Current Microbiology· 0 citations
Leishmania tropica is an intracellular parasite belonging to the phylum Euglenozoa; it exhibits significant clinical heterogeneity and is spread by sandfly vectors through anthroponotic or zoonotic transmission. Leishmania RNA virus, a viral endosymbiont belonging to the Totiviridae family, has been reported in Old and New World isolates. In this study, we conducted a comparative de novo RNA-Seq analysis of LRV2 negative (LRV2-) and LRV2 positive (LRV2+) L. tropica isolates. Raw sequencing reads were quality-filtered, assembled, and clustered to generate unigenes, which were functionally annotated against seven comprehensive functional and taxonomic databases. In addition, differential expression and functional enrichment analyses were performed. A validation study was conducted using qRT-PCR with a 32-gene target panel across 26 strains for which LRV2 status had previously been determined. In total, approximately 10.53 Gb of sequence data were generated using the BGISEQ-500 platform. Our comparative analysis points toward a significant transcriptomic modulation that may be associated with LRV2 status, encompassing 6,774 differentially expressed genes. Functional enrichment analyses suggested alterations in the expression of genes associated with central dogma processes, the endomembrane system, cell cycle regulation, and fundamental metabolic responses. Multiple Leishmania strain sets used in qRT-PCR validation confirmed the expression patterns of key signature components potentially associated with LRV2 in the parasite system. The identified profile encompasses stress adaptation and virulence factors, as well as distinct gene modules. Overall, these findings provide a comprehensive transcriptomic resource that may guide further functional investigations into the mechanisms governing virus-parasite interactions in Old World leishmaniasis.
M. Nalçacı, Y. Özbel, Ahmet Mermer et al.· Acta Tropica· 0 citations