Abstract
Protozoan parasites of the genus Leishmania are responsible for leishmaniases, one of the most important anthropozoonotic diseases affecting millions of people worldwide. To date, there are no approved vaccines against leishmaniases for humans. At present, available treatment options lack specificity, which may lead to drug resistance and often cause adverse effects. Genomic analysis of Leishmania spp. revealed that most of the annotated genes encode hypothetical proteins, yet the functions of those proteins are still unknown. Characterization of these proteins is, hence, of utmost importance for the discovery of new therapeutic targets against leishmaniases. Reporter gene systems, or reporters, are powerful tools that enable the detection and measurement of targeted gene expression when introduced to a biological system. Over the years, numerous expression systems containing various reporters have been employed in characterizing several novel genes essential for parasite development. Such systems can be used to predict the subcellular localization of targeted proteins, screen antileishmanial drugs, and monitor the progression of infection within the vector and vertebrate hosts, among other uses. Therefore, it is critical to comprehend the available reporter gene expression systems to choose the most suitable for each study.