Expression profiling by whole-genome interspecies microarray hybridization reveals differential gene expression in procyclic promastigotes, lesion-derived amastigotes, and axenic amastigotes in Leishmania mexicana

Analysis of the Leishmania donovani transcriptome reveals an ordered progression of transient and permanent changes in gene expression during differentiation

“…Nevertheless, these studies revealed more differentially expressed genes than some previous microarray studies comparing Leishmania promastigotes and amastigotes, which reported only about 1-3% of the genes undergoing differential regulation in L. major [40] or L. mexicana [44], although another report claimed ∼35% of the genes surveyed showed differential expression between Leishmania promastigotes and amastigotes [41]. In this study, we find that ∼3% of the genes surveyed appeared to be up-regulated in amastigotes, relative to promastigotes, 2.5% are down-regulated, and ∼3.5% underwent transient changes during differentiation.…”

“…In other organisms, DNA microarray analysis has become a popular and powerful method for examining changes in gene expression during differentiation and/or adaptation to new growth conditions [52][53][54][55][56][57]. While this approach has been used previously to compare the different lifecycle stages (procyclics, metacyclics and amastigotes) of L. major [39][40][41], L. donovani [42], L. infantum [43], and L. mexicana [44], the work presented in this paper represents the first genome-wide analysis of changes in gene expression during the transition from promastigotes to amastigotes, a process which was impossible to follow until host-free differentiation systems had been developed. These experiments, especially the short time points, would be impossible to carry out using animal-derived parasites, and very difficult even using in vitro macrophage cultures.…”

“…This discrepancy may reflect a species-specific difference in SHERP expression or it may represent a difference between the axenic amastigotes used in our study and the lesion-derived amastigotes used by others. The L. mexicana study [44] found a number of differences in gene expression between lesionderived and axenic amastigotes.…”

“…Microarray expression profiling has been previously used to compare procyclics, metacyclics and amastigotes of L. major [39][40][41], L. donovani [42], L. infantum [43] and L. mexicana [44], but none of these studies examined changes in gene expression during the process of differentiation. The results of the present study indicate that there is an ordered progression of specific changes in gene expression during L. donovani promastigotetoamastigote differentiation, with some genes changing expression within 5 hr after exposure to the differentiation signal, and others changing only after 24 hours.…”

Vaccines for Leishmaniasis: From proteome to vaccine candidates

“…This bias has been predicted to affect translation efficiency. 38 Thus, in the absence of proteomic evidence for a particular protein or classes of proteins (e.g., most membrane proteins) biased codon usage in the respective gene combined with mRNA abundance data from transcriptome analyses 39,40 may serve as a surrogate measure for relative protein abundance.…”