Flagellar elongation induced by glucose limitation is preadaptive forTrypanosoma cruzi differentiation

Abstract

Trypanosomes must sense and respond to environmental change in order to progress through their life cycles. The American trypanosome, Trypanosoma cruzi, differentiates from the noninfective epimastigote form to the infective metacyclic form spontaneously in axenic culture. Here, we investigate the initial stimulus for that change and demonstrate that T. cruzi epimastigotes sense limitation of glucose in the medium and respond by undergoing significant morphological and biochemical change. As part of this change, the mean flagellar length of the population triples, which is correlated with an increased ability to maintain interactions with hydrophobic substrates, a requirement for differentiation to the next life cycle stage. Cell Motil. Cytoskeleton 46:269–278, 2000. © 2000 Wiley‐Liss, Inc.

Morphological comparison of axenic amastigogenesis of trypomastigotes and metacyclic forms of Trypanosoma cruzi

“…Assays to examine whether the product release from the parasite during pre-incubation phase, are involved in the inhibition of the morphological transformation are in progress and might be useful to explain why the metacyclic trypomastigote can also escape from endocytic vacuole into the host cell cytoplasm (Dvorak 1975). Tyler and Engman (2000) have shown that the depletion of glucose from the medium triggers elongation of the epimastigotes flagellum. Later, the authors proposed that the intracellular glucose concentration is the key factor for both elongation of the flagellum and sustaining the differentiation of the metacyclic trypomastigote (Tyler & Engman 2001).…”

Bleach-tolerant Bacterial Species Isolated from Potable Water in Hong Kong

“…Similarly, other authors reported that epimastigotes incubated in saline solution did not complete the differentiation process, which was interrupted in the same intermediate stage [5]. Parasite IF were also described in cultures under the same conditions in which metacyclogenesis is induced, such as nutrient limitation [13], triatomine blood ingestion [19], presence of triatomine urine [5], modification of epimastigotes culture medium [6] and epimastigotes culture aging [7]. Disregarding the method of IF generation, they share the morphological characteristics here described; i.e.…”

“…The assay was performed as described by Tyler and Engman [13] with some modifications. Microscope slides precoated with amino-alkyl silane were used as hydrophobic surface.…”

“…As hydrophobic surface, slides pre-coated with silane were used, as described by Tyler and Engman [13]. Epimastigotes and IF were allowed to interact to hydrophobic surface for 10 min and then the slides were washed and Giemsa-stained for better viewing.…”

“…The flagellar elongation is considered an adaptation of this parasite on adverse conditions, such as nutrient deprivation [13]. As shown in the right panels of Figure 2, IF attached to hydrophobic surfaces had elongated flagella, when compared to epimastigotes.…”