Right place, right time: Environmental sensing and signal transduction directs cellular differentiation and motility in Trypanosoma brucei

• Published in: Molecular microbiology 2021-05, Vol.115 (5), p.930-941
• Main Authors: Walsh, Breanna, Hill, Kent L.
• Format: Article
• Language: English
• Subjects: Animals; Cell Differentiation; development; Developmental stages; Differentiation (biology); Gene expression; Humans; Life Cycle Stages; Life cycles; Metabolism; Morphology; Motility; Parasites; Protein turnover; Protozoan Proteins - genetics; Protozoan Proteins - metabolism; sensing; Signal Transduction; Signaling; Trypanosoma brucei; Trypanosoma brucei brucei - cytology; Trypanosoma brucei brucei - genetics; Trypanosoma brucei brucei - metabolism; trypanosome; Trypanosomiasis, African - parasitology
• ISSN: 0950-382X; 1365-2958
• DOI: 10.1111/mmi.14682

Trypanosoma brucei and other African trypanosomes are vector‐borne parasites that cause substantial human suffering across sub‐Saharan Africa. The T. brucei life cycle is punctuated by numerous developmental stages, each occurring in a specific environmental niche and characterized by a unique morphology, metabolism, surface protein coat, and gene expression profile. The environmental cues and signaling pathways that drive transitions between these stages remain incompletely understood. Recent studies have started to fill this gap in knowledge. Likewise, several new studies have expanded our understanding of parasite movement through specific tissues and the parasite's ability to alter movement in response to external cues. Life cycle stage differentiation and motility are intimately integrated phenomena, as parasites must be at the right place (i.e., within a specific environmental milieu) at the right time (i.e., when they are appropriately staged and preadapted for perceiving and responding to signals) in order to complete their life cycle. In this review, we highlight some of the recent work that has transformed our understanding of signaling events that control parasite differentiation and motility. Increased knowledge of T. brucei environmental sensing and signal transduction advances our understanding of parasite biology and may direct prospective chemotherapeutic and transmission blockade strategies that are critical to eradication efforts. Trypanosoma brucei development is coordinated with movement through host tissues. T. brucei transmission and pathogenesis require the organism to sense and adapt to diverse tissue environments in the human host and tsetse fly vector. To achieve this, signals from host and parasite engage signal transduction pathways that direct parasite development and movement between tissues. This review highlights recent work that has shed light on these events.