Fig 1.
A phylogeny-based classification of the genus Leishmania.
L. tarentolae belongs to the subgenus of Sauroleishmania, which is made up of mostly lizard-infecting parasites. Adapted from [1].
Fig 2.
Simplified life cycle of L. tarentolae (Sauroleishmania).
Sand fly (Sergentomyia) takes a blood meal from a gecko and thereby ingests promastigotes (major form) and some amastigotes/amastigote-like cells (minor form) of L. tarentolae. Inside the gut of the sand fly, immune cells burst, and the phagocytized part of Leishmania is released. Promastigotes colonize the lumen of the cloaca, the intestine (hindgut), and rarely, the blood of the sand fly. Although not known, it is possible that promastigotes (and amastigotes) of L. tarentolae undergo several transformations inside the sand fly, with stages of procyclic, nectomonad, leptomonad, haptomonad, and subsequently, metacyclic promastigotes (stages adapted from [80]). Metacyclic promastigotes would be the gecko-infective stage, and they are transferred back to a gecko during a new blood meal. Inside the gecko, promastigotes mainly live free in the blood. A small part is probably phagocytized by immune cells (monocytes and macrophages). Phagocytosed promastigotes might change back into amastigotes/amastigote-like cells, and the life cycle repeats. Immune cells are represented in blue, and erythrocytes are represented in red.
Fig 3.
Biotechnological applications of the eukaryotic parasite L. tarentolae.
L. tarentolae is used to study RNA editing (A), gene amplification (B), vaccine development against human-pathogenic Leishmania species (C), and recombinant (human) protein production (D). AMP, Adenosine monophosphate; ATP, Adenosine triphosphate; CHO, Chinese hamster ovary; PPi, diphosphate; REL, RNA editing ligase; REN, RNA editing endonuclease; RET, RNA editing TUTase; REX, RNA editing exonuclease; scFv, single-chain fragment variable; scFv-Fc, single-chain fragment variable fragment crystallizable; UMP, uracil monophosphate; UTP, uracil triphosphate. Partial pictures adapted from [6] for (A), [118] for (B), and [103] for (C).
Fig 4.
Microscopy images of L. tarentolae.
(A) Fluorescent L. tarentolae promastigotes expressing eGFP. (B) L. tarentolae promastigotes stained with DAPI, highlighting the nucleus (1) and the kDNA (2). (C) TEM (two fused images) of an L. tarentolae promastigote, longitudinal cell section, with a magnification of ×2,950. Cell nucleus (1), kinetoplast inside single mitochondrion (2), flagellum within flagellar pocket (3), Golgi apparatus (4), rough endoplasmic reticulum (5), glycosome (6), and acidocalcisome (7). eGFP, enhanced green fluorescent protein; kDNA, kinetoplastid DNA; TEM, transmission electron microscopy.