TY - JOUR
T1 - Involvement of a Leishmania thymidine kinase in flagellum formation, promastigote shape and growth as well as virulence
AU - Thiel, Meike
AU - Harder, Simone
AU - Wiese, Martin
AU - Kroemer, Manfred
AU - Bruchhaus, Iris
PY - 2008/4
Y1 - 2008/4
N2 - Leishmania promastigote cells transmitted by their insect vector get phagocytosed by macrophages and convert into the amastigote form. In a recently performed proteomic study, a thymidine kinase (TK) was found to be preferentially expressed in amastigotes. Western blot analysis showing a marked increase in TK protein synthesis during stage differentiation from promastigotes to amastigotes confirmed this result. After comparison of the amino acid sequence of Leishmania donovani and Leishmania major thymidine kinases with thymidine kinases of other organisms the Leishmania protein has to be classified as a type II TK. Therefore, in accordance with the nomenclature of other thymidine kinases we named the Leishmania enzymes LdTK1 and LmTK1, respectively. The LdTK1 is localised within the cytoplasm of promastigotes. In amastigotes, increased expression and a clustered distribution of the protein can be observed. Lmtk1 single allele gene replacement mutants have significantly elongated flagellum. In contrast, lmtk1 double allele gene replacement mutants show a remarkably reduced flagellar length, diminished overall size and a deformed body shape. In addition, they have a 12-fold reduced growth rate. For both mutant strains, macrophage infectivity is clearly reduced compared to a L. major wildtype infection.
AB - Leishmania promastigote cells transmitted by their insect vector get phagocytosed by macrophages and convert into the amastigote form. In a recently performed proteomic study, a thymidine kinase (TK) was found to be preferentially expressed in amastigotes. Western blot analysis showing a marked increase in TK protein synthesis during stage differentiation from promastigotes to amastigotes confirmed this result. After comparison of the amino acid sequence of Leishmania donovani and Leishmania major thymidine kinases with thymidine kinases of other organisms the Leishmania protein has to be classified as a type II TK. Therefore, in accordance with the nomenclature of other thymidine kinases we named the Leishmania enzymes LdTK1 and LmTK1, respectively. The LdTK1 is localised within the cytoplasm of promastigotes. In amastigotes, increased expression and a clustered distribution of the protein can be observed. Lmtk1 single allele gene replacement mutants have significantly elongated flagellum. In contrast, lmtk1 double allele gene replacement mutants show a remarkably reduced flagellar length, diminished overall size and a deformed body shape. In addition, they have a 12-fold reduced growth rate. For both mutant strains, macrophage infectivity is clearly reduced compared to a L. major wildtype infection.
KW - leishmania donovani
KW - leishmania major
KW - thymidine kinase
KW - stage differentiation
KW - gene knockout
KW - pharmacology
UR - http://dx.doi.org/10.1016/j.molbiopara.2007.12.005
U2 - 10.1016/j.molbiopara.2007.12.005
DO - 10.1016/j.molbiopara.2007.12.005
M3 - Article
SN - 0166-6851
VL - 158
SP - 152
EP - 162
JO - Molecular and Biochemical Parasitology
JF - Molecular and Biochemical Parasitology
IS - 2
ER -