Mutational analysis of the phosphorylation sites of the Leishmania mexicana kinesin homologue LmxKin29

Abstract

Abstract Kinesins are motor proteins, have been identified in a wide diversity of eukaryotes, from protists to mammals. The kinetoplastids’ genome sequences have also shown the presence of a large number of kinesins. The current study presents characterise a novel L.mexicana kinesin LmxM29.3.050, thought to be associated with flagellum formation. It was found express in both the amastigote and promastigote life stages. In this study we assigned this protein as a kinesin homologue to the unknown or orphan kinesins superfamily (1). The biochemical analysis showed the MAP kinase homologue LmxMPK3 can phosphorylate full length of LmxKin29 at serine 554. Localisation studies using GFP-tagged LmxKin29 revealed that it is predominantly found in between the nucleus and the flagellar pocket, while in dividing cells LmxKin29 was found at the anterior and posterior ends of the cells. Hence, LmxKin29 might play a role in cytokinesis. Double allele deletion was successfully generated. Morphological analysis of promastigotes with LmxKin29 tagged with GFP displayed no obvious phenotypic differences comparing the mutants with wild type cells.