UC San Diego
Characterization of a putative novel Ras effector in Dictyostelium discoideum
- Author(s): Taylor, Natalie Marie
- et al.
A putative novel Ras effector, TJ1, was identified through reverse genetics and characterized through chemotaxis, developmental and biochemical assays to determine its role in Dictyostelium discoideum. Additionally, the Ras association (RA) domains within TJ1 were deleted and subsequent cell lines were characterized to determine their function in TJ1. TJ1 is required for proper chemotaxis. Compared to wild-type cells, tj1- null cells were not polarized, did not chemotax, and as a result displayed a delay in initial stages of development. Additionally, findings indicate that a fully functional TJ1 protein requires at least one of the two RA domains therein. Disruption of either of the two individual RA domains in TJ1 does not result in strong defects in chemotaxis, development or localization, whereas the deletion of both RA domains leads to a reduced ability to chemotax and therefore a subsequent delay in the stages of early development. Initial experiments suggest that there is no interaction between TJ1 and Ras proteins, however more experiments need to be conducted to further explore the role of TJ1 as a novel Ras effector in Dictyostelium. the complete mechanisms of the Ras signaling pathway is largely unknown. Characterizing TJ1 and the RA domains therein should shed light on how TJ1 is involved in Ras signaling in Dictyostelium discoideum and presumably how Ras signaling operates in other organisms based on the conservation of pathways across species