GAPS and GEFs for LRRK2

As it is known that LRRK2 kinase activity is controlled by GTPase activity, there is a general query about the role of GEFs and GAPs in turning on/off of the GTPase activity. The partial crystal structure of LRRK2 - ROC domain indicates that the protein forms a dimer through generated by extensive domain-swapping. PD-associated mutants (R1441 and I1371) located at the interface of the two monomers provide exquisite interactions to stabilize the ROC dimer.

However, with the minimal quantity of LRRK2 expressed, it is not known which GEF's or GAPs play a role in the GDP/GTP exchange. There has not yet been and GDP-locked or GTP-locked structure / mutant of LRRK2 known. If someone comes up with either or both of them, a yeast-two hybrid approach can be used to find out the GAPs or GEFs.