ZFYVE27 (Protrudin) was originally identified as an interacting partner of spastin, which is most frequently mutated in hereditary spastic paraplegia. ZFYVE27 is a novel member of FYVE family, which is implicated in the formation of neurite extensions by promoting directional membrane trafficking in neurons. Now, through a yeast two-hybrid screen, we have identified that ZFYVE27 interacts with itself and the core interaction region resides within the third hydrophobic region (HR3) of the protein. We confirmed the ZFYVE27's self-interaction in the mammalian cells by co-immunoprecipitation and co-localization studies. To decipher the oligomeric nature of ZFYVE27, we performed sucrose gradient centrifugation and showed that ZFYVE27 oligomerizes into dimer/tetramer forms. Sub-cellular fractionation and Triton X-114 membrane phase separation analysis indicated that ZFYVE27 is a peripheral membrane protein. Furthermore, ZFYVE27 also binds to phosphatidylinositol 3-phosphate lipid moiety. Interestingly, cells expressing ZFYVE27 ΔHR3 failed to produce protrusions instead caused swelling of cell soma. When ZFYVE27 ΔHR3 was co-expressed with wild-type ZFYVE27 (ZFYVE27 WT), it exerted a dominant negative effect on ZFYVE27 WT as the cells co-expressing both proteins were also unable to induce protrusions and showed cytoplasmic swelling. Altogether, it is evident that a functionally active form of oligomer is crucial for ZFYVE27 ability to promote neurite extensions. © 2011 Pantakani et al.
Pantakani, D. V. K., Czyzewska, M. M., Sikorska, A., Bodda, C., & Mannan, A. U. (2011). Oligomerization of ZFYVE27 (Protrudin) is necessary to promote neurite extension. PLoS ONE, 6(12). https://doi.org/10.1371/journal.pone.0029584