Self-assembly is important for the target membrane recruitment of a nuclear dynamin-related protein

Dynamin superfamily proteins are large GTPases that perform their cellular functions by self-assembling on their target membranes. Dynamin-related protein 6 (Drp6) associates with the nuclear membrane and performs nuclear remodeling. However, the mechanism of its recruitment to the target membrane is not known. Here, we discover that self-assembly of Drp6 is essential for its nuclear membrane recruitment. We identified four residues, 411-GKFR-414 to be essential for its self-assembly. We also demonstrated that the mutant Drp6 (Drp6GKFR-AAAA) failed to recruit to the nuclear membrane. This loss of nuclear membrane recruitment is not due to the lack of membrane binding capability, since the mutated protein was able to bind membrane prepared in vitro. Together, our results suggest that in addition to membrane binding, self-assembly of a nuclear dynamin-related protein is also important for the target membrane recruitment.