Minus end-directed kinesin-14 KIFC1 regulates the positioning and architecture of the Golgi apparatus

Abstract

The Golgi apparatus is the central organelle along the eukaryotic secretory and endocytic pathway. In non-polarized mammalian cells, the Golgi complex is usually located proximal to the nucleus at the cell center and is closely associated with the microtubule organizing center. Microtubule networks are essential in the organization and central localization of the Golgi apparatus, but the molecular basis underlying these processes are poorly understood. Here we reveal that minus end-directed kinesin-14 KIFC1 proteins are required for the structural integrity and positioning of the Golgi complex in non-polarized mammalian cells. Remarkably, we found that the motor domain of kinesin-14 KIFC1 regulates the recognition and binding of the Golgi and KIFC1 also statically binds to the microtubules via its tail domain. These findings reveal a new stationary binding model that kinesin-14 KIFC1 proteins function as crosslinkers between the Golgi apparatus and the microtubules and contribute to the central positioning and structural maintenance of the Golgi apparatus.