A PIK3C3-Ankyrin-B-Dynactin pathway promotes axonal growth and multiorganelle transport

作者：Lorenzo Damaris Nadia; Badea Alexandra; Davis Jonathan; Hostettler Janell; He Jiang; Zhong Guisheng; Zhuang Xiaowei; Bennett Vann^*

来源：The Journal of Cell Biology, 2014, 207(6): 735-752.

DOI：10.1083/jcb.201407063

Axon growth requires long-range transport of organelles, but how these cargoes recruit their motors and how their traffic is regulated are not fully resolved. In this paper, we identify a new pathway based on the class III PI3-kinase (PIK3C3), ankyrin-B (AnkB), and dynactin, which promotes fast axonal transport of synaptic vesicles, mitochondria, endosomes, and lysosomes. We show that dynactin associates with cargo through AnkB interactions with both the dynactin subunit p62 and phosphatidylinositol 3-phosphate (PtdIns(3) P) lipids generated by PIK3C3. AnkB knockout resulted in shortened axon tracts and marked reduction in membrane association of dynactin and dynein, whereas it did not affect the organization of spectrin-actin axonal rings imaged by 3D-STORM. Loss of AnkB or of its linkages to either p62 or PtdIns(3) P or loss of PIK3C3 all impaired organelle transport and particularly retrograde transport in hippocampal neurons. Our results establish new functional relationships between PIK3C3, dynactin, and AnkB that together promote axonal transport of organelles and are required for normal axon length.

• 出版日期2014-12-22