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bioRxiv · 10.1101/104471

Multiple kinesin-14 family members drive microtubule minus-end-directed transport in plant cells

Yamada, M.·Tanaka-Takiguchi, Y.·Hayashi, M.·Nishina, M.·Goshima, G.
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Abstract

Minus-end-directed cargo transport along microtubules (MTs) is exclusively driven by the molecular motor dynein in a wide variety of cell types. Interestingly, plants have lost the genes encoding dynein during evolution; the MT motors that compensate for dynein function are unknown. Here, we show that two members of the kinesin-14 family drive minus-end-directed transport in plants. Gene knockout analyses of the moss Physcomitrella patens revealed that the plant-specific class-VI kinesin-14, KCBP, is required for minus-end-directed transport of the nucleus and chloroplasts. Purified KCBP directly bound to acidic phospholipids (PLs) and unidirectionally transported PL liposomes along MTs in vitro. Thus, minus-end-directed transport of membranous cargoes might be driven by their direct interaction with this motor protein. Newly nucleated cytoplasmic MTs represent another known cargo exhibiting minus-end-directed motility, and we identified the conserved class-I kinesin-14 (ATK) as the motor involved. These results suggest that kinesin-14 motors were duplicated and developed as alternative MT-based minus-end-directed transporters in land plants.

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Yamada, M., Tanaka-Takiguchi, Y., Hayashi, M., Nishina, M., Goshima, G.. 2017-01-31. Multiple kinesin-14 family members drive microtubule minus-end-directed transport in plant cells. https://doi.org/10.1101/104471

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