Dual localized kinesin‐12 POK 2 plays multiple roles during cell division and interacts with MAP 65‐3

Kinesins are versatile nano‐machines that utilize variable non‐motor domains to tune specific motor microtubule encounters. During plant cytokinesis, the kinesin‐12 orthologs, PHRAGMOPLAST ORIENTING KINESIN ( POK )1 and POK 2, are essential for rapid centrifugal expansion of the cytokinetic apparatus, the phragmoplast, toward a pre‐selected cell plate fusion site at the cell cortex. Here, we report on the spatio‐temporal localization pattern of POK 2, mediated by distinct protein domains. Functional dissection of POK 2 domains revealed the association of POK 2 with the site of the future cell division plane and with the phragmoplast during cytokinesis. Accumulation of POK 2 at the phragmoplast midzone depends on its functional POK 2 motor domain and is fine‐tuned by its carboxy‐terminal region that also directs POK 2 to the division site. Furthermore, POK 2 likely stabilizes the phragmoplast midzone via interaction with the conserved microtubule‐associated protein MAP 65‐3/ PLEIADE , a well‐established microtubule cross‐linker. Collectively, our results suggest that dual localized POK 2 plays multiple roles during plant cell division.