Engineering Approaches to Biomolecular Motors

Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts

37-POS Board 37 Engineering a Processive Minus End-directed Kinesin-14 for Long-range Transport on Microtubules Yuh-Ru Julie Lee 1 , Kuo-Fu Tseng 2 , Pan Wang 2,3 , Joel Bowen 4 , Lijun Guo 3 , Weihong Qiu 2,6 , and Bo Liu 1 1 Department of Plant Biology, University of California, Davis, CA, USA, 2 Department of Physics, Oregon State University, Corvallis, OR, USA, 3 School of Physics and Electronics, Henan University, Kaifeng, Henan, China, 4 Department of Mathematics, Oregon State University, Corvallis, OR, USA, 5 Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA. Retrograde transport along microtubules in animal and fungal cells is carried out mostly by cytoplasmic dynein, a minus end-directed motor with high intrinsic processivity. In contrast, land plants lack cytoplasmic dynein and contain instead a large number of minus end-directed kinesins. However, none of these minus end-directed kinesins in plants has been found to be intrinsically processive. We report here that the minus end-directed kinesin OsKCH2 from the rice plant (Oryza sativa) is intrinsically processive on the microtubule, which is enabled by a nonmotor domain (CC2) that enhances its affinity for the microtubule. Our findings suggest that plants have evolved unconventional minus end-directed kinesins as efficient substitutes for cytoplasmic dynein. Interestingly, substituting CC2 in OsKCH1 – a nonprocessive kinesin-14 from the rice plant – with that from OsKCH2 results in a kinesin-14 chimera (OsKCH1P) that moves processively on the microtubule. We suggest that OsKCH1P is an important tool for dissecting the in vivo functional significance of OskCH1 processivity.

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