Kinesin-12

Kinesin-12, also known as Kif15, is a microtubule-based motor protein that contributes to spindle assembly and axonal transport in both neuronal and non-neuronal cells^[1][2][3]. Mechanistically, it regulates microtubule bundling, plus-end stabilization, and cross-linking, which are essential for bipolar spindle formation during mitosis^[3][4]. Unlike kinesin-5 (Eg5), kinesin-12 can interact with actin and exhibits tetrameric track-switching behavior, allowing navigation of intersecting microtubule networks^[1][5][4]. In developing neurons, kinesin-12 modulates axonal growth, branching, and growth cone dynamics, with depletion causing faster axonal extension but reduced branching and growth cone size^[1][6]. In disease or pharmacological models, kinesin-12 mediates resistance to kinesin-5 inhibitors in cancer cell lines, highlighting its compensatory role in spindle assembly^[2][7]. Plant kinesin-12 proteins, such as NtKRP and POK1/2, regulate embryo development, cell plate formation, and cortical division zone maintenance, reflecting functional diversification across kingdoms^{[8][9][10][11]}. Compared with other isoforms, kinesin-12 shows unique localization heterogeneity, plus-end-directed motility, and cargo-binding versatility that distinguish it from kinesin-5 and kinesin-4 family members^[12][3][10]. Small-molecule modulation of kinesin-12 has potential experimental applications, as its inhibition or depletion impacts microtubule organization, cell proliferation, and directional transport^[4][6]. Collectively, these features underscore kinesin-12’s integral role in mitotic regulation, neuronal development, and plant cytokinesis.

References: