A non-mitotic CENP-E homolog in Dictyostelium discoideum with slow motor activity

作者：Koesem Sueleyman; Oekten Zeynep; Thi Hieu Ho; Trommler Gudrun; Koonce Michael P; Samereier Matthias; Mueller Taubenberger Annette

来源：Biochemical and Biophysical Research Communications, 2013, 431(3): 490-495.

DOI：10.1016/j.bbrc.2013.01.030

• CENP-E
• Dictyostelium discoideum
• Kinesin
• Microtubules

Kinesins are ATP-dependent molecular motors that mediate unidirectional intracellular transport along microtubules. Dictyostelium discoideum has 13 different kinesin isoforms including two members of the kinesin-7 family, Kif4 and Kif11. While Kif4 is structurally and functionally related to centromere-associated CENP-E proteins involved in the transport of chromosomes to the poles during mitosis, the function of the unusually short CENP-E variant Kif11 is unclear. Here we show that orthologs of short CENP-E variants are present in plants and fungi, and analyze functional properties of the Dictyostelium CENP-E version, Kiln Gene knockout mutants reveal that Kif11 is not required for mitosis or development. Imaging of GFP-labeled Kif11 expressing Dictyostelium cells indicates that Kif11 is a plus-end directed motor that accumulates at microtubule plus ends. By multiple motor gliding assays, we show that Kif11 moves with an average velocity of 38 nm/s, thus defining Kif11 as a very slow motor. The activity of the Kif11 motor appears to be modulated via interactions with the non-catalytic tail region. Our work highlights a subclass of kinesin-7-like motors that function outside of a role in mitosis.

• 出版日期2013-2-15