Single Molecule Imaging Reveals Differences in Microtubule Track Selection Between Kinesin Motors
نویسندگان
چکیده
Cells generate diverse microtubule populations by polymerization of a common alpha/beta-tubulin building block. How microtubule associated proteins translate microtubule heterogeneity into specific cellular functions is not clear. We evaluated the ability of kinesin motors involved in vesicle transport to read microtubule heterogeneity by using single molecule imaging in live cells. We show that individual Kinesin-1 motors move preferentially on a subset of microtubules in COS cells, identified as the stable microtubules marked by post-translational modifications. In contrast, individual Kinesin-2 (KIF17) and Kinesin-3 (KIF1A) motors do not select subsets of microtubules. Surprisingly, KIF17 and KIF1A motors that overtake the plus ends of growing microtubules do not fall off but rather track with the growing tip. Selection of microtubule tracks restricts Kinesin-1 transport of VSVG vesicles to stable microtubules in COS cells whereas KIF17 transport of Kv1.5 vesicles is not restricted to specific microtubules in HL-1 myocytes. These results indicate that kinesin families can be distinguished by their ability to recognize microtubule heterogeneity. Furthermore, this property enables kinesin motors to segregate membrane trafficking events between stable and dynamic microtubule populations.
منابع مشابه
Motor Reattachment Kinetics Play a Dominant Role in Multimotor-Driven Cargo Transport.
Kinesin-based cargo transport in cells frequently involves the coordinated activity of multiple motors, including kinesins from different families that move at different speeds. However, compared to the progress at the single-molecule level, mechanisms by which multiple kinesins coordinate their activity during cargo transport are poorly understood. To understand these multimotor coordination m...
متن کاملSingle-molecule behavior of monomeric and heteromeric kinesins.
Conventional kinesin is capable of long-range, processive movement along microtubules, a property that has been assumed to be important for its role in membrane transport. Here we have investigated whether the Caenorhabditis elegans monomeric kinesin unc104 and the sea urchin heteromeric kinesin KRP85/95, two other members of the kinesin superfamily that function in membrane transport, are also...
متن کاملNative kinesin-1 does not bind preferentially to GTP-tubulin-rich microtubules in vitro.
Molecular motors such as kinesin-1 work in small teams to actively shuttle cargos in cells, for example in polarized transport in axons. Here, we examined the potential regulatory role of the nucleotide state of tubulin on the run length of cargos carried by multiple kinesin motors, using an optical trapping-based in vitro assay. Based on a previous report that kinesin binds preferentially to G...
متن کاملA new cooperation mechanism of kinesin motors when extracting membrane tube
Membrane tubes are important elements for living cells to organize many functions. Experiments have found that membrane tube can be extracted from giant lipid vesicles by a group of kinesin. How these motors cooperate in extracting the fluid-like membrane tube is still unclear. In this paper, we propose a new cooperation mechanism called two-track-dumbbell model, in which kinesin is regarded as...
متن کاملSecondary structure and compliance of a predicted flexible domain in kinesin-1 necessary for cooperation of motors.
Although the mechanism by which a kinesin-1 molecule moves individually along a microtubule is quite well-understood, the way that many kinesin-1 motor proteins bound to the same cargo move together along a microtubule is not. We identified a 60-amino-acid-long domain, termed Hinge 1, in kinesin-1 from Drosophila melanogaster that is located between the coiled coils of the neck and stalk domain...
متن کامل