AI Article Synopsis
- Kinesin II is a type of motor protein that moves organelles towards the plus end of microtubules, but the way it connects with these organelles is not well understood.
- Using Xenopus laevis melanophores, researchers found that the dynactin complex, which typically anchors the dynein motor, also links kinesin II to organelles during melanosome movement.
- Biochemical analysis showed that the cargo-binding subunit of kinesin II (XKAP) interacts directly with a component of dynactin (p150Glued), indicating that dynactin plays a crucial role in coordinating the functions of both kinesin II and dynein in cellular transport
Article Abstract
Kinesin II is a heterotrimeric plus end-directed microtubule motor responsible for the anterograde movement of organelles in various cell types. Despite substantial literature concerning the types of organelles that kinesin II transports, the question of how this motor associates with cargo organelles remains unanswered. To address this question, we have used Xenopus laevis melanophores as a model system. Through analysis of kinesin II-mediated melanosome motility, we have determined that the dynactin complex, known as an anchor for cytoplasmic dynein, also links kinesin II to organelles. Biochemical data demonstrates that the putative cargo-binding subunit of Xenopus kinesin II, Xenopus kinesin II-associated protein (XKAP), binds directly to the p150Glued subunit of dynactin. This interaction occurs through aa 530-793 of XKAP and aa 600-811 of p150Glued. These results reveal that dynactin is required for transport activity of microtubule motors of opposite polarity, cytoplasmic dynein and kinesin II, and may provide a new mechanism to coordinate their activities.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2172679 | PMC |
| http://dx.doi.org/10.1083/jcb.200210066 | DOI Listing |
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