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Modulation of substrate adhesion dynamics via microtubule targeting requires kinesin-1.

Krylyshkina O, Kaverina I, Kranewitter W, Steffen W, Alonso MC, Cross RA, Small JV - J. Cell Biol. (2002)

Bottom Line: Small. 1999.Cell Biol. 146:1033-1043).In comparison, a block of kinesin-1 activity, either via microinjection of the SUK-4 antibody or of a kinesin-1 heavy chain construct mutated in the motor domain, induced a dramatic increase in the size and reduction in number of substrate adhesions, mimicking the effect observed after microtubule disruption by nocodazole.

View Article: PubMed Central - PubMed

Affiliation: Institute of Molecular Biology, Austrian Academy of Sciences, Billrothsthstrasse 11, Salzburg 5020, Austria.

ABSTRACT
Recent studies have shown that the targeting of substrate adhesions by microtubules promotes adhesion site disassembly (Kaverina, I., O. Krylyshkina, and J.V. Small. 1999. J. Cell Biol. 146:1033-1043). It was accordingly suggested that microtubules serve to convey a signal to adhesion sites to modulate their turnover. Because microtubule motors would be the most likely candidates for effecting signal transmission, we have investigated the consequence of blocking microtubule motor activity on adhesion site dynamics. Using a function-blocking antibody as well as dynamitin overexpression, we found that a block in dynein-cargo interaction induced no change in adhesion site dynamics in Xenopus fibroblasts. In comparison, a block of kinesin-1 activity, either via microinjection of the SUK-4 antibody or of a kinesin-1 heavy chain construct mutated in the motor domain, induced a dramatic increase in the size and reduction in number of substrate adhesions, mimicking the effect observed after microtubule disruption by nocodazole. Blockage of kinesin activity had no influence on either the ability of microtubules to target substrate adhesions or on microtubule polymerisation dynamics. We conclude that conventional kinesin is not required for the guidance of microtubules into substrate adhesions, but is required for the focal delivery of a component(s) that retards their growth or promotes their disassembly.

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Kinesin inhibition does not block the targeting of substrate adhesions by microtubules. Figure shows video frames from a SUK-4 injected Xenopus fibroblast that was preinjected with Cy-3-tubulin and TAMRA-vinculin. Arrows indicate targeting events. Time is in minutes and seconds.
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fig10: Kinesin inhibition does not block the targeting of substrate adhesions by microtubules. Figure shows video frames from a SUK-4 injected Xenopus fibroblast that was preinjected with Cy-3-tubulin and TAMRA-vinculin. Arrows indicate targeting events. Time is in minutes and seconds.

Mentions: Microtubule targeting was also not affected by kinesin inhibition. This was analyzed by first coinjecting cells with TAMRA-vinculin and Cy-3 tubulin, and thereafter with either SUK-4 Ab or T93N kinesin. Fig. 9 and Video 7 (available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1) show microtubule targeting of substrate adhesions in control Xenopus fibroblasts. After either SUK-4 antibody injection (Fig. 10 ; Video 6, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1) or the injection of T93N kinesin (Video 9, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1), adhesion site targeting occurred as in control cells. However, as might be expected, the focal adhesion dynamics in cells injected with SUK-4 Ab or T93N kinesin resembled that seen in nocodazole-treated cells (Video 8, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1). Thus, adhesions in retracting edges commonly slid and fused to produce larger and fewer adhesions (compare control and SUK-4–injected cell) (Video 6, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1).


Modulation of substrate adhesion dynamics via microtubule targeting requires kinesin-1.

Krylyshkina O, Kaverina I, Kranewitter W, Steffen W, Alonso MC, Cross RA, Small JV - J. Cell Biol. (2002)

Kinesin inhibition does not block the targeting of substrate adhesions by microtubules. Figure shows video frames from a SUK-4 injected Xenopus fibroblast that was preinjected with Cy-3-tubulin and TAMRA-vinculin. Arrows indicate targeting events. Time is in minutes and seconds.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2199234&req=5

fig10: Kinesin inhibition does not block the targeting of substrate adhesions by microtubules. Figure shows video frames from a SUK-4 injected Xenopus fibroblast that was preinjected with Cy-3-tubulin and TAMRA-vinculin. Arrows indicate targeting events. Time is in minutes and seconds.
Mentions: Microtubule targeting was also not affected by kinesin inhibition. This was analyzed by first coinjecting cells with TAMRA-vinculin and Cy-3 tubulin, and thereafter with either SUK-4 Ab or T93N kinesin. Fig. 9 and Video 7 (available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1) show microtubule targeting of substrate adhesions in control Xenopus fibroblasts. After either SUK-4 antibody injection (Fig. 10 ; Video 6, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1) or the injection of T93N kinesin (Video 9, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1), adhesion site targeting occurred as in control cells. However, as might be expected, the focal adhesion dynamics in cells injected with SUK-4 Ab or T93N kinesin resembled that seen in nocodazole-treated cells (Video 8, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1). Thus, adhesions in retracting edges commonly slid and fused to produce larger and fewer adhesions (compare control and SUK-4–injected cell) (Video 6, available at http://www.jcb.org/cgi/content/full/jcb.200105051/DC1).

Bottom Line: Small. 1999.Cell Biol. 146:1033-1043).In comparison, a block of kinesin-1 activity, either via microinjection of the SUK-4 antibody or of a kinesin-1 heavy chain construct mutated in the motor domain, induced a dramatic increase in the size and reduction in number of substrate adhesions, mimicking the effect observed after microtubule disruption by nocodazole.

View Article: PubMed Central - PubMed

Affiliation: Institute of Molecular Biology, Austrian Academy of Sciences, Billrothsthstrasse 11, Salzburg 5020, Austria.

ABSTRACT
Recent studies have shown that the targeting of substrate adhesions by microtubules promotes adhesion site disassembly (Kaverina, I., O. Krylyshkina, and J.V. Small. 1999. J. Cell Biol. 146:1033-1043). It was accordingly suggested that microtubules serve to convey a signal to adhesion sites to modulate their turnover. Because microtubule motors would be the most likely candidates for effecting signal transmission, we have investigated the consequence of blocking microtubule motor activity on adhesion site dynamics. Using a function-blocking antibody as well as dynamitin overexpression, we found that a block in dynein-cargo interaction induced no change in adhesion site dynamics in Xenopus fibroblasts. In comparison, a block of kinesin-1 activity, either via microinjection of the SUK-4 antibody or of a kinesin-1 heavy chain construct mutated in the motor domain, induced a dramatic increase in the size and reduction in number of substrate adhesions, mimicking the effect observed after microtubule disruption by nocodazole. Blockage of kinesin activity had no influence on either the ability of microtubules to target substrate adhesions or on microtubule polymerisation dynamics. We conclude that conventional kinesin is not required for the guidance of microtubules into substrate adhesions, but is required for the focal delivery of a component(s) that retards their growth or promotes their disassembly.

Show MeSH
Related in: MedlinePlus