Abstract:
:We used optical tweezers to analyze the effect of jasplakinolide and cyclodextrin on the force exerted by lamellipodia from developing growth cones (GCs) of isolated dorsal root ganglia (DRG) neurons. We found that 25 nM of jasplakinolide, which is known to inhibit actin filament turnover, reduced both the maximal exerted force and maximal velocity during lamellipodia leading-edge protrusion. By using atomic force microscopy, we verified that cyclodextrin, which is known to remove cholesterol from membranes, decreased the membrane stiffness of DRG neurons. Lamellipodia treated with 2.5 mM of cyclodextrin exerted a larger force, and their leading edge could advance with a higher velocity. Neither jasplakinolide nor cyclodextrin affected force or velocity during lamellipodia retraction. The amplitude and frequency of elementary jumps underlying force generation were reduced by jasplakinolide but not by cyclodextrin. The action of both drugs at the used concentration was fully reversible. These results support the notion that membrane stiffness provides a selective pressure that shapes force generation, and confirm the pivotal role of actin turnover during protrusion.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Amin L,Ercolini E,Shahapure R,Migliorini E,Torre Vdoi
10.1016/j.bpj.2012.04.036subject
Has Abstractpub_date
2012-06-06 00:00:00pages
2451-60issue
11eissn
0006-3495issn
1542-0086pii
S0006-3495(12)00510-3journal_volume
102pub_type
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