Rapid actin transport during cell protrusion.
Transformed rat fibroblasts expressing two variants of green fluorescent protein, each fused to beta-actin, were used to study actin dynamics during cell protrusion. The recently developed FLAP (fluorescence localization after photobleaching) method permits the tracking of one fluorophore after localized photobleaching by using the other as a colocalized reference. Here, by visualizing the ratio of bleached to total molecules, we found that actin was delivered to protruding zones of the leading edge of the cell at speeds that exceeded 5 micrometers per second. Monte Carlo modeling confirmed that this flow cannot be explained by diffusion and may involve active transport.
Zicha
Daniel
D
Light Microscopy, Cancer Research UK, Lincoln's Inn Fields Laboratories, London WC2A 3PX, UK.
Dobbie
Ian M
IM
Holt
Mark R
MR
Monypenny
James
J
Soong
Daniel Y H
DY
Gray
Colin
C
Dunn
Graham A
GA
D000199:Actins / Q000378:metabolism*; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001381:Azepines / Q000494:pharmacology; D001426:Bacterial Proteins / Q000378:metabolism; D001693:Biological Transport, Active; D001704:Biopolymers; D002461:Cell Line, Transformed; D002465:Cell Movement; D047630:Depsipeptides; D004058:Diffusion; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005453:Fluorescence; D036681:Fluorescence Recovery After Photobleaching; D005470:Fluorometry; D049452:Green Fluorescent Proteins; D007091:Image Processing, Computer-Assisted; D047908:Intracellular Signaling Peptides and Proteins; D008164:Luminescent Proteins / Q000378:metabolism; D018613:Microscopy, Confocal; D009010:Monte Carlo Method; D009219:Myosin-Light-Chain Kinase / Q000037:antagonists & inhibitors / Q000378:metabolism; D009281:Naphthalenes / Q000494:pharmacology; D015739:Nocodazole / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000494:pharmacology; D038761:Photobleaching; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D011554:Pseudopodia / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014407:Tumor Cells, Cultured; D054460:rho-Associated Kinases
D000199:Actins; D000577:Amides; D001381:Azepines; D001426:Bacterial Proteins; D001704:Biopolymers; D047630:Depsipeptides; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D008164:Luminescent Proteins; D009281:Naphthalenes; D010456:Peptides, Cyclic; D011725:Pyridines; D011993:Recombinant Fusion Proteins; C054562:yellow fluorescent protein, Bacteria; C057531:jasplakinolide; C070571:ML 7; C108830:Y 27632; D049452:Green Fluorescent Proteins; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D009219:Myosin-Light-Chain Kinase; D015739:Nocodazole