Abstract:
:Lamellipodia of crawling cells represent both the motor for cell advance and the primary building site for the actin cytoskeleton. The organization of actin in the lamellipodium reflects actin dynamics and is of critical importance for the mechanism of cell motility. In previous structural studies, the lamellipodial actin network was analyzed primarily by electron microscopy (EM). An understanding of lamellipodial organization would benefit significantly if the EM data were complemented and put into a kinetic context by establishing correspondence with structural features observable at the light microscopic level in living cells. Here, we use an enhanced phase contrast microscopy technique to visualize an apparent long-range diagonal actin meshwork in the advancing lamellipodia of living cells. Visualization of this meshwork permitted a correlative light and electron microscopic approach that validated the underlying organization of lamellipodia. The linear features in the light microscopic meshwork corresponded to regions of greater actin filament density. Orientation of features was analyzed quantitatively and compared with the orientation of actin filaments at the EM level. We infer that the light microscopic meshwork reflects the orientational order of actin filaments which, in turn, is related to their branching angle.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Verkhovsky AB,Chaga OY,Schaub S,Svitkina TM,Meister JJ,Borisy GGdoi
10.1091/mbc.e02-10-0630keywords:
subject
Has Abstractpub_date
2003-11-01 00:00:00pages
4667-75issue
11eissn
1059-1524issn
1939-4586pii
E02-10-0630journal_volume
14pub_type
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