TY  - JOUR
AU  - Schäfer, C.
AU  - Faust, U.
AU  - Kirchgeßner, N.
AU  - Merkel, R.
AU  - Hoffmann, B.
TI  - The Filopodium: A stable structure with highly regulated repetitive cycles of elongation and persistence
JO  - Cell adhesion & migration
VL  - 5
SN  - 1933-6918
CY  - Austin, Tex.
PB  - Landes Bioscience
M1  - PreJuSER-21270
SP  - 431 - 438
PY  - 2011
N1  - Record converted from VDB: 12.11.2012
AB  - The ability of mammalian cells to adhere and to migrate is an essential prerequisite to form higher organisms. Early migratory events include substrate sensing, adhesion formation, actin bundle assembly and force generation. Latest research revealed that filopodia are important not only for sensing the substrate but for all of the aforementioned highly regulated processes. However, the exact regulatory mechanisms are still barely understood. Here, we demonstrate that filopodia of human keratinocytes exhibit distinct cycles of repetitive elongation and persistence. A single filopodium thereby is able to initiate the formation of several stable adhesions. Every single filopodial cycle is characterized by an elongation phase, followed by a stabilization time and in many cases a persistence phase. The whole process is strongly connected to the velocity of the lamellipodial leading edge, characterized by a similar phase behavior with a slight time shift compared to filopodia and a different velocity. Most importantly, re-growth of existing filopodia is induced at a sharply defined distance between the filopodial tip and the lamellipodial leading edge. On the molecular level this re-growth is preceded by a strong filopodial reduction of the actin bundling protein fascin. This reduction is achieved by a switch to actin polymerization without fascin incorporation at the filopodial tip and therefore subsequent out-transport of the cross-linker by actin retrograde flow.
KW  - Actins: chemistry
KW  - Actins: metabolism
KW  - Carrier Proteins: metabolism
KW  - Cell Adhesion: physiology
KW  - Cell Adhesion Molecules: chemistry
KW  - Cell Adhesion Molecules: metabolism
KW  - Cell Line
KW  - Cell Movement
KW  - Focal Adhesions: metabolism
KW  - Humans
KW  - Keratinocytes: cytology
KW  - Keratinocytes: metabolism
KW  - Microfilament Proteins: chemistry
KW  - Microfilament Proteins: metabolism
KW  - Polymerization
KW  - Pseudopodia: chemistry
KW  - Pseudopodia: metabolism
KW  - Actins (NLM Chemicals)
KW  - Carrier Proteins (NLM Chemicals)
KW  - Cell Adhesion Molecules (NLM Chemicals)
KW  - Microfilament Proteins (NLM Chemicals)
KW  - fascin (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:21975552
C2  - pmc:PMC3218610
UR  - <Go to ISI:>//WOS:000300713700008
DO  - DOI:10.4161/cam.5.5.17400
UR  - https://juser.fz-juelich.de/record/21270
ER  -