TY  - JOUR
A1  - Gerhardt, Matthias
A1  - Ecke, Mary
A1  - Walz, Michael
A1  - Stengl, Andreas
A1  - Beta, Carsten
A1  - Gerisch, Günther
T1  - Actin and PIP3 waves in giant cells reveal the inherent length scale of an excited state
JF  - Journal of cell science
N2  - The membrane and actin cortex of a motile cell can autonomously differentiate into two states, one typical of the front, the other of the tail. On the substrate-attached surface of Dictyostelium discoideum cells, dynamic patterns of front-like and tail-like states are generated that are well suited to monitor transitions between these states. To image large-scale pattern dynamics independently of boundary effects, we produced giant cells by electric-pulse-induced cell fusion. In these cells, actin waves are coupled to the front and back of phosphatidylinositol (3,4,5)-trisphosphate (PIP3)-rich bands that have a finite width. These composite waves propagate across the plasma membrane of the giant cells with undiminished velocity. After any disturbance, the bands of PIP3 return to their intrinsic width. Upon collision, the waves locally annihilate each other and change direction; at the cell border they are either extinguished or reflected. Accordingly, expanding areas of progressing PIP3 synthesis become unstable beyond a critical radius, their center switching from a front-like to a tail-like state. Our data suggest that PIP3 patterns in normal-sized cells are segments of the self-organizing patterns that evolve in giant cells.
KW  - Actin waves
KW  - PIP3 signals
KW  - Excitable systems
KW  - Cell polarity
KW  - Cell fusion
Y1  - 2014
U6  - https://doi.org/10.1242/jcs.156000
SN  - 0021-9533
SN  - 1477-9137
VL  - 127
IS  - 20
SP  - 4507
EP  - 4517
PB  - Company of Biologists Limited
CY  - Cambridge
ER  -