Control of lipid domain organization by a biomimetic contractile actomyosin cortex
- Max-Planck Institute of Biochemistry, Germany
- Ludwig-Maximilans-University, Germany
Figures
Figure 1
Minimal actin cortex on supported phase-separated lipid membranes.
(A) Illustration depicting the preparation of the SLB and the coupling of actin filaments to the membrane (adapted from [Vogel et al., 2013a]). (B) Since DiD is known to partition specifically to …
Figure 2
Impact of actin filaments on the lateral organization of phase-separated membranes.
(A) Scheme of a phase separation experiment with and without MAC is shown with circles indicating time points when fluorescent images were acquired. (B) Size distribution of lipid domains changed in …
Figure 3
Actomyosin contraction governs lateral membrane organization for various lipid compositions.
(A) TIRFM time-lapse images of a contracting MAC with Alexa-488-phalloidin labeled actin filaments and DiD-labeled Ld domains of a 1:2:1 DOPC:DPPC:Cholesterol mixture. Scale bar, 10 µm. (B) For the …
Figure 4
Lipid monolayer domain shape changes and fusion events induced by actomyosin contractions.
(A) Confocal spinning disk microscope images of Alexa-488-phalloidin-labeled actin filaments coupled to a ATTO655-DOPE-labeled lipid monolayer (3:3:1 DOPC:PSM:Cholesterol) in the absence of …
Scheme 1
Top (A) and lateral (B) schematic view of the PTFE chamber (adapted from [Chwastek and Schwille, 2013]).
https://doi.org/10.7554/eLife.24350.014
Author response image 1
Confocal Spinning Disk images of the additional lipid monolayer mixture (1:2:1 DOPC:DPPC:Cholesterol).
Actin filaments close to the phase boundaries align to the circular shape of the liquid condensed (ordered) Lc domains because the line tension energy dominates over the actin filament wetting …
Videos
Video 1
Myosin-induced actin rearrangements in a minimal actin cortex (MAC) combined with a supported phase-separated lipid bilayer.
MAC with a supported phase-separated membrane (1:2:1 DOPC:DPPC:Cholesterol) containing Alexa-488-phalloidin-labeled actin filaments (green) exhibits dynamic rearrangements of actin filaments after …
Video 2
Shape changes, rearrangements and fusion events of Ld domains during actomyosin contraction.
The phase-separated membrane (1:2:1 DOPC:DPPC:Cholesterol) containing DiD labeled Ld domains (red) is shown in the left channel. The middle channel shows Alexa-488-phalloidin labeled actin filaments …
Video 3
Splitting, shape changes and deformations of Ld domains during actomyosin contraction.
The phase-separated membrane (1:2:1 DOPC:DPPC:Cholesterol) containing DiD labeled Ld domains (red) is shown in the left channel. The middle channel shows Alexa-488-phalloidin-labeled actin filaments …
Video 4
Ld domain movement, splitting and ingression during actomyosin contraction.
The phase-separated membrane (1:2:1 DOPC:DPPC:Cholesterol) containing DiD-labeled Ld domains (red) is shown in the left channel. The middle channel shows Alexa-488-phalloidin-labeled actin filaments …
Video 5
Shape changes, rearrangements and fusion events of Lo domains during actomyosin contraction.
The phase-separated and DiD labeled (red) membrane (3:3:1 DOPC:PSM:Cholesterol) containing Lo domains (dark) is shown in the upper channel. The middle channel shows Alexa-488-phalloidin-labeled …
Video 6
Fusion event of a Lo domain during actomyosin contraction.
A small Lo domain is stretched by actin filaments thereby pulling the domain toward a larger domain leading eventually to fusion of both Lo domains. The phase-separated and DiD-labeled (red) …
Video 7
Disappearance of small Lo domains during actomyosin contraction.
Small Lo domains often vanish during actomyosin contractions. The phase-separated and DiD-labeled (red) membrane (3:3:1 DOPC:PSM:Cholesterol) containing Lo domains (dark) is shown in the left …
Video 8
Shape changes and fusion events during actomyosin contraction of Lc domains in a MAC combined with a phase-separated lipid monolayer.
Myofilaments in the presence of ATP led to the contraction of the actin layers and to shape changes and fusion events of the Lc domains. The phase-separated lipid monolayer (3:3:1 …
