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Fig. 5
Extracellular matrix (ECM) is required to couple movements of neural plate and mesoderm. A: First frame of time-lapse from wild-type (wt) embryo. Image is in transverse plane and includes left-hand side and midline of neural plate (orientation shown in E). Evl, indicates selected cells in enveloping layer (blue dots), neural plate (yellow dots), and mesoderm (red dots). Arrow indicates midline. Cell nuclei are labeled with H2A-GFP. B: Projection of frames 1 to 10 of time-lapse movie from wt embryo, showing the tracks of the selected cells in the EVL, neural plate and mesoderm indicated in A. C: First frame of time-lapse from embryo depleted of laminin and fibronectin by morpholino injection. Image is in transverse plane and includes left-hand side and midline of neural plate (orientation shown in E). Evl, indicates selected cells in enveloping layer (blue dots), neural plate (yellow dots), and mesoderm (red dots). Arrow indicates midline. Cell nuclei are labeled with H2A-GFP. D: Projection of frames 1 to 10 of time-lapse movie from laminin and fibronectin depleted embryo, showing the tracks of the EVL, neural plate and mesoderm cells indicated in C. E: Diagrams indicating orientation and position of time-lapse movies used for images in A to D and analyses in F to I. Blue layer is enveloping layer (EVL), yellow layer is neural plate (NP) and red layer is mesoderm (MES). F: Trajectories of neural (yellow) and mesodermal (red) nuclei in laminin and fibronectin depleted embryos. G-I: Analyses in cell directionality (G), persistence (H), and angular speed (I), reveals uncoupled behavior of neural plate and mesoderm cells in Fn1/LamC1 morpholno embryos.