Fig. 9

A wide range of further fibril interactions and organisational phenomena are observed. (A) Frames from a mNG-Col1α2 fibril deposition movie. Three fibrils highlighted by black arrows grow towards each other before joining at the red arrow. Scale = 2 μm. (B) A fibril marked by a red arrow straightens as if under tension. Two corner attachment points are marked by black arrows between which straightening occurs. Scale = 10 μm. (C) Growing fibrils produce a loop structure that is further strengthened by addition of more mNG-Col1α2 to give a thick loop. Tip of fibril that loops back indicated by black arrow. Red arrow shows where it rejoins the existing bundle. Scale = 2 μm. (D) Existing fibrils can be pulled into loops potentially by flow or mechanical force from the cell above. Black arrow marks the fibril forming a kink. Red arrow markes the established loop. Blue arrow marks a dark punctae of increased collagen signal at the cross over point. Both of these loops could represent further sites of attachment for another motile cell. Scale = 2 μm. (E) Frames from a mNG-Col1α2 fibril deposition movie. Two separate mNG-Col1α2 labeled fibrils intertwine around each other followed by an increase in fibril intensity and width. The tip of each growing fibril is marked by a black or red arrow. For all movies the images were acquired at 5 min intervals. 12 frames per hour. Time stamps are included on each frame. Scale = 5 μm.