Elul, T. and Keller, R. E. (2000) Monopolar protrusive activity: a new morphogenetic cell behavior in the neural plate dependent on vertical interactions with the mesoderm in Xenopus. Developmental Biology

Figure 12. Schematic summary of our findings. In deep neural explants without notoplate, cells express bipolar mediolateral motility (top). In deep neural-over-mesoderm explants, neural cells express medial protrusive activity, and notoplate cells (within the Shh expression domain) express random protrusive activity (B). Additionally, in both deep neural-over-mesoderm and deep neural explants, morphogenetic behaviors differentiate in anterior-to-posterior and lateral-to-medial progressions (top, bottom). However, in deep neural explants, motile cell behaviors differentiate in a continuous anterior-to-posterior progression (top) whereas in deep neural-over-mesoderm explants, motile behaviors differentiate in a discontinuous anterior-to-posterior progression (bottome). Blue tissue is neural, red tissue is mesodermal, and dark blue staining is Shh and F-spondin.

Links to Timelapse Sequences Related to Figures

Figure 3. Images of a deep neural-over-mesoderm explant show F-spondin expression.

(2.1 Mb timelapse)

 

Figure 4. Images of a deep neural-over-mesoderm explant show Shh expression (top), fluorescent cells videorecorded from stages 13 to 13.5 (middle), and an overlay of the two (bottom).

 (2.3 Mb timelapse)

 

Figure 5. Images of a deep neural-over-mesoderm explant at stage 13 (A) show Shh expression (top), fluorescently-labeled cells within the medial domain (middle), and an overlay of the two (bottom).

(1.9 Mb timelapse)

 

Figure 7. In a deep neural-over-mesoderm explant videorecorded from stage 11.5 to stage 15, cell intercalation develops in an anterior-to-posterior and lateral-to-medial progression and is conservative (A).

(4.9 Mb timelapse)

 

Figure 8. In a deep neural explant videorecorded from stage 11.5 to stage 15, mediolateral cell intercalation is promiscuous (A).

(6.2 Mb timelapse)

 

Figure 11. In deep neural-over-mesoderm explants, notoplate boundaries and cell behaviors differentiate in a discontinuous anterior-to-posterior progression.

(part 1. 4.0 Mb timelapse; part 2 4.0 Mb timelapse; part 3 3.7 Mb timelapse)