Figure 5

Micromere contributions to the prototroch in Capitella teleta. (A) Diagram drawn from a confocal slice through a stage 5 larva showing five prototrochal cells. At this stage, each of the main rows of prototochal cells (m1, m2, m3) meets apically to form the densely ciliated region of the prototroch. The nuclei (black circles) are positioned apically for all five prototrochal cells. (B) Cropped z-stack of merged (left image) or single-channel (channel indicated in the top left corner of each image), confocal images through the prototroch of a late stage 6 larva after injecting 1c¹ with DiI. The images are a reflected right lateral view. The channels in the merged image are DiI (red), phalloidin (green) and TO-PRO-3 (blue). The image to the far-right is a close-up view of the single-channel phalloidin image. Each row of the prototroch is indicated with a horizontal line. (C, D) Anterior and left lateral diagrams of a late stage 6 larva showing micromere contributions to the five rows of prototrochal cells. Descendants of each micromere are indicated by specific colors, which are shown below the diagrams (light red = 1a¹, light blue = 1b¹, light orange = 1c¹, light green = 1d¹, red = 1a², blue = 1b², orange = 1c², green = 1d², light grey = 2a, brown = 2b, dark grey = 2c). The orientation of the diagrams or confocal images is indicated with arrows. A = anterior, aT = accessory prototroch, D = dorsal, L = left, m = main prototroch, P = posterior, phall = phalloidin, pT = posterior accessory prototroch, R = right, V = ventral.