

I discovered the C-cell in embryonic leeches as a postdoc in W.B Kristan's lab. I was examining peripheral neurons and muscles and encountered this very novel cell in the body wall of the leech embryo. I originally called it the "centipede cell" based on its very early appearance but an editor rejected the notion that a cell in the leech would be named after an arthropod, so, "comb cell" seemed just as descriptive. I continued these studies with students (especially Diane Kopp) in my own lab over the next few years.
We studied this cell with two distinct foci. First, it's fantastic morphology made it a wonderful model to ask how growth cones navigate. Second, I discovered that this cell served a unique role in development - it provided a scaffold for the assembly of an entire muscle layer!
Every segment has a bilateral, mirror-image pair of C-cells. Each C-cell projects a front of 35 growth cones medially and laterally to establish a grid of parallel processes. These gowth cones navigate at a 45 degree angle to the long axis and as each spirals around toward the dorsal midline, contralateral homogs cross each other.




We discovered that the C-cell resided in the body wall, sandwiched between the superficial circular muscle and the deeper longitudinal muscle. The processes are added at either end and expand to fill, or tile the area. This tiling is something many neurons do, for example amacrine cells in the vertebrate retina. For a brief peek at a few things we learned about this cell, click the image of the young C-cell at the left.