Worm Breeder's Gazette 16(1): 46 (October 1, 1999)

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Dye-coupling in Wild-type C. elegans Neurons

Miriam B. Goodman1, Shawn R. Lockery2, Marty Chalfie1

1 Dept Biological Sciences, Columbia University, New York, NY 10027
2 Inst. of Neuroscience, University of Oregon, Eugene, OR 97403-1254

Small, fluorescent dyes permeate gap junctions between neurons in both vertebrates and invertebrates. While not all gap junctions are dye-permeable, dyes are useful tools for determining the extent of coupling among neurons. We have tested the ability of 3 low molecular weight dyes to permeate gap junctions between neurons in worms. We focused on dyes that could be visualized simultaneously with GFP (Table I). All 3 dyes labeled multiple cell bodies when introduced via a patch pipette into a single cell body, indicating that these dyes could permeate neuronal gap junctions. To date, the largest group of dye-coupled cell bodies had only 3 labeled cells. This observation suggests that functional coupling may be restricted to first-order partners, despite an extensive network of gap junctions between neurons.

Table I

Dye (MW, net charge)

Labeled Cells (n)*

Cascade Blue (645g, -2)

1.25 (4)

Lucifer Yellow (522g, -3)

1.5 (2)

sulforhodamine 101(607g, 0)

1.3 (11)

*n = number of dye-injected cells