Confocal analysis of strains containing the Punc-31::GFP transcriptional reporter revealed expression in the nerve ring, ventral nerve cord motor neurons, preanal ganglion, and head ganglion. Counts of cell bodies in the ventral nerve cord and preanal ganglion revealed an average of 65 +/- 2 (n = 4) GFP-positive cells, indicating that essentially all of the neurons of the ventral nerve cord and preanal ganglion express
unc-31. Additional positive identifications were made for SDQ, PDE, BDU, ALM, DVA, DVB, DVC, HSN, and CAN neurons. Because these encompass most of the identifiable neurons in the background of a pan-neuronal expression pattern, authors infer that
unc-31 may be expressed in essentially all neurons. All reporter strains also displayed expression in the vulval muscles VM1 and VM2 and occasional expression in what is likely VulE and VulF. Consistent expression was also noted in the UV1 cells and the spermatheca. In summary, CAPS/UNC-31 is expressed throughout the nervous system and in other secretory cells.