A multi-well version of in situ hybridization on whole mount embryos of Caenorhabditis elegans.

We report an efficient procedure for in situ hybridization with a multi-well format on Caenorhabditis elegans embryos for large scale screening of gene expression patterns in this organism. Each hybridization well contains embryos at various stages throughout embryogenesis. The validity of the method was confirmed through results with control genes whose expression patterns have been reported; glp-1 in very early embryos, myo-2 in pharyngeal muscle and unc-54 in body wall muscle. Several collagen genes and a pepsinogen gene were also examined to establish a set of lineage-specific markers. As a pilot project, we examined approximately 100 unique cDNA species classified by our cDNA project, finding that approximately 10% of the cDNA groups were expressed in specific cells and at specific stages.