s of Oral Program 43 Abstracts of Poster Program 213s of Poster Program 213 Speaker/Presenter Index 279 List of Preregistered Conferees 283 Meetings of Interest 315

The third extracellular loop of the human delta-opioid receptor (hDOR) is known to play an important role in the binding of delta-selective ligands. In particular, mutation of three amino acids (Trp(284), Val(296), and Val(297)) to alanine significantly diminished delta-opioid receptor affinity for delta-selective ligands. To assess the changes in conformation accompanying binding of the endoge...

Prior studies identified a segment of the CD2 cytoplasmic domain between amino acid (aa) residues 253 and 287 as important in T lymphocyte signal transduction. This region contains two repeats of the sequence motif PPPGHR, thought to form a "cage" structure involved in CD2-mediated signaling. To evaluate this segment, a series of mutant human CD2 molecules were produced by oligonucleotide-direc...