14-3-3ζ structural features and deletion mutants used in yeast 2-hybrid cotransformations with platelet GPIb subunits. Known and putative domains include a 26-residue N-terminal dimerization domain (DD),8,9 a domain with homology to the C terminus of the annexin protein family that acts as a protein kinase C (PKC) inhibitor (AHD),10 and a putative C-terminal PKC-inhibitory domain that a recent mutagenesis investigation was unable to more precisely localize (PKC ID).8 A C-terminal phosphoserine (residue 185*) has also been characterized.11