A modulator of regulatory cellular events occurring intracellularly which are mediated by regulatory proteins containing a ‘death domain’ motif is provided. The ‘death domain’ is a regulatory portion of the regulatory proteins, and the modulator is capable of interacting with one or more ‘death domain’ motifs contained in the regulatory proteins and affecting the regulatory action of one or more of the regulatory proteins. The modulator preferably is capable of interacting with ‘death domain’ motifs within p55-TNF-R, FAS/APO1-R, NGF-R, MORT-1, RIP, TRADD, or ankyrin. A method for producing the modulators is also provided. The modulators are useful for modulating functions mediated in cells by proteins containing the ‘death domain’.