Earlier, the proteasome was shown to be resistant to some non-ionic detergents, such as Triton X-100. However, other proteins, especially those which were derived from the most stable aggregates resistant to such a strong detergent as SDS, e.g. Gas1, Ape1 and Ape4, may represent proteins of DMP 543 constitutive amyloids. Of course, in all cases, a set of additional experimental assays is necessary to verify whether a new protein candidate identified by PSIA is indeed amyloidogenic or behaves like a prion. The developed approach also allowed us to extend the work on characterization of the ability of amyloids to induce polymerization of endogenous yeast proteins. Earlier it was demonstrated that polymers of proteins with extended polyQ domains, including mutant human huntingtin, caused appearance of SDSinsoluble aggregates of some chromosomally-encoded Q/N-rich proteins,,. Here, we show that amyloids of mutant human DAU 5884 hydrochloride huntingtin induce appearance of SDS-insoluble aggregates of at least six host proteins, Def1, Pub1, Rpn10, Bmh2, Sgt2, and Sup35. Notably, with one exception, all these proteins contain Q- or Q/N-rich tracts of different lengths supporting our suggestion that such proteins can interdependently form amyloids. It may however seem surprising that among the multitude of yeast Q/N-enriched proteins only these formed detectable aggregates in response to appearance of amyloids of mutant huntingtin. It is clear that the capability of a protein to aggregate should depend on its expression level, however with the exception of Sup35, identified proteins are only modestly expressed. Nevertheless, proteins enriched with Q and N may differ from each other by their intrinsic propensity to polymerize and the detected proteins may be among those which are most prone to polymerization. Except for Sup35, whose polymerization substantially contributes to toxicity of mutant huntingtin in yeast, other identified proteins are non-essential and therefore their polymerization-mediated inactivation modulates rather than causes a cytotoxic effect. In support of this, deletion of the DEF1 gene alleviated huntingtin toxicity in yeast, while Def1 was shown to colocalize with huntingtin aggregates. Sgt2 was also detected in huntingtin inclusions and has been proposed to be an amyloid sensor. Rpn10 and Bmh2 have not been previously shown to interact with huntingtin polymers, however Bmh1, which is highly similar to Bmh2, has been detected in huntingtin aggregates and shown to play a role in huntingtin toxicity via aggresome formation.