Polylysine interactome in human cells

Polylysine chains are synthesized by ribosomes when a stop codon preceding the polyA tail on the mRNA fails to terminate the translation. To clarify the faith of the polylysine-tagged chains, we analyzed polylysine interactome in the cytosol of human 293T cells. We found an extensive network of interactors involving key complexes of protein quality control, such as TRiC and 26S proteasome. The presence of components of the nuclear transport machinery among polylysine interactors and an enhanced nuclear import suggest a mechanism for compartmentalization of faulty proteins in the cell.