Exploring the functional complexity of cellular proteins by protein knockout Academic Article uri icon


MeSH Major

  • Proteins


  • Comprehensive dissection of protein functions entails more complicated manipulations than simply eliminating the protein of interest. Established knockdown technologies, such as RNA interference, antisense oligodeoxynucleotides, or ribozymes, are limited for specific applications such as modulating protein levels or specific targeting of a posttranslationally modified subpopulation. Here we show that the engineered Skp1, Cullin 1, and F-box-containing betaTrCP substrate receptor ubiquitin-proteolytic system, designated protein knockout, could achieve not only total elimination but also rapid and systematic reduction of a given cellular protein. Stable expression of a single engineered betaTrCP demonstrated simultaneous and sustained degradation of the entire retinoblastoma family proteins. Furthermore, the engineered betaTrCP was capable of selecting hypo- but not hyperphosphorylated forms of retinoblastoma for degradation. The engineered betaTrCP has been extensively modified to increase its specificity in substrate selection. This optimized protein-knockout system offers a powerful and versatile proteomic tool to dissect diverse functional properties of cellular proteins in somatic cells.

publication date

  • November 25, 2003



  • Academic Article



  • eng

PubMed Central ID

  • PMC283557

Digital Object Identifier (DOI)

  • 10.1073/pnas.2233012100

PubMed ID

  • 14593203

Additional Document Info

start page

  • 14127

end page

  • 32


  • 100


  • SUPPL. 2