Preparing your results

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Modularity of the Hrd1 ERAD complex underlies its diverse client range.

http://www.ncbi.nlm.nih.gov/pubmed/20212318

Secretory protein folding is monitored by endoplasmic reticulum (ER) quality control mechanisms. Misfolded proteins are retained and targeted to ER-associated degradation (ERAD) pathways. At their core are E3 ubiquitin ligases, which organize factors that recognize, ubiquitinate, and translocate substrates. Of these, we report that the Hrd1 complex manages three distinct substrate classes. A core complex is required for all classes and is sufficient for some membrane proteins. The accessory factors Usa1p and Der1p adapt the complex to process luminal substrates. Their integration is sufficient to process molecules bearing glycan-independent degradation signals. The presence of Yos9p extends the substrate range by mediating the recognition of glycan-based degradation signals. This modular organization enables the Hrd1 complex to recognize topologically diverse substrates. The Hrd1 system does not directly evaluate the folding state of polypeptides. Instead, it does so indirectly, by recognizing specific embedded signals displayed upon misfolding.

Pubmed ID: 20212318 RIS Download

Mesh terms: Animals | Carrier Proteins | Endoplasmic Reticulum | Membrane Proteins | Molecular Chaperones | Polysaccharides | Protein Folding | Protein Sorting Signals | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Substrate Specificity | Ubiquitin-Protein Ligases