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.

An HRD/DER-independent ER quality control mechanism involves Rsp5p-dependent ubiquitination and ER-Golgi transport.

http://www.ncbi.nlm.nih.gov/pubmed/12105183

We have identified a new pathway of ER-associated degradation in Saccharomyces cerevisiae that functions separately from the HRD/DER pathway comprised of Hrd1p, Hrd3p, Der1p, and Ubc7p. This pathway, termed Hrd1p independent-proteolysis (HIP), is capable of recognizing and degrading both lumenal (CPY* and PrA*), and integral membrane proteins (Sec61-2p) that misfold in the ER. CPY* overexpression likely saturates the HRD/DER pathway and activates the HIP pathway, so the slowed degradation kinetics of CPY* in a hrd1 Delta strain is restored to a wild-type rate when CPY* is overexpressed. Substrates of HIP require vesicular trafficking between the ER and Golgi apparatus before degradation by the ubiquitin-proteasome system. Ubiquitination of HIP substrates does not involve the HRD/DER pathway ubiquitin ligase Hrd1p, but instead uses another ubiquitin ligase, Rsp5p. HIP is regulated by the unfolded protein response as Ire1p is necessary for the degradation of CPY* when overexpressed, but not when CPY* is expressed at normal levels. Both the HIP and HRD/DER pathways contribute to the degradation of CPY*, and only by eliminating both is CPY* degradation completely blocked.

Pubmed ID: 12105183 RIS Download

Mesh terms: Cytosol | Dose-Response Relationship, Drug | Endoplasmic Reticulum | Endosomal Sorting Complexes Required for Transport | Fungal Proteins | Golgi Apparatus | Kinetics | Ligases | Membrane Glycoproteins | Membrane Proteins | Models, Biological | Precipitin Tests | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Time Factors | Ubiquitin | Ubiquitin-Conjugating Enzymes | Ubiquitin-Protein Ligase Complexes | Ubiquitin-Protein Ligases

Research resources used in this publication

None found

Research tools detected in this publication

None found

Data used in this publication

None found

Associated grants

  • Agency: NIGMS NIH HHS, Id: GM55848

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.