Display Settings:

Format

Send to:

Choose Destination
    Nature. 2002 Jul 25;418(6896):438-42.

    E3 ubiquitin ligase that recognizes sugar chains.

    Source

    Department of Tumor Immunology, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613, Japan.

    Abstract

    N-glycosylation of proteins in the endoplasmic reticulum (ER) has a central role in protein quality control. Here we report that N-glycan serves as a signal for degradation by the Skp1-Cullin1-Fbx2-Roc1 (SCF(Fbx2)) ubiquitin ligase complex. The F-box protein Fbx2 (ref. 4) binds specifically to proteins attached to N-linked high-mannose oligosaccharides and subsequently contributes to ubiquitination of N-glycosylated proteins. Pre-integrin beta 1 is a target of Fbx2; these two proteins interact in the cytosol after inhibition of the proteasome. In addition, expression of the mutant Fbx2 Delta F, which lacks the F-box domain that is essential for forming the SCF complex, appreciably blocks degradation of typical substrates of the ER-associated degradation pathway. Our results indicate that SCF(Fbx2) ubiquitinates N-glycosylated proteins that are translocated from the ER to the cytosol by the quality control mechanism.

    PMID:
    12140560
    [PubMed - indexed for MEDLINE]

      Supplemental Content

      Icon for Nature Publishing Group

      Save items

      loading

      Recent activity

      Your browsing activity is empty.

      Activity recording is turned off.

      Turn recording back on

      See more...
      Write to the Help Desk