Role and regulation of the ER chaperone BiP.
BiP, an HSP70 molecular chaperone located in the lumen of the endoplasmic reticulum (ER), binds newly-synthesized proteins as they are translocated into the ER and maintains them in a state competent for subsequent folding and oligomerization. BiP is also an essential component of the translocation machinery, as well as playing a role in retrograde transport across the ER membrane of aberrant proteins destined for degradation by the proteasome. BiP is an abundant protein under all growth conditions, but its synthesis is markedly induced under conditions that lead to the accumulation of unfolded polypeptides in the ER. This attribute provides a marker for disease states that result from misfolding of secretory and transmembrane proteins.
Gething
M J
MJ
Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.
D015415:Biomarkers / Q000032:analysis; D004721:Endoplasmic Reticulum / Q000737:chemistry*; D005656:Fungal Proteins / Q000032:analysis / Q000378:metabolism; D005786:Gene Expression Regulation; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D006360:Heat-Shock Proteins / Q000378:metabolism; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry
D015415:Biomarkers; D005656:Fungal Proteins; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C060153:KAR2 protein, yeast; D010455:Peptides