Endoplasmic reticulum chaperones

Chaperones. Figure 2 The multiple roles of BiP in the biogenesis of the secretory proteins. BiP, immunoglobulin heavy chain binding protein ER, endoplasmic reticulum ERAD, ER-associated degradation ERj, resident ER protein with J-domain Sec61, core subunit of the protein translocase UPR, unfolded protein response that involves several signal transduction pathways that are activated in order to increase the biosynthetic capacity and decrease the biosynthetic burden of the ER... 

Table 46-6. Some chaperones and enzymes involved in folding that are located in the rough endoplasmic reticulum.

Wearsch PA, Voglino L, Nicchitta CV (1998) Structural transitions accompanying the activation of peptide binding to the endoplasmic reticulum Hsp90 chaperone GRP94. Biochemistry 37(16) 5709-5719... 

Comparison of two analytical approaches, atomic force microscopy (AFM) and quartz crystal microbalance, for studying the binding of Con A to glycosylated carboxypeptidase, demonstrated that both could determine the quantitative parameters characterizing the interaction.65 Quantitative analyses of the interaction of Calreticulin (CRT), which is a soluble molecular chaperone of the endoplasmic reticulum, with various... 

Frohlich, K U., Diamant, N., and Bar-Nun, S. AAA-ATPase p97/ Cdc48p, a cytosolic chaperone required for endoplasmic reticulum-assodated protein degradation. Mol Cell Biol 2002, 22, 626-34. 

Brodsky JL, Werner ED, Dubas ME, Goeckeler JL, Kruse KB, McCracken AA (1999) The requirement for molecular chaperones during endoplasmic reticulum-assodated protein degradation demonstrates that protein export and import are mechanistically distinct. J Biol Chem 274 3453-3460 Brown CR, Doxsey SJ, White E, Welch W (1994) Both viral (adenovirus ElB) and cellular (hsp 70, p53) components interact with centrosomes. J Cell Physiol 160 47-60... 

Knittler MR, Dirks S, Haas IG (1995) Molecular chaperones involved in protein degradation in the endoplasmic reticulum quantitative interaction of the heat shock cognate protein BiP with partially folded immunoglobulin light chains that are degraded in the endoplasmic reticulum. Proc Natl Acad Sd USA 92 1764-1768... 

They may enter the cytosol and fold quickly into a compact form. This may require only a few seconds, whereas the translation process in the ribosome may take many seconds. The folding will therefore be cotranslational.525 Depending upon the N-terminal signal peptide the protein may later unfold and pass through a membrane pore or translocon into the endoplasmic reticulum (ER), a mitochondrion, chloro-plast, or peroxisome. Wherever it is, it will be crowded together with thousands of other proteins. It will interact with many of these, and evolution will have enabled some of these to become chaperones (discussed in Chapter 10).526... 

Michalak, M., Robert Parker, J. M., and Opas, M., 2002, Ca2+ signaling and calcium binding chaperones of the endoplasmic reticulum. Cell Calcium, 32 269-78. 

Nagata K. Expression and function of heat shock protein 47 a collagen-specific molecular chaperone in the endoplasmic reticulum. Matrix Biology 1998, 16, 379-386. 

Randow, F., Seed, B. Endoplasmic reticulum chaperone gp96 is required for innate immunity but not cell viability. Nat Cell Biol 3 (2001) 891-896. 

Punt PJ, van Gemeren IA, Drint-Kuijvenhoven J et al (1998) Analysis of the role of the gene bipA, encoding the major endoplasmic reticulum chaperone protein in the secretion of homologous and heterologous proteins in black Aspergilli. Appl Microbiol Biotechnol 50 447 154... 

To understand how structural defects in collagen could cause OI, we need to follow the collagen fiber synthesis pathway (Fig. 3-3). It starts from synthesis of precursor (procollagen) chains. Association of two pro-al(I)- and one pro-a2(I)-chains at their C-propeptides initiates procollagen folding, which proceeds in a zipperlike manner from C- to N-terminal end of the molecule (Engel and Prockop, 1991).These processes occur inside the endoplasmic reticulum (ER) and are assisted by a variety of ER chaperones and enzymes (Lamande and Bateman, 1999). 

Lamande SR, Bateman JF Procollagen folding and assembly the role of endoplasmic reticulum enzymes and molecular chaperones. Semin Cell Dev Biol 10 455-464,1999. 

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