Binding protein endoplasmic reticulum

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... 

The signal recognition particle (SRP) is a cytosolic ribonucleoprotein complex which binds to signal sequences of nascent membrane and secretory proteins emerging from ribosomes. The SRP consists of a 7S RNA and at least six polypeptide subunits (relative molecular masses 9, 14, 19, 54, 68, and 72 kD). It induces an elongation arrest until the nascent chain/ ribosome/SRP complex reaches the translocon at the endoplasmic reticulum (ER) membrane. 

Brodifacoum, difenacoum, flocoumafen, and other superwarfarins bind strongly to proteins of the hepatic endoplasmic reticulum and consequently have long half-lives in vertebrates, often exceeding 100 days. Thus, they present a hazard to predators and scavengers that feed on rodents which have been exposed to superwarfarins. A number of species of predatory and scavenging birds have died as a consequence... 

Walter, P., and Blobel, G. (1981b). Translocation of proteins across the endoplasmic reticulum. II. Signal recognition protein (SRP) mediates the selective binding to microsomal membranes of in cdro-assembled polysomes synthesizing secretory protein. J. Cell Biol. 91, 551-556. 

SADP or sulfo-SADP also have been used to study the phenylalanine-methionine-arginine-phenylalanine-amide-activated sodium channel (Coscoy et al., 1998), various apolipoprotein E isoforms (Mann et al., 1995), the high-affinity phenylalkylamine Ca2+ antagonist binding protein from guinea pig (Moebius et al., 1994), the interaction of non-histone proteins with nucleosome core particles (Reeves and Nissen, 1993), and the interactions among cytochromes P-450 in the endoplasmic reticulum (Alston et al., 1991). See Chapter 28 for methods of using photoreactive heterobifunctional crosslinkers to study protein interactions. 

Moebius, F.F., Hanner, M., Knaus, H.G., Weber, F., Striessnig, J., and Glossmann, H. (1994) Purification and amino-terminal sequencing of the high affinity phenylalkylamine Ca2+ antagonist binding protein from guinea pig liver endoplasmic reticulum./. Biol. Chem. 269, 29314-29320. 

Calumin Membrane-spanning calcium-binding protein involved in Ca2+-handling and signaling in the endoplasmic reticulum (368)... 

From overexpression studies, it can be inferred that individual isoforms of PKC are precisely directed to distinct subcellular locations (e.g. PKCa to the endoplasmic reticulum and PKCS to the Golgi). Directing PKC isozymes to specific subcellular loci appears to occur via interaction of the enzyme with localized intracellular binding proteins. Such proteins may or may not be substrates for PKC. An example of the latter category would be RACK (receptors for activated C kinase) 1. RACKs are thought to interact only with activated PKCs and to direct translocated PKCs to specific loci. 

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