gOlgi

Apuntes

Class of the GOLGI APPARATUS Prof. Lilian Spencer The last class you saw this figure. Please, Explain. Only correctly folded proteins are transported from RER to the Golgi. Response to inadequate folding in ER ↓ IRE1 (Protein transmembrane of the nuclear membrane) ↓ Active of Transcription Factor HAC1 ↓ Activates transcription of chaperone genes (E.g.Hsp70 ) Fig. Non-folded protein response. (UPR, Unfolded-protein response) Scheme of the protein secretion pathway Secretion Proteins + Carbohydrate Chains → Glycosylation → R-ER Golgi ́s cisternae Protein folding is permanently attached to the Hsc70 and Calnexin chaperones of the RER Protein IRE-1 Nuclear transmembrane + Bad folded protein ↓ Transcription factor activation HAC1 ↓ Synthesis of chaperones ↓ Assistance in folding processes Ubiquitin-mediated proteolytic pathway. • Degradation of non-folded proteins in the ER are transported to the cytosol through the translocon → Ubiquitynization → Proteasome → Degrade * Note: It is not known, how bad folded proteins are recognized and directed to the translocon to be ubiquytinated in the cytosol. Poly-ubiquitinization Lysine The major routes for prote...