Intracellular Trafficking How proteins know where to go
Nucleus Nuclear import & Export
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Mitochondria Import to the Mitochondrial Matrix & Intramembranous Space
- - - - - - - - + + + + + + + + - - - - - - - -
Endoplasmic Reticulum Sorting to the ER lumen & Insertion in the ER membrane
hydropathy plot H2N COOH
NH2 COOH H2N COOH NH2 COOH
hydropathy plot H2N COOH
Endoplasmic Reticulum Modification at the ER and Folding of Soluble Proteins
“Post-translational modifications” = co-translational glycosylation addition of lipids protein folding (removal of signal peptide)
“consensus sequence” = Asn-X-Ser/Thr N-linked glycosylation “consensus sequence” = Asn-X-Ser/Thr
Protein Folding
ER “Retention” KDEL = Lys-Asp-Glu-Leu-C term
Vesicular Transport Secretory Pathway
“constitutive secretory pathway”
COP = Coatomer Protein
Endocytosis Exocytosis
Figure 13-13b Molecular Biology of the Cell (© Garland Science 2008)
Sar 1 hydrolyzes GTP GDP Sar 1 is no longer in the vesicle membrane Sec proteins no longer coat the vesicle (i.e., coat disassembles) Figure 13-13d Molecular Biology of the Cell (© Garland Science 2008)
Rab Proteins SNARE Proteins
Figure 13-16 Molecular Biology of the Cell (© Garland Science 2008)
Figure 13-17 Molecular Biology of the Cell (© Garland Science 2008)
Page 779 Molecular Biology of the Cell (© Garland Science 2008)
Figure 13-43 Molecular Biology of the Cell (© Garland Science 2008) P
lysosome pH decrease Figure 13-44 Molecular Biology of the Cell (© Garland Science 2008)