Term
Rabs can do the following:
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Definition
-They can bind Molecular Motors
-They can Assemble Docking Complexes
-They can Regulate SNARE Activity
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Term
Diseases Resulting from Defects in Vesicle Trafficking
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Definition
Hermansky-Pudlak syndrome involves a defect in an adaptor protein leading to mis-sorting of lysosomal enzymes. Patients are characterized by hypopigmentation (defective melanosomes), bleeding disorders (defective platelets),
Chediak-Higashi Syndrome is characterized by the presence of enlarged lysosomes and patients suffer from partial albinism, bleeding disorders, recurrent bacterial infections and other immune deficiencies.
Griscelli Syndrome is presents as the above diseases and involved defects in either a Rab protein or an actin molecular motor regulating transport of lysosomes.
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Term
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Definition
-moves things from plasma membrane and Tran-Golgi to endosomes |
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Term
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Definition
-moves vesicles between Golgi cisternae and from cis-Golgi to the ER
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Term
Adaptor proteins and small GTPases..... |
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Definition
are required for formation of coated vesicles.
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Term
There are at least three entry routes into cells |
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Definition
-Phagocytosis
-Receptor-mediated endocytosis (clathrin dependent)
-Pinocytosis (clathrin independent)
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Term
Macropinocytosis: What do we know?
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Definition
1. Constitutive process in Dendritic cells.
2. Induced in ras and src transformed fibroblasts.
3. Induced by phorbol esters, growth factors, fMLP and
Salmonella
Macropinocytosis plays a key role in antigen presentation, bacterial invasion and endocytic withdrawal of large membrane domains, but the process is only poorly characterized. Actin polymerization is important.
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Term
Mechanisms of Particle Internalization
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Definition
•Material can be bacteria, fungi and dying cells.
•Receptor mediated includes Fc receptors and complement mediated. Fc receptor mediated internalization requires the extension of a membrane pseudopod.
•Polymerization of F-actin is required and localized to forming phagosomal cup.
•The zipper hypothesis explains the movement of membrane around the particle.
•Pathogens can also trigger their own entry into cells or actively invade cells to gain admittance.
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Term
Receptor Mediated Endocytosis
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Definition
A specific receptor binds to an extracellular ligand.
The plasma membrane containing this receptor then undergoes internalization and selectively recruits the receptor and excludes other proteins.
Receptors may travel to lysosomes or be recycled back to the cell surface.
Receptors include: LDL, M6pR, ErbB1, transferrin as examples |
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Term
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Definition
-connect the receptor tail with clathrin. Three flavors: AP1, AP2 and AP3. |
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