Term
| How do molecules move through the Golgi? |
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Definition
There was and continues to be a question/argument as to how molecules move through the GOLGI
Are Vesicles used that bud from one compartment and fuse to the next?
Or, does a GOLGI compartment mature into the next compartment (cis GOLGI matures into medial GOLGI, medial into trans GOLGI etc…)? |
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Term
| Pretreat cells with nocodazole - |
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Definition
disassembles microtubules
Incubate at 40˚C
Shift to 32˚C
Peripheral pre-GOLGI structures |
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Term
| Transport through the Golgi |
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Definition
| ER--> ERGIC --> CIS --> Trans |
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Term
| What evidence for vesicular transport? |
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Definition
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Term
| Evidence for cisternal maturation 1-3 |
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Definition
1. Vesticles move from ER to golgi 2. vesticles coalesce to form new cis Golgi cisternae
3. Cisternal Maturation: Golgi cisternae moves in a cis to trans direction. |
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Term
| Evidence for cisternal maturation 4-6 |
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Definition
| 4. Vesicles form and leave golgi, carrying specific proteins to other locations or to the pm for secretion. 5. Vesicles transport specific proteins backwards to newer golgi cisternae. 6. Vesicles also transport certain proteins back to the ER |
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Term
| Different type of cells, different movements. |
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Definition
| Non-polarized- don't have different 'sides' Polarized- have different 'sides' |
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Term
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Definition
| Not all membranes are the same, some are specialized. Seperated by a protein complex called a tight junction. |
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Term
| Nerve cells are also polarized… |
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Definition
Axonal membrane similar to apical membrane
Cell body membrane similar to basolateral membrane |
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Term
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Definition
enriched in glycosphingolipids
glycosylphosphatidylinositol (GPI) anchored proteins made in GOLGI - when transported to plasma membrane, found exclusively in apical membrane
Question - how do these proteins (and lipid rafts) get to PM? |
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Term
Packaging into vesticles
Apical sorting signals - |
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Definition
...GPI-anchored proteins and lipid rafts (apical/axonal)
not sure what the signals are |
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Term
Packaging into vesticles
Basolateral sorting signals |
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Definition
tyrosine motif (a sequence of amino acids that has a particular set of tyrosines Y)
Di-leucine motifs (xxxxxxLLxxxxxxx) |
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Term
Transport from the trans-golgi
Not all Proteins go to the...
Sorting occurs in the... |
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Definition
... plasma membrane
... trans-GOLGI
Different signals go to different places |
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Term
Tranport from the trans-golgi
Transport to lysosomes...
Transport to regulated ...
Transport on ______ pathway |
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Definition
... via endosomes
...secretory vesicles (required when cells need to rapidly respond to a stimulus)
-constitutive |
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Term
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Definition
| Constitutive - happening all the time and responsible for taking membrane proteins and soluble proteins destined for secretion to the plasma membrane |
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Term
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Definition
Regulated exocytosis - occurs in specialized cells
Hormones
Neurotransmitters
Digestive enzymes |
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Term
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Definition
Best examples
Mast cells
Neuronal cells
Beta-cells of pancreas! |
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Term
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Definition
Signals that regulate when exocytosis occurs
Binding of ligand to receptor
Causes signals of some sort…
Calcium fluxes in neuronal cells, results in release of neurotransmitters |
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Term
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Definition
| Pancreatic beta cells - release insulin in response to glucose |
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Term
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Definition
Immune cells responsible for allergic response
Allergens bind to receptors on cell surface
Causes the release of histamine |
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Term
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Definition
Why is a localized response important?
Cytotoxic T-cell |
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Term
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Definition
1-3
1. Delivery of synaptic vesticles components to plasma membrane
2. Endocytosis of synaptic vesticles components to form new synaptic vesticles directly
3. Endocytosis of synaptic vesticle components and delivery to endosome. |
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Term
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Definition
4. Budding of synaptic vesticles from endosome.
5. Loading of neurotransmitters into synaptic vesticles
6. Secretion of neurotransmitters by exocytosis on response to an action potential. |
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Term
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Definition
Bind to nerve terminal and are ready for release upon proper stimulus
Action potential results in calcium influx - signals the release |
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