Term
| What is the microtubule organizing center of the cell called? |
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Definition
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Term
| What subunits are microtubules made of? |
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Definition
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Term
| What are the protofilaments in microtubules composed of? |
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Definition
| alpha and beta tubulin (beta points toward plus end) |
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Term
| Which end of the microtubule is associated with being anchored in the MTOC? |
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Definition
| - end, + end grows outward toward outer part of cell (important because kinesin moves toward the + so it can carry signals to the periphery of a cell) |
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Term
| What are taxols and what purpose do they serve? Why are they dangerous? |
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Definition
| taxols are compounds that hyper-stabilize the microtubules of the mitotic spinde, causing blockage of cell division and apoptosis. They are powerful anti-tumor drugs, but lack target specificity and can cause damage to non-cancer cells |
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Term
| What was meant by the "dynamic instability" of microtubules? |
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Definition
| There is a constant varying in the length of microtubules, synthesis of additional subunits is always occurring in conjunction with disassembly of the + end (initiated by hydrolysis of GTP at the + end) |
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Term
| Describe the search and capture model for microtubule stabilization |
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Definition
| Capping proteins on the cell membrane allow microtubules to bind to them as they extent out from the MTOC. This process can cause cellular projections and alterations of cell poles |
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Term
| What are MAPS and how do they function? |
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Definition
| They stabilize microtubules permitting additional assembly by binding to the outside of the microtubule |
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Term
| What are the two motor proteins associated with movement along microtubules and what direction does each travel toward? |
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Definition
1. Kinesin - moves toward + end
2. Dyneins - moves toward - end |
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