Joint 1 - The Cytoskeleton Flashcards
role of microtubules?
- cell shape
- mitotic spindle
- cilia
- movement tracking
monomer of microtubules?
- tubulin
- a and b sub unit form a dimer
- GTP on b sub unit gets hydrolysed
how is a protofilament formed?
- many tubulin dimers form bonds linear
- plus end at top
- minus at bottom
- dimers attach to + end
how can a microtubule be elongated or shortened?
- elongation - by polyermerisation of more dimers
- shorten - depolyermerisation of dimers
thermostability of microtubules?
- dynamically unstable
two types of microtubule binding drugs?
Tubulin dimer binding
- stop polyermerisation
- drug inhibits poly
Tubulin polymer binding
- binds to a formed MT to make it unable to be deploy such as taxol
- increase poly
what are MAPS?
microtubule associating proteins
- can speed up poly
- associate with the MT which can then attach to vesicles and other MTs
Roles of actin microfilaments?
cell shape
cell movement
movement trackment of vesicles
monomers of microfilament?
actin (monomeric)
binds to ATP {when in filament its bound to ADP]
how do microfilaments form?
actin monomers attach (+ end at the top)
examples of drugs that affect actin?
phallodin
- lock actin filaments that are adjacent together to prevent polymerisation
cytochalsalin
-bind to actin filament prev poly
what are ABP?
actin binding proteins
regulate actin poly
what are intermediate fillaments made of?
- not one monomer
- made of many proteins
how is a intermediate filament made?
- 2 tetramers bind to form a coiled coil dimer
- many associate together
