intermediate filaments Flashcards
what is the key function of IFs
providing structural integrity to cells and tissues
what are the 5 classes of IFs
keratins (basic and acidic), lamins, neurofilaments, desmin
where would you find desmin
in muscles
where would you find keratins
in epithelia
where would you find lamins
in the nucleus
describe the structure of a IF dimer
head and tail held together by coiled-coil rod domain
what happens when 2 dimers associate
they bind to form an antiparallel tetramer
how is a protofilament formed
many tetramers are associated end to end into a long line that is a protofilament
how many protofilaments form a protofibril
4
how many protofibrils form a IF
4
why aren’t IFs used by motor proteins as a track
they have no polarity or associated nucleotides (ATP / GTP)
no directional information to motor proteins
why don’t IFs have polarity
they are symmetrical so have indistinguishable ends
example of a keratin mutation
k14 keratin mutations lead to blistering of the skin
