Contractile Proteins Flashcards
What is contractile ring made of ?
actin and myosin 2
What is the basic organization of actin parallel arrays?
actin fibers crosslinked together
Function of myosin V?
organelle and vesicle transport
What is filamin and its function?
acting binding protein, creates 3D meshwork by binding actin
What is the organization name for actin networks in 3D meshwork ?
orthogonal arrays
Funciton of Myosin VI?
move vesicles to negative end of actin
What -podia associated with phagocytosis?
pseudopodia
Erythrocytes contain spectrin.
What do they do?
forms actin network that makes up cortical cytoskeleton
Where would you see an actin contractile bundle?
in muscles for contraction
in contractile ring for mitosis
What is the only myosin that moves to negative end of actin?
Myosin VI
Which myosin associated with skeletal muscle?
Myosin 2
What fiber is important for all the -podias?
Actin
What determines the association of actin filaments?
size and shape of actin binding proteins
What is DMD?
mutation in dystrophin gene resulting in muscle wasting (X linked)
What will myosin with LONGer neck have over myosin with shorter neck?
higher velocity powerstroke ( this is referring to length of LIGHT CHAIN NECK PORTION not the tail of the myosin)
Where do you see ATPase activity in Myosin?
head
What might be deficient in Hereditary Spherocytosis?
ankyrin, spectin, protein 4.1
What facilitates cross linking of actin bundles
actin bundling proteins
Where would you find myosin light chain peptides?
neck region of myosin
What contributes to prevention of myosin binding to actin in smooth muscle? What enzyme causes this inhibitory state?
folding of myosin by regulatory light chain in the neck
myosin light chain kinase
Function of MYosin 1?
assists with endocytosis
What causes a myosin power stroke?
release of Pi
What does dystrophen gene do?
connects cytoskeleton to basal lamina, stabilizes membrane
What enzyme in smooth muscle activates myosin ?
myosin light chain kinase
